|
Search of All Forums Enter your search criteria. Click here for tips on using our search |
For Sale Ads |
1: Tube DIY Asylum, RE: One more question for the experts ... impedance (0.00)
Posted by PeterI on 2022-07-27, 08:36:03 (72.105.71.92)
Yeah, already removed the. 0.1uf input cap and extra 15Kohm resistor. Just a 15Kohm R to the grid. Cheers -P .......
2: Tube DIY Asylum, One more question for the experts ... impedance (0.00)
Posted by PeterI on 2022-07-26, 15:47:52 (72.105.71.92)
Thanks for the info and advice below. One thing: my Audible Illusions L1 tube preamp suggests using with power amplifier with input impedance of 50Kohms but best with no more than 400K ohms. My Hk w5 .......
3: Tube DIY Asylum, Most of those things completed. NT (0.00)
Posted by PeterI on 2022-07-26, 15:24:38 (72.105.71.92)
nt .......
4: Tube DIY Asylum, RE: 6L6GC screens in Heathkit W5m amps. (0.00)
Posted by PeterI on 2022-07-26, 15:17:21 (72.105.71.92)
Thanks Mr. McShane. Per the original schematic I have 270ohm 1W screen Rs. I first put in 470 ohm but the voltage to screens is same anyway. I put CL-80 3A surge limiter in the AC line, thinking it wa .......
5: Tube DIY Asylum, RE: 6L6GC screens in Heathkit W5m amps. (0.00)
Posted by PeterI on 2022-07-26, 15:06:56 (72.105.71.92)
Thanks for info. That totally makes sense since those tubes are what was supplied OEM by Heath. My incomplete info on KT66s comes from TDSL. -P .......
6: Tube DIY Asylum, RE: Beautiful work! (0.00)
Posted by PeterI on 2022-07-26, 15:02:47 (72.105.71.92)
Thanks. That is a dual AC to DC regulated filament supply. Supplied 12.4VDC to 12BY7 input tubes and 6.2VDC to 6CG7 tubes. -Pete Outside view: .......
7: Tube DIY Asylum, RE: 6L6GC screens in Heathkit W5m. Citation V (0.00)
Posted by PeterI on 2022-07-24, 14:49:46 (72.107.219.204)
That Citation will be great. I never had one but I built a sort-of clone based on the circuit. The picture is that amp. May not bear any relationship visually to a real Cit V but it sounded great. P .......
8: Tube DIY Asylum, Thanks. NT (0.00)
Posted by PeterI on 2022-07-24, 07:34:03 (72.107.219.204)
nt .......
9: Tube DIY Asylum, Great, thank you. (0.00)
Posted by PeterI on 2022-07-23, 18:07:05 (72.107.219.204)
The amps have mostly new resistors and capacitors. A case of "While I'm in there..." Power supplies crucial as start-up surges are high, despite a CL-80 limiter and 5R4 rectifier. Thanks -P ::: TOPIC .......
10: Tube DIY Asylum, RE: 6L6GC screens in Heathkit W5m amps. (0.00)
Posted by PeterI on 2022-07-23, 16:52:35 (72.107.219.204)
How does this help, Tim? I've been getting useful friendly advice from this forum for over 12 years. And grateful for it. .......
11: Tube DIY Asylum, 6L6GC screens in Heathkit W5m amps. (0.00)
Posted by PeterI on 2022-07-23, 14:02:40 (72.107.219.204)
I am restoring a pair of Heathkit W5M monoblock amps, and doing a more thorough job than a pair I had (that were excellent when completed) about 10 years ago. I have US-made 6L6GC tubes in and al .......
12: Amp/Preamp Asylum, Also... (0.00)
Posted by PeterI on 2022-04-03, 09:19:47 (97.118.65.220)
The hum is steady, low level, maybe 120Hz, not associated with inputs or affected by Vol controls. It was the same before I changed any capacitors. .......
13: Amp/Preamp Asylum, RE: Any tech guys with an Audible Illusion L1 preamp can offer help? (0.00)
Posted by PeterI on 2022-04-03, 07:56:11 (97.118.65.220)
Thanks, yes I have. And will continue to inspect closely, though there is no mechanical stress on the board. .......
14: Amp/Preamp Asylum, Thanks (0.00)
Posted by PeterI on 2022-04-03, 07:53:02 (97.118.65.220)
Thanks for advice. I was thinking those needed to be checked next. I am measuring 330VDC on most of the 14 terminals of those LM723 regulators, which can't be right. Will replace those for sure. ::: .......
15: Amp/Preamp Asylum, Any tech guys with an Audible Illusion L1 preamp can offer help? (0.00)
Posted by PeterI on 2022-04-02, 14:25:19 (97.118.65.220)
I have an Audible Illusions Modulus L1 line preamp with a hum problem. I replaced all electrolytic capacitors (in PS also) but problem persists so I'm looking for voltages around the voltage regula .......
16: Tube DIY Asylum, Thanks NT (0.00)
Posted by PeterI on 2021-11-04, 13:38:12 (70.57.27.209)
nt .......
17: Tube DIY Asylum, RE: How much current needed for a 6SN7 preamp? AE-3 (0.00)
Posted by PeterI on 2021-11-04, 13:37:22 (70.57.27.209)
Thanks. That is the exact schematic I use but will change rectification to 6V tube. Also planning to stick with AC on filaments. I wonder if there any truth to the belief that DC filaments may be qui .......
18: Tube DIY Asylum, RE: How much current needed for a 6SN7 preamp? Pic (0.00)
Posted by PeterI on 2021-11-04, 08:37:43 (70.57.27.209)
Thanks for that info. The preamp is based on the Cary AE-3, designed by Dennis Had in the 1990s. I built a similar one before so I know it "works", but I have different transformers and parts at my .......
19: Tube DIY Asylum, How much current needed for a 6SN7 preamp? (0.00)
Posted by PeterI on 2021-11-04, 07:21:55 (70.57.27.209)
I am building a tube preamp, very simple design, that uses two 6SN7s. I am digging thru my vintage power transformers for something adequate. How much mA will I need to supply? 9mA per triode? So 9 x .......
20: Tube DIY Asylum, RE: Can't find fault ... (0.00)
Posted by PeterI on 2021-10-13, 10:14:06 (75.166.201.239)
Thank you for the info. As mentioned in a post above I don't have UL operation. Screen voltage comes from the well-filtered PS after a dropping resistor of 1Kohm. Best P .......
21: Tube DIY Asylum, Can't find fault ... (0.00)
Posted by PeterI on 2021-10-09, 15:36:19 (75.166.201.239)
I just upgraded some parts on my one complete monoblock and it sounds fantastic. Now on to the 2nd one... 6P3S-E with 388v on plates and 376V on screens. Sylvania 6SN7GT's. -P .......
22: Tube DIY Asylum, The W4M Gillespie mods schematic - pic (0.00)
Posted by PeterI on 2021-10-08, 09:15:09 (75.166.201.239)
The schematic I am following except a DIY clone not actual modified W4M: .......
23: Tube DIY Asylum, RE: Series VR -Thanks (pic) (0.00)
Posted by PeterI on 2021-10-07, 12:48:12 (75.166.201.239)
Thanks for that very thorough response. And your amp looks great. Since sharing pics, here's one of the pair of monoblocks. Not my most exciting design but it looks ok. -Pete .......
24: Tube DIY Asylum, Power supply question re screens on OP tubes -pics (0.00)
Posted by PeterI on 2021-10-07, 07:56:45 (75.166.201.239)
I have a pair of mono amps I am building based on Heathkit W4M (Williamson) design but with mods suggested by Dave Gillespie. So far it is working and sounding great but I am getting 388V on the .......
25: Tube DIY Asylum, RE: Stumped about problem with hum in new amp build -Thanks (0.00)
Posted by PeterI on 2021-08-23, 02:16:03 (70.59.11.235)
Thank you gentleman, for your advice and info. I will go in further with your suggestions. My power supply pi filter is: 324-0-324 >UF4007 > 47uf > 5H choke > 120uf > 1Kohm > 50uf> 220ohm>27uf>200Kohm .......
26: Tube DIY Asylum, Stumped about problem with hum in new amp build, HF22 clone (0.00)
Posted by PeterI on 2021-08-22, 10:47:02 (70.59.11.235)
Hello friends, I'm hoping someone has a suggestion, I completed a build of an amplifier based on Eico HF-22, very similar to a successful build I did nearly 2 years ago, except using superior parts. I .......
27: Tube DIY Asylum, Thumbs up NT (0.00)
Posted by PeterI on 2021-06-25, 06:16:04 (75.166.200.186)
nt .......
28: Tube DIY Asylum, Thanks NT (0.00)
Posted by PeterI on 2021-06-23, 15:18:33 (75.166.200.186)
nt .......
29: Tube DIY Asylum, RE: phase shift vs OPT saturation Thx. Amp pics (0.00)
Posted by PeterI on 2021-06-23, 12:24:42 (75.166.200.186)
Thanks for that input. Always learning here. With another amplifier I recently built (6V6s PP in triode mode) I used that negative cathode source. But I liked the lack of NFB as well. Looks lik .......
30: Tube DIY Asylum, RE: Amplifier Bias -Thanks (0.00)
Posted by PeterI on 2021-06-23, 09:08:21 (75.166.200.186)
I see he supplies the EFB from the B+ of the SCA-35. ~350VDC? into a 2w 360Kohm R. I'm not sure I'd know how to adapt that to my HF-14 clone. He doesn't give voltages to the in and out of the LM33 .......
31: Tube DIY Asylum, Strangely, here's the Eico manual schematic: (0.00)
Posted by PeterI on 2021-06-23, 08:55:44 (75.166.200.186)
What happened to the B+ input to the OPT? (as mentioned previously). (Incidentally I did build a clone of Citation V amp. I used the Harman Kardon schematic, noting the error on the Sam's) ::: TOPI .......
32: Tube DIY Asylum, Or you could just sell it to me ... :) (0.00)
Posted by PeterI on 2021-06-23, 08:25:00 (75.166.200.186)
And I agree, the 6V6 makes great sound. Cheers -Pete Babylonart@aol.com .......
33: Tube DIY Asylum, RE: Amplifier Bias -Thanks (0.00)
Posted by PeterI on 2021-06-23, 08:21:02 (75.166.200.186)
Thanks for that advice. I always look at Dave G's designs though much content in his articles are over my head. I have used fixed bias in other builds, using this design borrowed from Jef Larson for h .......
34: Tube DIY Asylum, RE: Not sure it's an EICO HF-14 schematic... (0.00)
Posted by PeterI on 2021-06-23, 08:02:28 (75.166.200.186)
There is definitely some discrepancy between the Sams Photofact and the original Eico voltages. I will be using the Eico schematic. .......
35: Tube DIY Asylum, RE: If you are looking for better bass response... (0.00)
Posted by PeterI on 2021-06-21, 15:55:29 (75.166.200.186)
Thanks for that info. Actually, I'm imitating the Eico HF81 output, same as the HF14 monoblock amp. I've owned, worked on and restored 4 HF81s (now sold). I have some pretty good vintage OPTs. I guess .......
36: Tube DIY Asylum, Building clone amp - question about grid resistor and coupling cap (0.00)
Posted by PeterI on 2021-06-21, 09:25:55 (75.166.200.186)
Hello friends, I'm building my own version of this Eico HF14 amplifier in monoblock form, as original. I thought I'd change the coupling cap value from the minuscule .025uf (same as Eico HF81 integ .......
37: Vinyl Asylum, RE: Double check the motor pulley diameter - Thanks (0.00)
Posted by PeterI on 2020-02-07, 16:28:32 (70.59.30.214)
Yes, that's what I will likely do. But have to find the 60Hz motor/pulley. I could also try fitting a used Valhalla board to match this motor and 50Hz pulley on this project turntable but those boards .......
38: Vinyl Asylum, RE: Any US Linn LP12 gurus here? Question on motor speed - Thanks (0.00)
Posted by PeterI on 2020-02-06, 12:22:39 (70.59.30.214)
Thanks for that advice and link. Will be looking for smaller pulley or pulley/motor combo. -Pete .......
39: Vinyl Asylum, RE: Double check the motor pulley diameter - Thanks (0.00)
Posted by PeterI on 2020-02-06, 12:20:51 (70.59.30.214)
Thanks very much for that advice. I did not see info on pulley diameter on my searches. Mine measures 21mm, and dated 1980s so it is for Valhalla. I will not try to shave the pulley but will try to fi .......
40: Vinyl Asylum, Any US Linn LP12 gurus here? Question on motor speed - (0.00)
Posted by PeterI on 2020-02-05, 14:43:59 (70.59.30.214)
I have a turntable I built, which I will call a "Quasi-Linn" LP12. It is made from Linn platters, Linn sub-chassis, Linn bearing, and Linn motor with original Linn pulley. (The base, top and armboard .......
41: Tube DIY Asylum, RE: I think you should keep it PPP EL84. Thx (0.00)
Posted by PeterI on 2019-10-09, 11:20:21 (75.166.246.239)
Nice work on that amp - a beefy looking unit. Thanks for input. P .......
42: Tube DIY Asylum, I know, right? NT =B^D (0.00)
Posted by PeterI on 2019-10-07, 07:13:16 (75.166.246.239)
nt .......
43: Tube DIY Asylum, RE: Eico OPTs - Thx. HF-89 Voltage chart (0.00)
Posted by PeterI on 2019-10-05, 10:29:37 (75.166.246.239)
I see the Eico HF-89 schematic in manual supplied by Eico and I want to build that circuit with different PS. But I can't find a Sam's Photofact for HF89 with voltages anywhere. But at least the Eico .......
44: Tube DIY Asylum, RE: Eico OPTs Cit V (clone pic) (0.00)
Posted by PeterI on 2019-10-04, 10:57:13 (75.166.246.239)
Funny you should mention the H-K Citation V - one of my most successful builds was a clone of the Citation V (using Sherwood OPTs though). It was sold. As for 12BY7 and 7054 - I have bags of them (lit .......
45: Tube DIY Asylum, RE: Eico OPTs - 6P3S-E, Thx (HF87 schematic) (0.00)
Posted by PeterI on 2019-10-04, 10:37:46 (75.166.246.239)
Hey that's an idea - I have 4 or 5 6P3S-E sitting. Thanks, didn't think those would work with a 4100ohm OPT. I am looking at Eico HF-87 schematics to build (can you tell I dig the old stuff?) Not sur .......
46: Tube DIY Asylum, RE: Eico OPTs and recommended circuit question -Thanks (0.00)
Posted by PeterI on 2019-10-04, 06:39:50 (75.166.246.239)
Thanks for input Eli. I have lots of (mainly older, tested) EL84s and 6V6s but have never made a PPP amp. I have a few EL34s but will buy as needed. As for power transformer, I sell vintage transforme .......
47: Tube DIY Asylum, Eico OPTs and recommended circuit question (schematic) (0.00)
Posted by PeterI on 2019-10-03, 16:55:13 (75.166.246.239)
Hello friends. I recently acquired a pair of older output trannies from Eico HF32, a mono integrated amp from late 1950s which used PPP EL84s for 30-32 watts. According to Sam's Photofact these OPTs .......
48: Tube DIY Asylum, RE: What circuit are you following? PIC (0.00)
Posted by PeterI on 2019-08-20, 16:44:54 (70.57.30.71)
The signal section .......
49: Tube DIY Asylum, RE: Lowering gain in DIY 6L6 amplifier - Thanks (0.00)
Posted by PeterI on 2019-08-19, 17:39:05 (70.57.30.71)
Thanks for advice. I did switch to a SS Hafler DH101 preamp and hiss reduced and Volume levels are now within an adjustable range. What I was using before was a DIY tube preamp based on Dennis Had's 6 .......
50: Tube DIY Asylum, Lowering gain in DIY 6L6 amplifier - picture (0.00)
Posted by PeterI on 2019-08-19, 10:26:49 (70.57.30.71)
Hello friends. I recently completed an audio amplifier project with 6L6 tubes. It has way too much gain since music plays LOUD with the preamp Vol knob in low position. I put a 5751 tube into the 1 .......
51: Tube DIY Asylum, RE: Antek AS-2T350 - B+ voltage expected? - Thanks (0.00)
Posted by PeterI on 2019-06-14, 12:34:05 (70.59.8.222)
Thanks for that info. Pete .......
52: Tube DIY Asylum, Antek AS-2T350 - B+ voltage expected? (0.00)
Posted by PeterI on 2019-06-13, 11:27:17 (70.59.8.222)
Developing a new audio amplifier that will use 4 6P3S-E tubes, 2 channel PP, diode bridge rectification, C-L-C-C type filter. I figure the OP tubes are gonna draw 50mA per. Maybe 20 mA from other tube .......
53: Tube DIY Asylum, RE: Is a switch on B+ adding noise? Thanks (0.00)
Posted by PeterI on 2018-11-27, 14:39:48 (70.59.0.232)
Thanks for input. I used to use CL type thermistors when restoring vintage tube amps but have gotten away from it with DIY project builds using new transformers and caps. Cheers .......
54: Tube DIY Asylum, I built that phone preamp... (0.00)
Posted by PeterI on 2018-11-26, 10:18:07 (70.59.0.232)
- from that exact schematic. It was/is my best phono preamp (after some failed attempts with other clone designs because of unacceptable hum and 'ho-hum' performance). I had very few changes. It's gr .......
55: Tube DIY Asylum, Is a switch on B+ adding noise? And 5.95VDC on heaters (0.00)
Posted by PeterI on 2018-11-26, 10:01:56 (70.59.0.232)
Another question, I want to put a switch on the B+ so I can put voltage on the filaments first, then switch on HV. Does this add noise or "hash" to the B+ voltage In the PS? I have a special AC to DC .......
56: Tube DIY Asylum, It is Antek AS-05T240 (0.00)
Posted by PeterI on 2018-11-26, 03:04:34 (97.118.64.106)
I know there is a shield ground but have never seen a CT. Thanks for advice. .......
57: Tube DIY Asylum, The toroidal trans has no center tap. Problem? (0.00)
Posted by PeterI on 2018-11-26, 02:46:10 (97.118.64.106)
This toroidal transformer has no CT so will a tube rectifier work properly? Do I have to put diodes on the AC leads? Thanks Peter .......
58: Tube DIY Asylum, RE: Question about adapting 6V transf to 5V rectifier operation (0.00)
Posted by PeterI on 2018-11-25, 18:32:35 (97.118.64.106)
Good idea - 6CA4. I have some but have never wired one; much more experienced with octal rectifiers. Also, I'll be able to use 40uf or so on first cap in PS. Not sure how much voltage drop I'll see bu .......
59: Tube DIY Asylum, Thanks for suggestions (0.00)
Posted by PeterI on 2018-11-25, 18:23:21 (97.118.64.106)
I have a 6AX5, now that I think of it. I was going for 5Y3 because I have some good ones inc 6087 and also because i was trying to follow a schematic (clone of AES AE-3 DJH pre). Thanks Peter ::: TOPI .......
60: Tube DIY Asylum, Question about adapting 6V transf to 5V rectifier operation (0.00)
Posted by PeterI on 2018-11-25, 14:53:25 (97.118.64.106)
I have a 100mA toroidal transformer for a preamp project. It makes the right voltage for my B+ and has two 6.3VAC 2A windings. One 6.3V source I will use for 2 6SN7 tubes. I am wondering if the other .......
61: Tube DIY Asylum, RE: Tubes for a 26 tube preamp (0.00)
Posted by PeterI on 2018-11-25, 14:41:09 (97.118.64.106)
I have a lot of 4 26 tubes on Asylum Trader in tubes section. Old ones can be touchy as I'm sure you know. -Peter .......
62: Tube DIY Asylum, Thanks for responses... (schematic) (0.00)
Posted by PeterI on 2018-10-15, 07:05:33 (75.166.216.124)
Thanks - I learned some things, as did others reading this. I don't think I'd chance just leaving the cathode bypass caps out, in hopes that I might get some sonic benefit. But then again, this pream .......
63: Tube DIY Asylum, Best 470uf caps for cathode bypass in preamp (0.00)
Posted by PeterI on 2018-10-11, 15:03:26 (75.166.216.124)
I'm replacing several 470uf / 16V electrolytic capacitors in my older AI tube preamp with 6922s. What are the best caps for this job these days? Elna? Panasonic? They only run 3-5 VDC. Thanks for advi .......
64: Tube DIY Asylum, RE: 12BY7 (0.00)
Posted by PeterI on 2018-09-15, 16:56:36 (97.118.95.210)
I have bags of good US 12BY7s - can't give 'em away. I got them to test in my Citation V clone I built. .......
65: Tube DIY Asylum, RE: Suggestions for restore of Maggie 175 amp Thanks (0.00)
Posted by PeterI on 2018-09-10, 11:03:34 (97.118.95.210)
Thanks for that advice. As it happens I already altered the input components - no caps there, and the grid resistor at 1Kohm. I will disconnect C9 and C16. I ordered some better (new) coupling caps. .......
66: Tube DIY Asylum, RE: "Coupling caps changed from .047uf and .0033uf to all 4 .1uf." (0.00)
Posted by PeterI on 2018-09-09, 07:42:41 (97.118.95.210)
My research led to these values. Some restorers even suggested 470uf/ 63v caps on the 6V6 OP cathodes but that seemed crazy. Here's one of several modded Mag 175 amp circuits that I found (but only us .......
67: Tube DIY Asylum, RE: Suggestions for restore of Maggie 175 amp (0.00)
Posted by PeterI on 2018-09-09, 07:38:34 (97.118.95.210)
Yes, I think I will add 1000 ohm to grids because nearly all my other amplifiers have that (though I'm not sure of the advantage). Does anyone think the 470K resistors in grid-to-ground position are .......
68: Tube DIY Asylum, Suggestions for restore of Maggie 175 amp (0.00)
Posted by PeterI on 2018-09-08, 13:00:56 (97.118.95.210)
Wondering if anyone can help me with this. I acquired a 1959 Magnavox phono console 6V6 amp #185 and, wanting to recover the excellent sound of another Maggie 6V6 amp I regretted selling years ago, I .......
69: Tube DIY Asylum, RE: RCA phono stage question - (my build) (0.00)
Posted by PeterI on 2018-04-12, 07:41:16 (97.118.84.38)
Thanks. I have a B+ of 254VDC after power supply caps. But voltages at plates a bit lower than that. Cheers Pete .......
70: Tube DIY Asylum, RE: RCA phono stage question - picture (my build) (0.00)
Posted by PeterI on 2018-04-08, 12:58:38 (97.118.84.38)
Here's my version of that schematic; tried to stay close to values, etc. I know the layout is terrible but it sounds very good (I've compared a number of tube phono preamps). Have 2 older Amperex l .......
71: Tube DIY Asylum, RE: Questions about 6BG6G amp build (schematic) Grommes 216BA (0.00)
Posted by PeterI on 2017-06-21, 19:57:05 (97.124.178.119)
12FQ7 isn't a direct plug in for 12AU7 anyway. It can't run on 6V, no connection to pin 9. .......
72: Tubes Asylum, RE: Hope someone can help clear something up for me . . . (0.00)
Posted by PeterI on 2017-06-15, 06:37:29 (70.59.9.123)
That brand is Webcor. If they are long plate you can expect superb tubes and corresponding sound. The construction may match exactly, regardless of labelling. Etched codes at the base of the tubes wou .......
73: Tube DIY Asylum, Thanks (pic) (0.00)
Posted by PeterI on 2017-06-14, 18:41:01 (70.59.9.123)
My brother saw them and said "With the hot rod styling all you need now is flame decals." :0) .......
74: Tube DIY Asylum, Thanks for info NT (0.00)
Posted by PeterI on 2017-06-14, 16:10:34 (70.59.9.123)
nt .......
75: Tube DIY Asylum, This is what they look like... (pic) (0.00)
Posted by PeterI on 2017-06-14, 14:33:52 (70.59.9.123)
...in case anyone's interested. The OP transformers are small, what I have for now. They are *claimed* to be near full-range (30Hz-18kHz) as long as you don't try to push more than 25W thru them. .......
76: Tube DIY Asylum, RE: Schematic shows 5U4 5V4 (0.00)
Posted by PeterI on 2017-06-14, 10:24:22 (70.59.9.123)
Thanks for advice. I have both 5U4 and 5V4, and 5V4 gives slightly higher B+. I have GZ34 to try as well. Now at 405v plates, 1.20V at cathode, -32V at grid. Pretty close. Adjusting bias, I can get t .......
77: Tube DIY Asylum, RE: Schematic shows (0.00)
Posted by PeterI on 2017-06-14, 07:54:45 (70.59.9.123)
I want to get that higher. Still tweaking. PS: 395-0-395 > 5V4 rect > 20uf 500V film > 5H choke > B+ 403VDC > 50Uf > 900ohm 5W > 50uf > 4Kohm > 334V screen, etc etc .......
78: Tube DIY Asylum, RE: Schematic shows (0.00)
Posted by PeterI on 2017-06-14, 07:28:48 (70.59.9.123)
Yes, it's dialed in now. The schematic showed -45V at the bias source AND -45V at the grid which must be wrong, after passing thru resistors. Now have 396V on plates, about -32 to -33 on grid, and 1. .......
79: Tube DIY Asylum, RE: 6BG6G mono amp sounds great but (0.00)
Posted by PeterI on 2017-06-13, 20:47:08 (70.59.9.123)
Thanks, I was wondering if that was the calculation. The spec is supposed to be 1.2V at cathode, which would be 1.2 divided by 25ohm = .048, about right. If I turn my bias adjust all the way to the ot .......
80: Tube DIY Asylum, 6BG6G mono amp sounds great but (0.00)
Posted by PeterI on 2017-06-13, 16:14:31 (70.59.9.123)
I recently built a 6BG6G audio amplifier, first of a stereo pair, loosely based on a 1950s Grommes 216BA amp. Sounds fantastic, no distortion. My question is, the cathode voltage doesn't really measur .......
81: Tube DIY Asylum, RE: First thing I'd do is get rid of the vacuum tube rectifier Nah (0.00)
Posted by PeterI on 2017-05-29, 11:21:48 (71.212.196.9)
Nah, I've got 3 VERY good (more modern) homebuilt amplifiers with diode rectification, Cree Schottky. This is purposely an old-school build, will have a different look and sound. I have slam if I nee .......
82: Tube DIY Asylum, Anyone know the primary of those OPTs? nt (0.00)
Posted by PeterI on 2017-05-27, 18:28:24 (71.212.196.9)
nt .......
83: Tube DIY Asylum, RE: TDSL is Wrong (0.00)
Posted by PeterI on 2017-05-25, 12:58:55 (71.212.196.9)
Yeah, I knew that current draw was crazy high, but I'll have adjustments to each tube, at least that's the plan. I will measure mA at each tube. .......
84: Tube DIY Asylum, I just do what TDSL tells me to do :) - pic (0.00)
Posted by PeterI on 2017-05-25, 11:45:38 (71.212.196.9)
I believe those numbers are maximums. That's a lot of juice, will try to stay in the moderate zone. .......
85: Tube DIY Asylum, Thanks for that (0.00)
Posted by PeterI on 2017-05-25, 09:34:11 (71.212.196.9)
That's good advice - i will keep screen connections simple. Probably can convert to Triode later to see what that's like. I don't think I need a ton of power. My only triode amp (my first build) was w .......
86: Tube DIY Asylum, RE: Questions about 6BG6G amp build (schematic) Grommes 216BA (0.00)
Posted by PeterI on 2017-05-25, 08:35:57 (71.212.196.9)
Thanks for your advice on this, in particular about triode operation. I have built several amps inc 6L6GB/C and mention them below, but certainly don't expect anyone to dig thru all that. :) The plat .......
87: Tube DIY Asylum, RE: Bias transformer trick. Thanks (0.00)
Posted by PeterI on 2017-05-25, 05:56:41 (71.212.196.9)
Thanks. I would have to find a very small xformer and have 2 that match, in this case. Most of my 12V formers are for filaments, 2A+. .......
88: Tube DIY Asylum, RE: Not to beat this thing to death but can anyone address the pentode ? (0.00)
Posted by PeterI on 2017-05-25, 04:31:41 (71.212.196.9)
Thanks, I know it's a tetrode but the data sheets call it pentode mode. I see the people are tired of this thread. Time to start drilling holes in aluminum. Thx .......
89: Tube DIY Asylum, Not to beat this thing to death but can anyone address the pentode ? (0.00)
Posted by PeterI on 2017-05-24, 14:41:11 (71.212.196.9)
Question. How would other parameters change if I ran this tube in pentode mode, since i don't have UL taps. Tube specs say under 400V on the screen. Sourced from dropping B+ ? Thought I'd do triode m .......
90: Tube DIY Asylum, OPTs and FB (0.00)
Posted by PeterI on 2017-05-24, 07:30:08 (71.212.196.9)
Hi Mike, the Citation V clone amp uses OPTs from a Sherwood S8000, at 7Kohm. Not huge transformers but very sweet. I built the amp for 6L6GB and 6P3S-E and it was great but decided to try KT66, and .......
91: Tube DIY Asylum, RE: Questions about 6BG6G amp build (schematic) Grommes 216BA (0.00)
Posted by PeterI on 2017-05-23, 14:44:24 (71.212.196.9)
Thanks for that info, I have lots of 12BH7, and the other tubes. But not so sure about that much increased heater draw. Pete .......
92: Tube DIY Asylum, RE: Here is another way of doing this with a pair of chokes and a small charging cap. (0.00)
Posted by PeterI on 2017-05-23, 14:38:49 (71.212.196.9)
That's a pretty wild set up. I already built my KT66 amp, a HK Citation V clone, with Sherwood S8000 OPTs. Sounds very good, punchy and dynamic w/ new GL KT66s. I don't run them hard, 42mA at each tub .......
93: Tube DIY Asylum, RE: Questions about 6BG6G amp build (schematic) Grommes 216BA (0.00)
Posted by PeterI on 2017-05-23, 12:14:10 (71.212.196.9)
Thanks for that - actually I was studying my old (1960 original! - with voltages) Heathkit W5M manual that made me consider variations, such as higher filter choke value and the 5R4 rect. But then I'm .......
94: Tube DIY Asylum, RE: "Or, build, learn, and then decide how to apply what you learned for further improvement." (0.00)
Posted by PeterI on 2017-05-23, 08:31:47 (71.212.196.9)
I may. A surprising number of high-end preamp/amp manufacturers still use 12AU7 tubes. They aren't doing it because they're beancounters. Thanks for "input" :) .......
95: Tube DIY Asylum, Coupling cap values seem ok? NT (0.00)
Posted by PeterI on 2017-05-23, 07:20:43 (71.212.196.9)
NT .......
96: Tube DIY Asylum, RE: Questions about 6BG6G amp build Grommes 216BA - Pic (0.00)
Posted by PeterI on 2017-05-23, 07:08:06 (71.212.196.9)
Thanks very much Mike. (we go back about 10 years, I reckon). This Williamson circuit is reminiscent of my old Heathkit W5Ms (now sold), which I meticulously restored. It used 5R4s which I understa .......
97: Tube DIY Asylum, RE: Questions about 6BG6G amp build Grommes 216BA - pic (0.00)
Posted by PeterI on 2017-05-23, 06:50:14 (71.212.196.9)
That is, of course, the problem (of several) using old schematics as a guide. One can't fully know the old iron used, and what compromises were made to work around the iron's specs/shortcomings. A .......
98: Tube DIY Asylum, RE: Questions about 6BG6G amp build (schematic) bias (0.00)
Posted by PeterI on 2017-05-23, 06:37:09 (71.212.196.9)
Yes, that's good advice. I will make a small perfboard circuit w/ small Tamura trans and diode bride (not half-wave as original). I don't have a lot of real estate for another pot. 1/2W pot would be o .......
99: Tube DIY Asylum, Questions about 6BG6G amp build (schematic) Grommes 216BA (0.00)
Posted by PeterI on 2017-05-22, 21:02:33 (71.212.196.9)
I got a wild hair to build "old-timey" monoblock amplifiers from the 1950s, in part because I have a lot of the parts on hand and also because the aesthetic appealed to me. I've had very good luck .......
100: Tubes Asylum, RE: Amperex 5687 with gold pins, another OGR special (0.00)
Posted by PeterI on 2017-05-21, 10:52:56 (71.212.196.9)
You're right. The really odd tubes are his RCA and Raytheon "gold pin" tubes. Haha. Make an electro-plating bath 1/4" deep? set tubes in and plate w/ gold-ish plating? Like Radio Shack did with almos .......
101: Tubes Asylum, RE: Amperex 5687 with gold pins, another OGR special (0.00)
Posted by PeterI on 2017-05-21, 07:24:37 (71.212.196.9)
The seller does say GE branded Amperex. Printing looks authentic to the era. Of course Sylvania had their Gold tubes, some had gold pins. And while Amperex had many gold-plated pin tubes for hi grade .......
102: Tubes Asylum, RE: Question on testing 12AX7s - gm vs. mA (0.00)
Posted by PeterI on 2017-04-14, 15:17:15 (75.166.194.190)
Well, gm minimum for 12AX7 is very clear at 875, but very few read that low. As a (related) aside, I once got a boxful of used, rejected tubes (mostly Russian of various guitar amp brands) from a loc .......
103: Tubes Asylum, R prefix (0.00)
Posted by PeterI on 2017-04-06, 09:19:21 (97.122.91.31)
Does the R prefix on the printed code mean the Mitchell plant in England? It is a pretty great photo. Mil spec tubes? .......
104: Tubes Asylum, RE: Question on testing 12AX7s - gm vs. mA 539C (0.00)
Posted by PeterI on 2017-04-06, 08:35:13 (97.122.91.31)
That means lowering the grid bias to around .8-1 V. The gm goes way up, to around 1800. (I can make any poor performing tube read high that way. ) Pete .......
105: Tubes Asylum, Question on testing 12AX7s - gm vs. mA (0.00)
Posted by PeterI on 2017-04-05, 09:32:39 (97.122.91.31)
I acquired a Hickok 539c tester a while ago, calibrated by local expert. It has current measuring capability. I test a LOT of tubes but the common 12AX7 is sometimes a mystery. I get tubes that will r .......
106: Tube DIY Asylum, RE: 26 preamp to 01a - results, Pic (0.00)
Posted by PeterI on 2017-02-23, 19:40:56 (71.212.251.215)
Not that anyone gives a rat's fanny :) about my little 01A DHT tube preamp but here are my working numbers: 120V-8.5 = 111.5 8.5 / 2700 = 3.15 mA 3.15 x 112 = .347 watts. All within reasonable rang .......
107: Tube DIY Asylum, RE: 26 preamp to 01a question- Thx (0.00)
Posted by PeterI on 2017-02-20, 12:05:44 (71.212.251.215)
Thanks for the info and calculation; will apply that. Pete .......
108: Tube DIY Asylum, RE: Build the Bartola Gen 2 01A preamp- Thx (0.00)
Posted by PeterI on 2017-02-20, 12:03:03 (71.212.251.215)
Thanks for the link - I have seen that preamp but not that detailed page. It's a bit over my head. I used FETs once before in the bias circuit of an EL84 amp. I don't doubt that the Bartola pramp is t .......
109: Tube DIY Asylum, 26 preamp to 01a question (0.00)
Posted by PeterI on 2017-02-19, 15:31:47 (71.212.251.215)
I'm in the process of breadboarding this preamp design from the V-52.com site. I have good chokes in PS and steady well-filtered 1.5 to 5V DC for filaments. I decided to change from 26 to 01A, for .......
110: Vintage Asylum, RE: mil spec'ed Erection Amplifier - xformers (0.00)
Posted by PeterI on 2016-07-06, 07:14:07 (75.171.201.150)
Is that a UTC transformer? As you may know, they are in demand in the recording industry - go for a lot of money (ask me how I know). Pete .......
111: Tubes Asylum, What's with all the rust? I thought (0.00)
Posted by PeterI on 2016-06-09, 16:15:50 (71.215.120.174)
I thought you lived in our beautiful arid state of Colorado. Maybe stored in damp basement? Just kidding, but I am glad to live where everything isn't (usually) coated with rust or other corrosion. I .......
112: Tube DIY Asylum, RE: Heathkit W-5M coupling cap values were chosen for more than sonic reasons... (0.00)
Posted by PeterI on 2016-03-15, 07:51:42 (65.128.82.182)
I too made the mistake of following advice here and changing the 12AU7 to 6CG7 in my W5Ms. There was a net loss in quality. The units are sold now so it's moot. Changing 6CG7 to 12BH7 was a gain for .......
113: Tube DIY Asylum, RE: Yes, thanks. Pic of underneath (0.00)
Posted by PeterI on 2016-03-05, 13:36:20 (71.218.198.184)
Thanks, Mr. McShane. I had a vague idea about how increasing uf of coupling caps is a good thing but didn't know the calculation. I think I will go with .047, being mindful of a space limit for phy .......
114: Tube DIY Asylum, Yes, thanks. On related note, what size coupling caps .... (0.00)
Posted by PeterI on 2016-03-04, 13:04:16 (71.218.198.184)
should I replace the .025uf ceramic discs with? I used .033uf K40 silver PIOs last time. Any advantage to K40P-2A in .047uf ? Thanks for input .......
115: Tube DIY Asylum, Acceptable DC on OP tube grids in mV - HF81 (0.00)
Posted by PeterI on 2016-03-04, 11:21:07 (71.218.198.184)
I managed to get an Eico HF81 in original near-mint condition. My 3rd HF81. Brought it up slow on Variac, replaced tubes (many were low), no hum, checked all voltages, and finally put in music signal. .......
116: Tube DIY Asylum, RE: Old Pacific Transformer OPTs - and questions (0.00)
Posted by PeterI on 2016-02-16, 19:27:58 (65.128.63.244)
Thanks for that info and advice. If these OPTs are intended as line driver in a circuit, then that is probably what they should be used for. Which would be with someone else, not me. :) I did build B .......
117: Tube DIY Asylum, RE: Cap Voltage Rating? (0.00)
Posted by PeterI on 2016-02-16, 07:57:00 (65.128.63.244)
The high voltage DC after the rectifiers will be about 500V+. Not enough headroom, especially for turn-on surge. Why not use the design as shown? Your diagram shows a 0-360VAC transformer secondary - .......
118: Tube DIY Asylum, RE: Old Pacific Transformer OPTs - and questions (0.00)
Posted by PeterI on 2016-02-16, 07:09:39 (65.128.63.244)
Thanks for the link, though it is not easy calculate from 500 ohm to 8 ohm. Definite push pull, not SE; there's a red wire B+ plus typical brown and blue wires to OP tube plates. .......
119: Tube DIY Asylum, Old Pacific Transformer OPTs - and questions (pics) (0.00)
Posted by PeterI on 2016-02-15, 18:55:55 (65.128.63.244)
I wonder if anyone here can help me. I bought a pair of these large, older "Pacific Transformer" OPTs in a big lot buy and was pleased with myself finding a matching stereo pair. 6600ohm P-P pri .......
120: Tubes Asylum, Do you have test data for KT88? (0.00)
Posted by PeterI on 2016-01-25, 19:03:51 (65.128.72.25)
That's where it's listed in my 539C guide, under Euro tubes. .......
121: Tubes Asylum, RE: What OP tubes for DIY 6L6-type amplifier? (0.00)
Posted by PeterI on 2016-01-22, 09:08:56 (71.218.211.229)
Thanks. After full-wave diode rectification, 100uf (500V JJ cap) crossed with 5.5uf film cap (600V). 303-0-303VAC CT > diodes > 100uf +5.5uf > 5H choke > 100uf B+ 375VDC > 210ohm > 370VDC screens, et .......
122: Tubes Asylum, What OP tubes for DIY 6L6-type amplifier? pics (0.00)
Posted by PeterI on 2016-01-21, 12:15:07 (71.218.211.229)
I built this amplifier w/ circuit based loosely on the classic Harman Kardon Citation V amplifier. It is performing and sounding great. Currently I am using 6P3S-E tubes. They vary a bit when I .......
123: Vintage Asylum, RE: Input lines (0.00)
Posted by PeterI on 2016-01-14, 10:46:48 (71.218.211.229)
I did but it's a moot point since EVERYTHING is grounded to the chassis, including the input jacks. There's no signal ground. Adding a 3" shielded cable from jacks to the input resistors and then 4" t .......
124: Vintage Asylum, RE: Heater lines (0.00)
Posted by PeterI on 2016-01-13, 13:38:32 (71.218.211.229)
There doesn't seem to be a CT for the heater, despite what the schematic shows. I tried adding 200ohm resistors to the heater cables to ground. No effect, so I removed them. I think there is an intern .......
125: Vintage Asylum, RE: Your hum is in the signal path because it changes with volume (0.00)
Posted by PeterI on 2016-01-12, 13:41:09 (71.218.211.229)
Thanks, but there is no CT on the heater windings. I think filament AC has something to do w/ the buzz. But I tried resistors to ground and capacitors on the heater circuit to see if it changed. It di .......
126: Vintage Asylum, Problem persists. I'm done with it. (0.00)
Posted by PeterI on 2016-01-12, 09:49:54 (71.218.211.229)
Usually, when trying to track down this sorta thing, you find the magic 'trick' that solves it. Not this time, but it is better. There are about 25 ground points, circuit to the chassis. And I think t .......
127: Vintage Asylum, Thanks to responders. (0.00)
Posted by PeterI on 2016-01-10, 12:03:30 (71.218.148.167)
1. The buzz goes away when 1st input tube removed. But, of course, so does the signal. 2. The buzz goes away when treble control turned down (not shown in schematic, just "tone" - a model variation a .......
128: Vintage Asylum, RE: Question about buzz sound, vintage guitar amp (0.00)
Posted by PeterI on 2016-01-09, 13:17:44 (71.33.205.179)
Yes, there are 3 input 1/4" jacks. Did the obvious things like switch out tubes. The noise lessens when I touch the chassis, but it has been removed from the cabinet for service. The chassis is not 'h .......
129: Vintage Asylum, Question about buzz sound, vintage guitar amp (0.00)
Posted by PeterI on 2016-01-09, 11:56:26 (71.33.205.179)
I am working on friend's vintage 1960s tube guitar amp and I have repaired several problems and upgraded some parts (mainly capacitors). I have a persistent buzz that goes up and down with Vol cont .......
130: Tube DIY Asylum, RE: This old MM design (0.00)
Posted by PeterI on 2016-01-09, 11:43:38 (71.33.205.179)
Yes, better to say "didn't have enough gain for my very good but 86db speakers, and my listening habits" (loud) And the EL34s are triode mode. .......
131: Tube DIY Asylum, This old MM design - pic (0.00)
Posted by PeterI on 2016-01-09, 07:09:52 (71.33.205.179)
Poindexter's Music Machine (which I built a few years ago) used 6GK5 tubes. It didn't have enough gain. I still had to use a preamp. I realize this is a different arrangement. But it sounds good. P .......
132: Tube DIY Asylum, RE: Questions that keep me awake at night ... (input routing) (0.00)
Posted by PeterI on 2015-12-30, 06:51:03 (184.96.188.7)
Yes, did that in one of my last amp builds, the input 1st stage tubes were in the back of the amp, and the power supply up front (hidden underneath.) Thanks to responders .......
133: Tube DIY Asylum, Questions that keep me awake at night ... (input routing) (0.00)
Posted by PeterI on 2015-12-29, 11:26:14 (184.96.188.7)
OK, an exaggeration, but I am working on my 5th tube power amplifier build. Much of what I know (which ain't a lot but I do follow some good examples) is from studying vintage tube amps. I have notice .......
134: Tube DIY Asylum, Thanks for reminders. Should OPT Sec neg go to signal ground? (0.00)
Posted by PeterI on 2015-12-25, 16:48:21 (184.96.180.191)
-or to chassis? I presume to the signal ground. I have used 10 to 100 ohm from floating signal ground to chassis in the past. Thanks for the tips for us amateurs still learning. Pete .......
135: Vintage Asylum, Thanks, and same to you Mike :) nt (0.00)
Posted by PeterI on 2015-12-25, 16:41:29 (184.96.180.191)
nt .......
136: Tubes Asylum, 12AU7 (0.00)
Posted by PeterI on 2015-11-17, 15:02:36 (184.96.163.187)
The experienced fellows and builders I know who really know audio design howl with laughter at the mention that 12AU7 is a 'bad' tube. So many great classic, proven amplifier designs used 12AU7 as the .......
137: High Efficiency Speaker Asylum, Thanks for info! NT (0.00)
Posted by PeterI on 2015-10-24, 07:52:13 (174.29.3.239)
nt .......
138: High Efficiency Speaker Asylum, RE: Jensen XP-101s (0.00)
Posted by PeterI on 2015-09-23, 20:18:12 (174.29.179.117)
Thanks. I managed to get them apart. They are OK inside. The parts are unusual and very precise. The tape idea is a good one. Pete .......
139: High Efficiency Speaker Asylum, Jensen XP-101s (0.00)
Posted by PeterI on 2015-09-23, 16:43:09 (174.29.179.117)
I have a pair of Jensen XP-101 horn drivers that function and produce sound but looking inside, have some corrosion - a bit of rust and aluminum corrosion. Diaphragms are intact. Not many here have p .......
140: Vintage Asylum, RE: Great amps!!! 6P3S-E (0.00)
Posted by PeterI on 2015-06-21, 09:11:18 (174.29.70.146)
The Russian 6P3S-E tubes were in them when I sold my W5Ms. They were great - stable in circuit, punchy and musical. Bias balance easy to adjust. Pete .......
141: Tube DIY Asylum, Thanks. NT (0.00)
Posted by PeterI on 2015-05-16, 21:06:25 (75.166.173.50)
nt .......
142: Tube DIY Asylum, RE: Filament Windings (0.00)
Posted by PeterI on 2015-05-16, 10:15:39 (75.166.173.50)
Yes, the power tranny, being older, has 5V supply. Was going to use a (physically) small, low current tranny for the bias. I can also supplement the 6.3 VAC filament supply with an extra tranny, but p .......
143: Tube DIY Asylum, RE: CCS (0.00)
Posted by PeterI on 2015-05-14, 08:13:21 (75.166.173.50)
Thanks. I used 10M45S in my first amplifier build 3 years ago, the "Music Machine" triode EL34 version. Nice sound but not nearly enough gain. I had to use a preamp, which defeated the purpose, so it .......
144: Tube DIY Asylum, RE: A500 - changing phase splitter tube (0.00)
Posted by PeterI on 2015-05-14, 08:03:43 (75.166.173.50)
If you change phase splitter from 6CG7 to ECC99 (12BH7) what else do you have to change (besides heater pin wires)? .......
145: Tube DIY Asylum, RE: What I have so far (0.00)
Posted by PeterI on 2015-05-13, 11:48:59 (75.166.173.50)
I certainly agree about voltage doubler PS - so many classic tube amps used them, Harman Kardon, Marantz, etc. But I'm trying to work with parts I have. I don't have a 220VAC output power tranny. And .......
146: Tube DIY Asylum, What I have so far (picture) (0.00)
Posted by PeterI on 2015-05-13, 08:46:49 (75.166.173.50)
Instead of putting tubes on top like I usually do, I could gut this old Hewlett Packard test instrument case, and put everything inside, w/ ventilated top. (tried to sell the HP nixie electronic co .......
147: Tube DIY Asylum, Thanks. Will keep a note of this. nt (0.00)
Posted by PeterI on 2015-05-12, 21:02:08 (184.96.174.19)
nt .......
148: Tube DIY Asylum, RE: Anyone ever build a clone of Citation V? (0.00)
Posted by PeterI on 2015-05-12, 19:18:21 (184.96.174.19)
Thanks for suggestions. Of course, implementing them would result in an amplifier that had nothing in common with a Citation V. I have 12BY7s, 6CG7, 5881s, lots of 12BH7 (ECC99) etc. The point of foll .......
149: Tube DIY Asylum, Anyone ever build a clone of Citation V? (schematic pics) (0.00)
Posted by PeterI on 2015-05-12, 11:45:21 (184.96.174.19)
Has anyone tried to build a clone of a Citation V tube amp? It seems you could use 5881s (or 6L6WGB) instead of the original 7581s. The OP trannies wouldn't be the same but you could maybe find .......
150: Vintage Asylum, My info doesn't apply. They can be great amps tho. NT (0.00)
Posted by PeterI on 2015-04-05, 17:28:44 (174.29.11.235)
nt .......
151: Vintage Asylum, RE: Magnavox 6bq5 tone issues. (0.00)
Posted by PeterI on 2015-04-05, 12:35:45 (174.29.11.235)
This is something that developed? The Maggie console amps have some capacitors that were meant to tailor the sound to the built-in console speakers. Normally those are removed if the amp is to be used .......
152: Tube DIY Asylum, Amazing. Here's my humble offering (picture) (0.00)
Posted by PeterI on 2015-03-01, 07:09:06 (174.29.176.242)
Cree schottky diode bridge for monoblock amplifiers (I made two). Pete .......
153: Vintage Asylum, Yes, a men's singing group from Cornell Univ., early 60s. NY (0.00)
Posted by PeterI on 2015-01-12, 09:51:04 (174.29.164.69)
I think I see a gold-faced Pilot amplifier on the shelf. Pete .......
154: Vintage Asylum, RE: 7199/6GH8A - 6U8A Adapters - improved? (0.00)
Posted by PeterI on 2015-01-06, 13:00:59 (75.166.163.146)
I see your big teflons there. Hope they are great in your Sherwood. I may give the 6GH8 thing a try. I wonder if 6BL8s would work as well, very close. The 6P14P-EB are fantastic in my S5000 (bought .......
155: Vintage Asylum, RE: 7199/6GH8A - 6U8A Adapters - improved? (0.00)
Posted by PeterI on 2015-01-06, 08:29:18 (75.166.163.146)
I have the same set up. The original Sherwood/Sylvania 7199s test very high and sound good and I had no plan to change, but wondered about the conversion kits. Thanks for the info - you think it actua .......
156: Vintage Asylum, RE: This whole Sherwood S5000 craze... (HF81 pic) (0.00)
Posted by PeterI on 2014-12-08, 04:04:41 (174.29.169.20)
I have both Sherwood S-5000 and Eico HF-81, both nicely restored. I think the Eico edges the Sherwood by a very small margin. It has a slightly 'fuller' sound; the Sherwood a bit 'clearer'. That said, .......
157: Tubes Asylum, RE: Question for EICO 667 tester experts. (0.00)
Posted by PeterI on 2014-11-25, 16:24:58 (71.33.200.6)
This may be encouraging: When I tested some older used US Tung-Sol 6550s they were around 88-90% on my Eico 667, a bit disappointing. But when I got the Hickok tester the same tubes tested very high, .......
158: Tubes Asylum, RE: Film cap off rectifier - Go square (picture) (0.00)
Posted by PeterI on 2014-09-14, 16:38:07 (71.218.158.80)
Do you have room for a 3/4" thick box? Size 41mm x 44mm x 20mm. These box Panasonic film caps are available from Mouser. Good price too. Pete .......
159: Vinyl Asylum, RE: Dual 1019 Coming Along (0.00)
Posted by PeterI on 2014-08-25, 11:14:13 (71.33.198.207)
That looks great. Really solid looking. I just junked (disassembled) a 1019 but I see you don't need any of the parts. Pete .......
160: Vintage Asylum, Thanks, all. NT (0.00)
Posted by PeterI on 2014-08-16, 21:32:53 (71.33.198.207)
nt .......
161: Vintage Asylum, Haffler 220 PS (picture) (0.00)
Posted by PeterI on 2014-08-14, 11:49:36 (71.33.198.207)
I just put larger 15,000uf PS capacitors in this all-original Hafler DH-220 SS power amplifier, from the original 10,000uf. Voltages are good throughout the driver boards, current dialed in. Sound .......
162: Tubes Asylum, RE: Calling BS on tube audio charlatans (0.00)
Posted by PeterI on 2014-08-07, 15:34:28 (174.16.223.186)
So this Chris Found is known as the supposed UK Beard expert? That's even worse, he's using his position to rip off customers. I wouldn't even mention it if just a minor technical error from an amateu .......
163: Tubes Asylum, yes, tube matching important (0.00)
Posted by PeterI on 2014-08-07, 12:17:27 (174.16.223.186)
and I am VERY glad I acquired a tester that allows me to get much more accurate gm readings and current draw. I included the whole paragraph as evidence of the (liar's) position as a service tech. : .......
164: Tubes Asylum, RE: Calling BS on tube audio charlatans (0.00)
Posted by PeterI on 2014-08-07, 09:40:35 (174.29.1.68)
Ha - "eviscerate". It's normally a friendly group, full of interesting and exotic gear (including DIY) from all over the globe, Eastern Europe, Asia, UK, etc. The offending post is from the UK and a .......
165: Tubes Asylum, Calling BS on tube audio charlatans (0.00)
Posted by PeterI on 2014-08-07, 09:19:00 (174.29.1.68)
Here's a direct quote from a man posting on a facebook tube audio page. I know people here on this august tube forum are dismissive of FB audio groups and here's possibly why. This sort of misinformat .......
166: Vintage Asylum, There's a coupla Sherwood tuners not far from me ... (0.00)
Posted by PeterI on 2014-07-29, 20:11:11 (71.218.152.22)
In Denver, though. S-2200 and S-3000. Pete .......
167: Tube DIY Asylum, RE: I think 12AY7 ? in Spring 2011. (0.00)
Posted by PeterI on 2014-07-25, 13:35:30 (174.29.190.53)
But we are getting off the thread's purpose. :) Cheers .......
168: Tube DIY Asylum, RE: ** Thank you all very much ** I think I sold you (0.00)
Posted by PeterI on 2014-07-25, 12:12:57 (174.29.190.53)
...some tubes once. I remember your name and Belgium. Best of luck with your projects. Pete .......
169: Vintage Asylum, RE: Scans of the brochure (0.00)
Posted by PeterI on 2014-07-21, 10:53:52 (174.29.190.53)
That's great - thanks for posting. Never saw the tech brochure for my Sherwood before. I like how someone drew a stylus in a record groove in an attempt to explain something about stereo tracking. .......
170: Vintage Asylum, RE: Sherwood S5000 - heat destroying wires?? (0.00)
Posted by PeterI on 2014-07-17, 19:05:15 (174.29.190.53)
You've got some real danger of shorting there. Possibly it's shorting that caused current overdraw, over-heating, and oxidation of cable insulation. Those filament wires look bad (high resistance). Ha .......
171: Vintage Asylum, That's what I'd do. nt (0.00)
Posted by PeterI on 2014-07-16, 07:51:39 (174.29.190.53)
nt .......
172: Vintage Asylum, RE: As a mid-century Modern dealer... (nostalgia) (0.00)
Posted by PeterI on 2014-07-16, 07:49:14 (174.29.190.53)
Weirdly, people like the sound of those old consoles, mainly because of nostalgia. Their parents had one when they were growing up, it was when they first 'discovered' music, that overly-warm midrange .......
173: Vintage Asylum, As a mid-century Modern dealer... (0.00)
Posted by PeterI on 2014-07-15, 12:00:23 (174.29.190.53)
...I can tell you it's a nice piece and an excellent time capsule item for someone decorating their home in MCM style. But obviously the seller has a delusion about price. Worth about $200-250 because .......
174: Vintage Asylum, RE: Gold Marantz SC-7 - Picture of Gold SC-9 (0.00)
Posted by PeterI on 2014-07-07, 14:54:30 (71.218.153.166)
This was mine. It was nothing special acoustically but definitely collectible. .......
175: Vintage Asylum, RE: Pioneer SPEC-4 - Picture of the inside NT (0.00)
Posted by PeterI on 2014-07-07, 08:03:56 (71.218.153.166)
nt .......
176: Tubes Asylum, RE: KT88Z Ia1 26 mA ? (0.00)
Posted by PeterI on 2014-07-01, 07:27:30 (75.166.189.207)
That current draw isn't all the tubes will do, it just means that on that particular tester, and at that tester's settings, each tube drew 26mA. It's more for matching than actual full-power current r .......
177: Vinyl Asylum, RE: Needed: Linn Sonndek platters (inner and outer). Thanks ... (0.00)
Posted by PeterI on 2014-06-28, 21:56:16 (174.16.216.196)
Thanks for input but we're no closer to finding parts. Not fussy, used will do. Buying new isn't an option. best .......
178: Vinyl Asylum, Needed: Linn Sonndek platters (inner and outer) (0.00)
Posted by PeterI on 2014-06-27, 17:35:40 (174.16.216.196)
I have a Linn Sondek LP12 turntable that is missing both the inner and outer platter. If you have a set you are willing to part with (maybe spares left from an upgrade), please contact me off-list. Th .......
179: Tubes Asylum, Thanks for info ... (0.00)
Posted by PeterI on 2014-06-01, 10:07:28 (174.29.27.63)
Thanks for the info. That link doesnt go anywhere for me, I did manage to find a bit of info from digging a little deeper. Apparently, it's some sort of "vibrator" circuit for test equipment. Nothi .......
180: Vintage Asylum, RE: Garage sale find - Well done. (0.00)
Posted by PeterI on 2014-05-30, 15:17:08 (174.29.27.63)
Frugality isn't the whole story of the vintage hobby but it's certainly a part. For me today, I found a mint cast-frame Jensen 12" coaxial speaker, and 2 Shure M7 phono cartridges (vintage, so who kn .......
181: Tubes Asylum, Anyone seen one of these? a SS tube? picture (0.00)
Posted by PeterI on 2014-05-30, 12:52:23 (174.29.27.63)
This "tube" looks like some sort of plug-in for a vacuum tube, or just a SS part that uses a 9 pin base. Anyone know what it is? search found nothing. Rectifier? Labelled 'Engineered Electronics On .......
182: Vintage Asylum, RE: What did you do to the three big cans on top? Fisher (0.00)
Posted by PeterI on 2014-05-29, 13:44:44 (174.29.27.63)
With the three Fisher units I did years ago, none of the can caps needed replacement after reforming. They measured good, with no hum. I didn't want the chassis to have a big kluge, with new electroly .......
183: Tube DIY Asylum, SET amplifier. GetSetGo 6B4G pic (0.00)
Posted by PeterI on 2014-05-29, 08:39:15 (174.29.27.63)
Thanks. I followed the diytube PCB plan pretty closely. Sure saves time to not go point-to-point. I am not a good woodworker - the base is from an early 70s Kenwood turntable. The vented aluminum .......
184: Tube DIY Asylum, RE: It's the last day of school.- Summer (SET pic) (0.00)
Posted by PeterI on 2014-05-28, 16:20:31 (174.29.27.63)
As a (retired) veteran teacher, I know the feeling . Have a great summer. - Pete And here's my first SET build - from the Shannon Parks PCB for 6B4G tube, called "GetSetGo'. .......
185: Vintage Asylum, Those Sumiko MMT tonearms are (0.00)
Posted by PeterI on 2014-05-22, 06:31:06 (174.29.74.61)
EXCELLENT. I've had 2 over the years. cheers .......
186: Vintage Asylum, RE: So this is it? SR71s (0.00)
Posted by PeterI on 2014-05-21, 07:54:32 (174.16.215.20)
I think very good, the crossover is not too complex, but very refined by the designer. My analysis is minimal - i don't have 'golden ears' but I do a lot of listening. My office/workshop is also not .......
187: Vintage Asylum, RE: So this is it? SR71s pic (0.00)
Posted by PeterI on 2014-05-20, 16:22:40 (174.16.215.20)
I know you weren't asking me but I'll interject anyway. I built the Zapf SR71s this winter and recently got the veneer on. They are my best speakers, and I have owned a lot. Up until now, my best stan .......
188: High Efficiency Speaker Asylum, RE: Looks like a perfect match for an open baffle...Thx (0.00)
Posted by PeterI on 2014-05-20, 12:32:12 (174.16.215.20)
Hey, that looks good and lots of info. I have some thick particle board I could rough together first. Thanks, seems do-able. That shelf on top could even support a small tweeter (If it didn't need to .......
189: High Efficiency Speaker Asylum, Q ts appears to be 0.67 acc. to EV specs. Thx. nt (0.00)
Posted by PeterI on 2014-05-19, 09:38:48 (184.96.174.252)
nt .......
190: High Efficiency Speaker Asylum, Anyone built speakers with these EV SP12C woofers? (pic) (0.00)
Posted by PeterI on 2014-05-19, 07:41:12 (184.96.174.252)
Has anyone built speakers with these EV SP12Cs? They are from around 1981, ferrite magnet. The whizzer cone removed and dustcap put in. They function and sound very good. Electro-voice specs say 100d .......
191: Tubes Asylum, one of my tube buys (0.00)
Posted by PeterI on 2014-05-16, 07:34:44 (184.96.189.138)
... since we're showing off. Of course, you can't see most of the numbers, but it was sweet. Lotsa NOS. Peter .......
192: Tubes Asylum, RE: Mullard and Tele and Amperex, Oh My! (0.00)
Posted by PeterI on 2014-05-15, 13:40:40 (184.96.189.138)
A recent bulk find? Pulls from test equipment? a good bunch o' tubes. .......
193: Vintage Asylum, Not a poor design, it's just 55 years old. (0.00)
Posted by PeterI on 2014-05-05, 08:05:10 (174.29.29.129)
and with years of rough handling, likely. .......
194: High Efficiency Speaker Asylum, Specs (0.00)
Posted by PeterI on 2014-05-04, 07:22:26 (174.29.29.129)
Yes, Have done research and found very little, except that some have tried OB with them. The model is HF12 PC-H. Thanks for info and opinions. May be a "silk purse/sow's ear" thing but I'll give it a .......
195: High Efficiency Speaker Asylum, Thanks... (0.00)
Posted by PeterI on 2014-05-03, 17:59:10 (174.29.29.129)
I think people have also used OB, but that would really be a new direction for me. A sealed box? I think of low-powered tube amplifiers usually going into ported boxes. Pete .......
196: High Efficiency Speaker Asylum, That's pretty cool ... (0.00)
Posted by PeterI on 2014-05-03, 11:45:09 (174.29.29.129)
I know these Utah speakers aren't exactly something to write home about, but I figure someone has made enclosures to get the best from them. I think i'd probably use different HF drivers, though I k .......
197: Vintage Asylum, Haha - yes, the best sounding battery charger I own. (0.00)
Posted by PeterI on 2014-05-03, 02:37:53 (174.29.29.129)
Vintage Tung Sol 5881s in there now. :) all best Pete .......
198: Vintage Asylum, Tube layout - diagram (0.00)
Posted by PeterI on 2014-05-02, 15:20:34 (174.29.29.129)
Eico HF81 tubes .......
199: Vintage Asylum, RE: Eico HF81 hookup (picture) (0.00)
Posted by PeterI on 2014-05-02, 13:45:32 (174.29.29.129)
Come on - show a little spirit, and be resourceful. There's always a solution. You are experiencing what we call "Buyer's Remorse". You'll get the amplifier going. You said the previous owner had ma .......
200: High Efficiency Speaker Asylum, Want to build Hi Ef speakers with these Utah drivers (picture) (0.00)
Posted by PeterI on 2014-05-02, 12:30:06 (174.29.29.129)
I could use some advice from this august group. I am planning to build a 3W tube amp so I had my eye open for some vintage speaker drivers, and found this pair Utah HF12P coaxials locally for cheap .......
201: Vintage Asylum, RE: How to remove honeycomb cover from Eico HF81 (0.00)
Posted by PeterI on 2014-05-02, 12:07:45 (174.29.29.129)
You may have 2 to 4 screws on back, 2 upper corners and 2 lower. Once screws are removed, the gold perforated cover should slide backwards off. If someone jammed it, it may remove with difficulty. .......
202: Vintage Asylum, RE: Eico HF81 hookup (picture) (0.00)
Posted by PeterI on 2014-05-02, 11:59:33 (174.29.29.129)
Tre shows the original label for back. 1 and 2 correspond to Left and Right here's what mine looks like on back: top 2 RCA jacks are Aux 1. So you got your HF81 finally? Hope it works terrific for .......
203: Tube DIY Asylum, Transcendar. (0.00)
Posted by PeterI on 2014-04-30, 10:21:20 (75.166.168.179)
Those look very good. It just happens I stumbled upon those today. (I remember Transcendar from the research I did for my PP amps). 160 clams is a lot for me, at least for something specialized and e .......
204: Tube DIY Asylum, Yes, that one. Thx. Primary inductance question? (0.00)
Posted by PeterI on 2014-04-30, 09:35:35 (75.166.168.179)
I am not used to working with single-ended. The only other SE amplifier I had was a small Magnavox 6bq5 from a 1960 console; that was sorta nice for low volume listening. Those OPTs may be it, but I t .......
205: Tube DIY Asylum, RE: If I put an 8ohm speaker on this SE OPT, what impedence... (0.00)
Posted by PeterI on 2014-04-29, 11:59:24 (75.166.168.179)
Thanks for help. I think I will email Edcor. The amp kit from diytube actually specifies 3.5K imp. It's a fairly simple design. Ideally, I'd need 3.5Kohm, for 8 ohm spkr, 5-10W, (full range, of cours .......
206: Vintage Asylum, RE: Bozak LS 350A (picture) (0.00)
Posted by PeterI on 2014-04-29, 09:27:19 (75.166.168.179)
Here's a pair of Bozak LS 350s I sorta wish I still had. I wasn't crazy about them at the time (2006) but now, with my better amplifiers and some 'freshening', I'll bet they would be great. Bumpy p .......
207: Tube DIY Asylum, If I put an 8ohm speaker on this SE OPT, what impedence... (0.00)
Posted by PeterI on 2014-04-29, 06:48:48 (75.166.168.179)
will the amplifier see? I am thinking of Edcor OPTs for an SE project with 6B4G tubes. They don't make 8ohm in this style, but you sure can't beat the price for their offerings. 8 ohm HE speaker, 5K .......
208: Shady Lane, Beware of R Belanger, M Uttley, etc Canada. (0.00)
Posted by PeterI on 2014-04-26, 11:30:59 (174.16.200.32)
If selling on ebay or other forums, don't sell to anyone going by Roxanne Belanger, M&H Uttley. This person has been identified before but with different names. Will not use Paypal but promises Canad .......
209: Vintage Asylum, It was intended for RCA salesmen. nt (0.00)
Posted by PeterI on 2014-04-26, 02:56:35 (174.16.200.32)
nt .......
210: Vintage Asylum, There's a cautionary tale here for us collectors. (0.00)
Posted by PeterI on 2014-04-25, 12:11:17 (174.16.200.32)
This fellow will make a LOT of money selling this stuff. But 1. Obviously the gear isn't being used or enjoyed by him. 2. It's a burden now, and what doesn't sell will become a burden to his kids, et .......
211: Tubes Asylum, RE: These are the ultimate 6550/KT88 IMHO (0.00)
Posted by PeterI on 2014-04-23, 07:47:40 (71.33.201.148)
I'm sure you saw my 4 T-S 6550s for sale (3 hole gray plates). Hey, I gotta pay the bills! Pete .......
212: Tubes Asylum, RE: Even those with 100% FB, can make you wonder..Take a look at this, (0.00)
Posted by PeterI on 2014-04-22, 14:24:28 (71.33.201.148)
I buy, sell, and handle a LOT of tubes, and I find used tubes in boxes all the time. When the servicer replaced the tubes he put the old tubes in the new boxes. Decades later they are discovered with .......
213: Vintage Asylum, Speaking of S-5000s.... (bias and current measurement) picture (0.00)
Posted by PeterI on 2014-04-19, 10:30:41 (174.29.167.32)
Since airtime seems to have solved the problem, I'll risk hijacking this thread with a question: I'm measuring -18.5 volts at the grid of OP tubes, pin 2. This is after raising the value (resistanc .......
214: Vintage Asylum, RE: Estate Sale Find ... well done (0.00)
Posted by PeterI on 2014-04-17, 15:41:58 (174.29.167.32)
It's always good to be vigilant at those sales. You never know what's hiding under a table. Like an Eico HF81. Good find - I'm looking for 2 D-130s. Very likely a homemade cabinet. Pete .......
215: Tubes Asylum, Looking for 2 RCA 7189 tubes. Does anyone... (0.00)
Posted by PeterI on 2014-04-09, 09:05:40 (174.29.89.203)
have a source for these? I have good things to trade. Contact me off-list. Cheers Pete 6922 6DJ8 12AX7 euro 6CA7 KT77 5814 5AR4 6V6 6AQ5 6SL7GT EL84 VT-231 7199 12BH7 26 01A .......
216: Tubes Asylum, RE: My homemade EL34 amp sounds better with 5881s. Also... (0.00)
Posted by PeterI on 2014-04-02, 14:58:08 (71.218.144.31)
Thanks Mike. I knew I was pushing it at over 400V on plates. I have 40% UL tap on Edcor OPTs. And there's 412V on those screens thru 150 ohm R. I had looked at the datasheets for 5881 and 6L6WGB but .......
217: Tubes Asylum, My homemade EL34 amp sounds better with 5881s (0.00)
Posted by PeterI on 2014-04-02, 13:38:39 (71.218.144.31)
I was a little apprehensive to put these old US Tung-Sol 5881-6L6WGB in this amplifier (based on the diyAudio "Ella" design). I thought the operating points would be wrong. But I can adjust each tube .......
218: Tubes Asylum, RE: 7189As in Sherwood S5000. B+ ? (0.00)
Posted by PeterI on 2014-03-30, 18:57:10 (71.218.144.31)
Hi Mike, I didnt pay that much. You mean they were original, unrestored S500o going for 800 clams? I recover some of my investment by selling the Telefunken tubes; I have no shortage of excellent 12A .......
219: Tubes Asylum, Thanks for the info. another picture (0.00)
Posted by PeterI on 2014-03-30, 16:50:51 (71.218.144.31)
Does this picture, showing construction, make the manufacturer of these tubes clearer? Russian? 7189A .......
220: Tubes Asylum, 7189As in Sherwood S5000, picture (0.00)
Posted by PeterI on 2014-03-30, 13:23:54 (71.218.144.31)
I live a charmed life. On the same week that I buy a Sherwood S5000 locally (but paid a premium price since it was pristine and unmolested), I go to the local once-a-year audio and electronics show .......
221: Vintage Asylum, Thanks ... S5000 and SR71 speakers (0.00)
Posted by PeterI on 2014-03-27, 16:18:57 (71.218.144.31)
Thanks Charles. I do my own soldering but will probably borrow some ideas from your's - and respectfully use Mike's ideas. Do you use your S5000 with the SR71s speakers? Pete .......
222: Vintage Asylum, I'm going to be looking at your's and airtime's pictures since ... (0.00)
Posted by PeterI on 2014-03-27, 15:34:25 (71.218.144.31)
I have a Sherwood S5000 again. I had one in 2006 and sold it in 2007 because my Eico HF81 was better but thought it would be fun to try again. Cheers, Sherwood users Pete .......
223: Tube DIY Asylum, Another capacitor question: Western Electric .1 (picture) (0.00)
Posted by PeterI on 2014-03-26, 15:46:50 (71.218.144.31)
About 18mm long, red ends. Western Electric logo. No indication of voltage, but they are small - can't be much. Thanks .......
224: Tube DIY Asylum, RE: Lovely looking caps...with plastic insulation wrap, too... (0.00)
Posted by PeterI on 2014-03-25, 12:21:47 (71.218.144.31)
Yeah, I'm not convinced they are PIO. They are 300V and 1/4" diameter. Thanks for responses. I need .1uf for my Eico HF81 tone section. Right now there are black 630V Solens put in by previous owner. .......
225: Tube DIY Asylum, vintage Westcap capacitors - paper in oil? (picture) (0.00)
Posted by PeterI on 2014-03-25, 07:10:35 (71.218.144.31)
I have these small Westcap capacitors .01uf 300V, removed from older gear. They have glass ends and metal cylinders. Are they paper in oil like Vitamin Q's? they sure look similar. They all measur .......
226: Tubes Asylum, Yes, good idea. NT (0.00)
Posted by PeterI on 2014-03-22, 06:20:32 (174.29.74.245)
nt .......
227: Tubes Asylum, Thanks Mike. i agree. NT (0.00)
Posted by PeterI on 2014-03-22, 06:18:58 (174.29.74.245)
nt .......
228: Tubes Asylum, RE: 307A (VT-225) tube -data sheet link (0.00)
Posted by PeterI on 2014-03-21, 14:02:13 (174.29.74.245)
The filaments have continuity but we just don't have the correct settings. 307A isn't even listed in Hickok's special WE data. below is link to picture and pinout. Thanks .......
229: Tubes Asylum, 307A (VT-225) tube (0.00)
Posted by PeterI on 2014-03-21, 12:57:21 (174.29.74.245)
Hi Thanks for info, unfortunately no result. The filaments didn't light, so it's those 1st two letters that have to connect the filament pins. I can't find another corresponding tube with same pinout .......
230: Tubes Asylum, Quick one: Does anyone have Hickok 539C test data for 307A (VT-225) tube? (0.00)
Posted by PeterI on 2014-03-20, 12:19:35 (174.29.74.245)
Thanks .......
231: Tube DIY Asylum, I just got 3 of those for a project. (0.00)
Posted by PeterI on 2014-03-18, 07:51:42 (75.166.180.74)
They are huge, but at least they lay flat. My restored HF81 already has a 1st 30uf poly. On another note, the damn thing is still my best amplifier, but runs so hot. Power transformer will burn your h .......
232: Tube DIY Asylum, Thanks ... (0.00)
Posted by PeterI on 2014-03-12, 12:20:57 (174.29.189.140)
those are useful posts on the diyAudio board. there is a lot of extraneous stuff in those 144 pages which I won't dig through, especially those octal/6V6 version posts all mixed in. Pete .......
233: Tube DIY Asylum, Changes in PS (0.00)
Posted by PeterI on 2014-03-12, 08:59:01 (174.29.189.140)
I have toroid power transformers (will be underneath) with no CT so will be using diode bridge. also I have nice old 5Hy chokes (shiny) I want to add after first PS capacitor. I just saw your revis .......
234: Tube DIY Asylum, Is there any advantage to using this adjustable bias circuit? (0.00)
Posted by PeterI on 2014-03-12, 08:19:49 (174.29.189.140)
this is from Bas Horneman's page for his BH build. .......
235: Tube DIY Asylum, RE: Yes... just finished mine .. (0.00)
Posted by PeterI on 2014-03-12, 06:59:22 (174.29.189.140)
Thanks. eager to hear one of these. That is good to know that the schematic 'worked' and gave you what you wanted and like. If you had any problems please let me know how you solved them, thx. I have .......
236: Tube DIY Asylum, Thanks very much Mr Gingertube ... (0.00)
Posted by PeterI on 2014-03-12, 06:56:06 (174.29.189.140)
for the pictures and information. I was wondering what the plate voltage to 12AX7 was, and what voltage I needed to the CCS, since I won't have a 5V transformer for CCS and would need to make the targ .......
237: Tube DIY Asylum, Has anyone built this version of so-called 'Baby Huey' EL84 amp lately? (pictures) (0.00)
Posted by PeterI on 2014-03-11, 16:15:32 (174.29.189.140)
I have these schematics below and would like to build monoblock versions. I know there are more complicated versions but this design looks like something I can handle. The reason I bring it up is I'd .......
238: Vintage Asylum, I had one in 2006. (0.00)
Posted by PeterI on 2014-03-08, 11:37:05 (75.166.178.56)
I remember it was real tight for space underneath, but since it sounded so good I didn't need to change much. The white and gold front never appealed to me much, but certainly excellent amplifier .......
239: Tubes Asylum, RE: Strangely.... (Mike, 666) (0.00)
Posted by PeterI on 2014-03-03, 09:06:01 (184.96.181.125)
The test settings should account for that. By chance I found some completely different settings that seem to be correct, 'obsolete tube' data for Eico 666. Of 3 6B4's -- 2 tubes good, one a little l .......
240: Tubes Asylum, Strangely.... (0.00)
Posted by PeterI on 2014-03-02, 16:25:01 (184.96.181.125)
I tested several 6B4Gs on my Eico 666 using data from Coletronics chart and they all tested short on the same pin, leading me to believe the data is wrong; wouldn't be the first time. They can't all b .......
241: Tube DIY Asylum, No, a project preamp. (0.00)
Posted by PeterI on 2014-02-20, 05:36:17 (71.218.141.179)
I changed the power tranny. (no C20 around here since 2011). Do you still use the formula 1.41 to get DC after tube rectification, minus the voltage drop of 15 to 20V for the 6X4 tube? If so, pwr tr .......
242: Tubes Asylum, Is this what's meant by "3 hole" Sylvania 6SN7? (picture) (0.00)
Posted by PeterI on 2014-02-19, 11:59:32 (71.218.141.179)
I have a couple of these: taller glass, code 0 26, 6SN7GT. Not NOS though. thanks for info Pete .......
243: Tube DIY Asylum, Thanks 6X4 etc (0.00)
Posted by PeterI on 2014-02-18, 14:47:11 (184.96.178.156)
Yes, I believe in Schottky diodes since I just used them in my big KT88/6550 amp I recently finished. The main reason I may try 6X4 is because this clone of 'Audio Note M7' preamp (with 5687 or 7119 .......
244: Tube DIY Asylum, PSUD doesnt work on Macs. (0.00)
Posted by PeterI on 2014-02-18, 08:38:23 (184.96.178.156)
May get access to a Windows laptop. Thanks anyway. I'm in the ballpark. .......
245: Tube DIY Asylum, Quick question: what DC voltage can I expect from... (0.00)
Posted by PeterI on 2014-02-18, 07:41:29 (184.96.178.156)
a 185-0-185 VAC CT transformer into a 6X4 rectifier tube to 40uf C-L-C? I know there will be a voltage drop but not sure how much. I'm calculating ~250VDC B+ after the 6X4 . This is for a preamp. Tha .......
246: Tube DIY Asylum, That did it, thanks (0.00)
Posted by PeterI on 2014-02-16, 14:03:52 (184.96.178.156)
It was the whole Blue/Brown lead to plates orientation thing, which wasn't shown clearly on the schematic. (The problem with having a red-colored amplifier is the color reflects up onto my 6550 tubes, .......
247: Tube DIY Asylum, Feebdack: use or not use. noises and adaptation advice (0.00)
Posted by PeterI on 2014-02-15, 10:58:59 (184.96.178.156)
On my new amplifier, there is a simple feedback network of 100pf 27Kohm R to the 8 ohm speaker tap, the one I use (all done according to the schematic). I had a horrible sound when first using the amp .......
248: Tubes Asylum, RE: Regarding 6L6WGBs in place of EL34s... (0.00)
Posted by PeterI on 2014-02-13, 14:38:02 (174.29.68.138)
Thanks Mike. PP UL. I have 422V on the plates, and each tube (currently EL34s) is at 43mA (individually adjustable with bias pot). I have 6P3S-E s to try also. Will increase the impedence on OPT by us .......
249: Tubes Asylum, Regarding 6L6WGBs in place of EL34s... (0.00)
Posted by PeterI on 2014-02-13, 10:08:06 (174.29.68.138)
Also don't mean to hijack this thread. I want to try old US TungSol 5881s (also labelled 6L6WGB) in my EL34 amplifier with 4.2K OPTs, but worried about possible incompatibility. I know I can put a mor .......
250: Tube DIY Asylum, RE: New Amp complete (won't be to everyone's taste but...) picture (0.00)
Posted by PeterI on 2014-02-07, 04:06:00 (174.16.208.64)
Thank you. see my post a couple down for picture. I'm not particularly proud of the underside, but it works ok. I fit a lot of pieces. Pete .......
251: Tube DIY Asylum, like to see the inside - picture (0.00)
Posted by PeterI on 2014-02-06, 13:41:21 (174.16.208.64)
Thank you. here's an underneath shot. No 90 degree bends on this wiring - all "shortest length" point-to-poin t (in most cases). Very rigid steel and aluminum chassis. And heavy with all that big .......
252: Tube DIY Asylum, RE: New Amp complete (won't be to everyone's taste but...) picture (0.00)
Posted by PeterI on 2014-02-06, 07:27:24 (174.16.208.64)
Thanks very much. Yes, it's Rustoleum's better (so-called "Professional High-performance") paint. almost auto paint finish, and hard. Pete .......
253: Tube DIY Asylum, I always wonder if ... (0.00)
Posted by PeterI on 2014-02-06, 07:02:32 (174.16.208.64)
you should use those in both legs of the AC primary to the transformer. Or is one ok? I have done both. Pete .......
254: Tube DIY Asylum, Thanks, friends. nt (0.00)
Posted by PeterI on 2014-02-06, 06:59:45 (174.16.208.64)
nt .......
255: Tube DIY Asylum, ammeter (0.00)
Posted by PeterI on 2014-02-06, 06:59:14 (174.16.208.64)
I have the manual for the amp and the test points for OP tube current are right on top, next to each tube. I have it at 42 mA now for the EL34s. That's a good idea. wouldn't be as accurate as my Fluk .......
256: Tube DIY Asylum, RE: That looks great. (0.00)
Posted by PeterI on 2014-02-05, 21:06:37 (174.16.208.64)
Thanks. The milliamp meter isn't hooked up yet. Not sure where in the circuit to put it. Possibly a momentary switch. .......
257: Tube DIY Asylum, "Spark" - haha. Only a couple good shocks (0.00)
Posted by PeterI on 2014-02-05, 16:06:18 (174.16.208.64)
working on this one. Thanks for your remarks. cheers .......
258: Tube DIY Asylum, RE: Great minds.... (0.00)
Posted by PeterI on 2014-02-05, 16:04:56 (174.16.208.64)
That looks very cool. production? or kit? cheers .......
259: Tubes Asylum, Thanks, good advice. (0.00)
Posted by PeterI on 2014-02-05, 16:04:01 (174.16.208.64)
I dont need tons of power. just don't want to stress tubes, or my amp. cheers Peter .......
260: Tubes Asylum, RE: vintage 6L6WGBs -Thanks (0.00)
Posted by PeterI on 2014-02-05, 15:19:44 (174.16.208.64)
Thank you - that is helpful. I can adjust current for each tube with a probe next to the tube, measured from 10ohm cathode resistor. (The amp was posted about today over on TubeDIY forum.) Pete ::: TO .......
261: Tube DIY Asylum, The original schematic. and some details. (0.00)
Posted by PeterI on 2014-02-05, 14:43:13 (174.16.208.64)
Input 6922 phase-splitters 6SN7 OP: EL34, but the reason I picked this design is because it is supposed to be easily adapted to KT88/6550. Possibly 6P3S-E. PS: 320-0 > schottky bridge > 220uf > cho .......
262: Tube DIY Asylum, RE: Where's the Power Tranny? (0.00)
Posted by PeterI on 2014-02-05, 12:08:15 (174.16.208.64)
PT is down front. actually 3 trannies: toroidal power, big filament tranny, and small one for bias over to the side. The black piece on top front is a vent (I call it the "codpiece"). Thanks! ::: TOPI .......
263: Tubes Asylum, vintage 6L6WGBs - what to run them at? (0.00)
Posted by PeterI on 2014-02-05, 11:19:12 (174.16.208.64)
I have a bunch of old (used) Tung-Sol 6L6WGB, also labelled 5881. They test ok. For my PP amp, what bias should these run at? I can adjust each OP tube individually. TDSL says -37V. What will the mA .......
264: Tube DIY Asylum, New Amp complete (won't be to everyone's taste but...) picture (0.00)
Posted by PeterI on 2014-02-05, 09:35:32 (174.16.208.64)
This is my new amplifier, built to clone the diyaudio "Ella" amplifier. Right now it has EL34s in it- sounding very powerful and authoritative. I'm hearing great sound - still running in, so to .......
265: Tube DIY Asylum, Thanks NT (0.00)
Posted by PeterI on 2014-01-31, 12:05:04 (174.16.208.64)
nt .......
266: Tube DIY Asylum, Funny you mention Moebius. i tried that... (pic) (0.00)
Posted by PeterI on 2014-01-31, 11:48:58 (174.16.208.64)
It was one of the first things I built from scratch, in mid-2012. Unfortunately it was not a big success, for several reasons. 1) I used mainly parts I had sitting around. 2) I tried to jam it int .......
267: Tube DIY Asylum, RE: Found it. RCA pre. Thanks (0.00)
Posted by PeterI on 2014-01-31, 06:58:45 (174.16.208.64)
Yes, this is very do-able. I don't want it to become my life's work; DIY audio is one of my many hobbies. I'd rather build and use. But always glad to learn. I'm mainly building because I have a surpl .......
268: Tube DIY Asylum, RE: Here's my 26 circuit with LL1660 -Thx (0.00)
Posted by PeterI on 2014-01-31, 06:53:18 (174.16.208.64)
Thanks for posting, that looks very interesting. I did see the Bartola site but much info there is way outta my league (meaning: above my technical level). Source of parts is a question. Where to get .......
269: Tube DIY Asylum, Found it. RCA pre (picture) Thanks 6CG7? 12BH7? (0.00)
Posted by PeterI on 2014-01-30, 19:00:15 (174.16.208.64)
Two-stage input amplifier 19-18, from 1952 RCA tube manual. Cool. Do you think 12BH7 would work as well? What about 6CG7? (6V heater). The vintage idea appeals to me. And sure wouldn't be a big in .......
270: Tube DIY Asylum, What do you think of this preamp design? (picture) (0.00)
Posted by PeterI on 2014-01-30, 13:36:05 (174.16.208.64)
Shows audio circuit only, PS on another page. I assume the 6SN7 serves both channels? 2 stages here, and less concern with filament voltage, though 6.3V supply is DC and beefy. Credit to B. Berma .......
271: Tube DIY Asylum, RE: Want to copy a simple vintage preamp circuit. which... (0.00)
Posted by PeterI on 2014-01-30, 10:57:54 (174.16.208.64)
Yes, should have known that about the shared cathode and filament voltage. Looks like you have to order the Coleman regulator kit from the UK. Thx .......
272: Tube DIY Asylum, RE: Want to copy a simple vintage preamp circuit. which... (0.00)
Posted by PeterI on 2014-01-30, 10:42:29 (174.16.208.64)
Thanks - those look great. I have a bagfull of 76s. Exotic stuff like Tango transformers is right away a no-no, but otherwise those can be done on a budget. will study the schematics. Thx ::: TOPIC:: .......
273: Tube DIY Asylum, RE: Want to copy a simple vintage preamp circuit. which... (0.00)
Posted by PeterI on 2014-01-30, 10:24:53 (174.16.208.64)
That looks cool as hell, and probably very do-able for me. I have 0D3s. I didn't know 26s could run 5V filamant, but I know those old tubes pull tons of amperage. Once, I would have had NO interest in .......
274: Tube DIY Asylum, RE: Want to copy a simple vintage preamp circuit. which... (0.00)
Posted by PeterI on 2014-01-30, 10:02:46 (174.16.208.64)
I was thinking a simplified version of (for example) Eico HF-85 (except no phono) which I've owned 2 of in the past. Yes, don't need a lot of gain. .......
275: Tube DIY Asylum, Want to copy a simple vintage preamp circuit. which... (0.00)
Posted by PeterI on 2014-01-30, 08:36:15 (174.16.208.64)
What would be a good simple tube preamplifier circuit to replicate with point to point wiring? I have lots of tubes: 12AX7, 12BH7, 6CG7, 6DJ8, 6SN7, 6SL7, EF86, 26, 71A, more. Have transformers, choke .......
276: Tube DIY Asylum, Has the dust settled yet? :) (0.00)
Posted by PeterI on 2014-01-28, 08:04:14 (174.16.208.64)
Looks like there's never a consensus here. That's ok. Being in the arts I am accustomed to relativity and open-ended questions. However, thanks for suggestions; it's an education. cheers .......
277: Tube DIY Asylum, Another amplifier I built had none (0.00)
Posted by PeterI on 2014-01-27, 09:37:38 (174.16.208.64)
No grid stoppers. It was the EL34 Music Machine (so-called Poindexter design). No resistors in series w/ grid on either inputs (6GK5s) or the OP tubes. No problems there. Pete .......
278: Tube DIY Asylum, Understood. and thanks to all for input. (0.00)
Posted by PeterI on 2014-01-25, 11:00:27 (174.16.208.64)
Physical size is the real problem. Peter .......
279: Tube DIY Asylum, As with my project, I see... (0.00)
Posted by PeterI on 2014-01-25, 10:26:18 (174.16.208.64)
I see your's is a combination of vintage and new. Thanks for posting chassis pics. Cheers .......
280: Tube DIY Asylum, Input 1K resistors - which is best? (0.00)
Posted by PeterI on 2014-01-24, 16:39:04 (174.16.208.64)
I don't normally sweat this sort of thing, but as my amplifier building skills improve sharply, I start to be more concerned with quality parts. Both the input tubes (6922 in SRPP) and the power tube .......
281: Tube DIY Asylum, That's great. She'll remember that, and will want to again. NT (0.00)
Posted by PeterI on 2014-01-24, 12:01:49 (174.16.208.64)
nt .......
282: Tube DIY Asylum, Bathtub capacitors - any good for signal coupling? (0.00)
Posted by PeterI on 2014-01-23, 07:21:45 (71.218.145.151)
I have a bunch of old bathtub capacitors that I salvaged from some vintage gear recently. I measured them and nearly all are within spec. (Of course, I don't know if they leak DC yet.) Are these consi .......
283: Tubes Asylum, Ha. Holiday in Europe sounds V good. NT (0.00)
Posted by PeterI on 2014-01-20, 16:26:28 (174.29.182.210)
and yes, listen to the music. :) .......
284: Tubes Asylum, RE: Are these rca 12au7a cleartops? (0.00)
Posted by PeterI on 2014-01-20, 12:53:47 (174.29.182.210)
Those cleartops may be very thoroughly tested, maybe with a fancy tester, more thorough than mine. They are good tubes, and that is probably just the market value in your country. I have lots of extra .......
285: Tubes Asylum, RE: Are these rca 12au7a cleartops? (0.00)
Posted by PeterI on 2014-01-20, 12:30:57 (174.29.182.210)
Yes, they are. They are as common as water over here in N. America. Not a bad tube if you like 12AU7's. What are they, US$5 apiece? Not a big risk on your part. I wouldn't pay much more. Orange pri .......
286: Tube DIY Asylum, The "Knolling" school of restoration. (0.00)
Posted by PeterI on 2014-01-12, 10:57:43 (75.166.179.190)
Very "rectilinear". Obviously well thought-out and executed. I'm not so anal but I could learn from this. .......
287: DIY HiFi Forum, Question about Ella bias supply - 22K pots (0.00)
Posted by PeterI on 2014-01-11, 16:07:40 (174.29.180.38)
This a pretty specialized and isolated question. I am looking at the schematic for Ella 3.7. In the bias supply -50VAC is rectified and filtered and sent to 4x 22K pots for output tubes. Does each pot .......
288: Tubes Asylum, Thanks for input. (0.00)
Posted by PeterI on 2014-01-10, 08:41:48 (174.29.29.208)
No brand name, just a big M inside a gear shape. I'll put them up for sale - maybe someone will have a use for them. happy new year .......
289: Tubes Asylum, 8pin octal to 9pin adapter - what are these? pics (0.00)
Posted by PeterI on 2014-01-09, 16:17:58 (174.29.29.208)
I have a few of these adapters to put a 12AT7 into an octal socket. Got them in a lot buy. They even have a pot to adjust voltage. What 8 pin tube would they replace, 6 or 12SN7? Not sure what .......
290: Tube DIY Asylum, This is it, right? (link) (0.00)
Posted by PeterI on 2013-12-30, 07:39:00 (174.29.29.208)
Same board, different HK source? I've looked at this as well. I sometimes regret selling my Hagerman Cornet tube Phono preamp. I have a pretty good power supply already for that circuit. Pete ::: TOPI .......
291: Vintage Asylum, RE: you had that right. nt (0.00)
Posted by PeterI on 2013-12-25, 15:06:43 (174.29.29.208)
nt .......
292: Tube DIY Asylum, RE: What this country needs is a good 3-5Hy choke... (0.00)
Posted by PeterI on 2013-12-25, 15:01:30 (174.29.29.208)
Your first post here, trobbins? I am honored. That seems promising and useful but I'm not sure if those parts are available in North America and also may not be practical for other than bench work due .......
293: Vintage Asylum, Thanks for advice, the problem appears to be (0.00)
Posted by PeterI on 2013-12-25, 14:39:19 (174.29.29.208)
an incompatability with my tube preamp. Unexplained other than that. The problem disappears when using: 1) music signal straight from source. 2) source thru DAC. 3) other SS preamp is used (Superphon .......
294: Vintage Asylum, $1099? Not in this lifetime, but ... (0.00)
Posted by PeterI on 2013-12-24, 07:59:25 (174.29.79.221)
I know about Van Alstine and wish I could adopt some of their mods. Excellent stuff and thx for the link. I'm not married to any of my gear; I'm a budget DIYer. cheers, and Merry Christmas, Happy Holi .......
295: Vintage Asylum, RE: Hafler DH-220 amp makes speakers pulse in and out. (0.00)
Posted by PeterI on 2013-12-23, 14:18:52 (174.29.79.221)
Thanks. Do subsonic signals cause this? I just set DC offset on both channels to near 0V. I can't seem to adjust bias on this amp, but I doubt that's the problem. It's still doing it. Filter caps wi .......
296: Vintage Asylum, Hafler DH-220 amp makes speakers pulse in and out. (0.00)
Posted by PeterI on 2013-12-23, 12:56:23 (174.29.79.221)
My vintage Hafler DH-220 SS amplifier exhibits something I have seen in the past but very rarely so I haven't had to solve it. The speakers (8ohm) push out and then pull in slowly, to the limits of th .......
297: Tube DIY Asylum, Thanks for input - helpful to others as well... (0.00)
Posted by PeterI on 2013-12-23, 12:18:06 (174.29.79.221)
I like Edcor. But I waited 6 weeks for my OPTs so not in hurry to do that again. Possibly Edcor would have chokes in stock. .......
298: Tube DIY Asylum, There it is, Thanks. NT (0.00)
Posted by PeterI on 2013-12-21, 20:44:57 (174.29.86.174)
nt .......
299: Tube DIY Asylum, RE: What this country needs is a good 3-5Hy choke... (0.00)
Posted by PeterI on 2013-12-21, 15:58:02 (174.29.86.174)
Thanks for tip and source. Nice low DCR. I guess I'll sell (some of) my collection - How the hobby supports itself, right? cheers MC and HNY .......
300: Tube DIY Asylum, Agreed. I need vintage US iron. (0.00)
Posted by PeterI on 2013-12-21, 15:54:43 (174.29.86.174)
The chokes for old Dynaco amps are closer. .......
301: Tube DIY Asylum, My pile of chokes (picture) (0.00)
Posted by PeterI on 2013-12-21, 15:21:51 (174.29.86.174)
Many decent ones but nothing that meets the criteria. (7 of the 9) .......
302: Tube DIY Asylum, 4 ohm tap. (0.00)
Posted by PeterI on 2013-12-21, 15:16:10 (174.29.86.174)
Yes, my OPTs have 4 ohm tap. I'd forgotten until recently about the doubling. So i could put 8 ohm speakers on 4 ohm spkr tap for 8.4Kohm. Thanks for reminder. .......
303: Tube DIY Asylum, What this country needs is a good 3-5Hy choke... (0.00)
Posted by PeterI on 2013-12-21, 14:44:26 (174.29.86.174)
one that can handle 300mA, isn't too big, and under $30! any sources? - i'm searched out. Peter .......
304: Tube DIY Asylum, RE: Mullard mustard caps -? (0.00)
Posted by PeterI on 2013-12-21, 11:14:36 (174.29.86.174)
Not to change the subject, but how do Philips Mullard 'mustard' caps stack up? I have several 0.1uf 400V. I know the guitar guys like them, but for the tone section of my Eico HF81? Thanks Peter ::: T .......
305: Tubes Asylum, OK thanks. i will give them a good thorough run NT (0.00)
Posted by PeterI on 2013-12-21, 09:56:04 (174.29.86.174)
nt .......
306: Tube DIY Asylum, RE: PS voltage calculations - (EH Scott picture) (0.00)
Posted by PeterI on 2013-12-21, 06:36:08 (174.29.86.174)
Yes, you're right about 6L6. I should have known that with my experience with Heathkit W5Ms which have 9K OP transformer. I used 6P3S-E then (2 yrs ago). On the other hand, my (old but good TS) 6L6 .......
307: Tube DIY Asylum, RE: PS voltage calculations - (0.00)
Posted by PeterI on 2013-12-20, 20:06:38 (174.29.86.174)
Would be class AB. I'd hope to get 20 watts+ from a PP pair of 6L6WGB UL. 40watts + from a pair of 6550. I have nice old US Tung-Sols. I have been looking at the so-called "Ella'' design (sometimes di .......
308: Tubes Asylum, RE: Are these Shuggie EL34s supposed to be any good? (picture) (0.00)
Posted by PeterI on 2013-12-20, 15:41:20 (174.29.86.174)
Thx. They sound OK, been using in Triode mode. Trying to compare with older GE 6CA7 fat bottles. nothing conclusive decided yet. best to you in the Holidays, Mike .......
309: Tube DIY Asylum, RE: PS voltage calculations -Thanks... also. (0.00)
Posted by PeterI on 2013-12-20, 15:38:22 (174.29.86.174)
Thanks very much. The input of the experienced is highly valued. I am seeing some DIY amplifier designs for EL34, but claim that 6L6GC and even 6550 OP tubes can be used (just with lower plate voltag .......
310: Tube DIY Asylum, PS voltage calculations - a question (0.00)
Posted by PeterI on 2013-12-20, 12:32:46 (174.29.86.174)
My power chain goes like this: PT 315-0-315 > fullwave diode bridge > 22ouf 500V > 5H choke > 220uf > B+ then 5000ohm R. I plan to use PP EL34 and Edcor 4.2K 50W OPTs. What can I expect my B+ to be ? .......
311: Tubes Asylum, Are these Shuggie EL34s supposed to be any good? (picture) (0.00)
Posted by PeterI on 2013-12-20, 12:07:21 (174.29.86.174)
I got these 4 Chinese EL34s as NOS, sorta cheaply. I only have a few hours on them. Was using in a new amp so the amp itself was still settling in. They don't look like some other Chinese EL34 tube .......
312: Speaker Asylum, RE: Why not contact VIfa? (0.00)
Posted by PeterI on 2013-12-19, 11:55:36 (174.29.86.174)
Vifa doesnt exist as a separate entity. Their European website, Tymphany, isn't helpful to the DIYer. Madisound has the replacement rubber surrounds. cheers .......
313: Speaker Asylum, Thanks for tip. (0.00)
Posted by PeterI on 2013-12-19, 09:26:03 (174.29.86.174)
I may do the surrounds myself since finding Madisound sells them, (though not shown in their online catalog). I've done surrounds before. They had stiffened to the point that the rubber didnt spring .......
314: Tube DIY Asylum, RE: TO-220's are a bitch!! (0.00)
Posted by PeterI on 2013-12-19, 07:59:35 (174.29.86.174)
That makes sense. I sometimes use turret boards but not with these diodes. Thx .......
315: Tube DIY Asylum, Thanks to responders. helpful... (pic) (0.00)
Posted by PeterI on 2013-12-19, 07:58:05 (174.29.86.174)
So it's normal to let the top tabs hang in the air on the TO-220 type diode. "Not the most elegant but works" describes all my work! Thanks. :) I am working on "elegant" in the new projects. This .......
316: Vintage Asylum, You schooled that young man. (0.00)
Posted by PeterI on 2013-12-19, 07:25:20 (174.29.86.174)
Because I sell locally and used to help run our Denver 'Vintage Voltage Expo', I have turned on a number of young people to vintage electronics. I know what you mean. Cheers Pete .......
317: Tube DIY Asylum, RE: Does anyone have a picture of their Schottky diode bridge? (0.00)
Posted by PeterI on 2013-12-18, 07:26:13 (174.29.86.174)
Thanks but I don't mean schematic, I mean actual physical placement, on perf board? terminal strips? .......
318: Tube DIY Asylum, Does anyone have a picture of their Schottky diode bridge? (0.00)
Posted by PeterI on 2013-12-17, 21:15:25 (174.29.86.174)
or a bridge made from Schottkys and UF4007 combo? Cree w/ TO-220 case. I'm not not sure how to physically mount these, tho I have polarities correct. Maybe someone can show a clever method? (I don't w .......
319: Speaker Asylum, Thanks very much. nt (0.00)
Posted by PeterI on 2013-12-16, 08:06:10 (174.29.86.174)
nt .......
320: Speaker Asylum, The question isn't about Thiel, it's about (0.00)
Posted by PeterI on 2013-12-15, 13:19:13 (71.218.158.125)
This is not the first time people have seen the hardening of butyl rubber surrounds. It's about rubber surrounds in general, not just Thiel. I can contact Thiel anytime. Their customer service is exc .......
321: Speaker Asylum, RE: Woofer surrounds, Thiel CS 1.2 (0.00)
Posted by PeterI on 2013-12-15, 07:00:43 (184.96.183.150)
you know, that's a thought. Would need repeated treatments probably. I handle a lot of speaker drivers, in and out of cabinets, so i know what the rubber normally looks like, and these have clearly be .......
322: Speaker Asylum, Woofer surrounds, Thiel CS 1.2 (0.00)
Posted by PeterI on 2013-12-14, 16:55:42 (71.218.159.197)
My older Thiel 1.2 speakers have Vifa P17 WJ woofers with butyl surrounds. The rubber seems to have stiffened in recent years, maybe age or environmental conditions, but they don't seem supple as they .......
323: Tube DIY Asylum, RE: Calculator for PT draw (0.00)
Posted by PeterI on 2013-12-12, 08:16:08 (174.29.2.94)
Useful, very simple - maybe overly so? Is it accurate? .......
324: Digital Drive, Thanks nt (0.00)
Posted by PeterI on 2013-12-11, 02:27:41 (174.29.2.94)
nt .......
325: Digital Drive, RE: Cheap optical to spdif converter Thanks (0.00)
Posted by PeterI on 2013-12-10, 14:40:49 (174.29.2.94)
Thanks for the tip. Is USB going to stream digital to my DAC better than optical (toslink)? or about the same? Pete .......
326: Speaker Asylum, I've been looking at the Zaph SR 71... (0.00)
Posted by PeterI on 2013-12-09, 14:04:02 (174.29.2.94)
A do-able project for me, but they are 85db efficient. Have you found them to need a lot of power to sound as they should? Pete .......
327: Digital Drive, Cheap optical to spdif converter - what to replace it? (picture) (0.00)
Posted by PeterI on 2013-12-09, 07:54:03 (174.29.2.94)
I use a Nixon Tube DAC (coax input only) connected to my MacBook's (dedicated music 'server') optical out jack for music. Signal passes through this cheap converter, for optical to digital coax. Ob .......
328: Tube DIY Asylum, RE: I tried it. Sounds good. NT (0.00)
Posted by PeterI on 2013-12-08, 07:09:55 (174.29.2.94)
Voltages about the same tho. .......
329: Tube DIY Asylum, RE: empiric test (0.00)
Posted by PeterI on 2013-12-07, 20:04:37 (174.29.2.94)
Thank you, a good suggestion. But the 6N1P tubes are still in the mail to me, a week late. I finished the amp early and I'm too impatient. I'll get this ironed out. .......
330: Tube DIY Asylum, I know they are different (0.00)
Posted by PeterI on 2013-12-07, 06:42:59 (174.29.2.94)
But I was under the impression that i could use 6DJ8 for the time being, and that it would 'sound' better. Wrong perhaps. .......
331: Tube DIY Asylum, RE: 6CG7 (0.00)
Posted by PeterI on 2013-12-07, 06:41:07 (174.29.2.94)
Thanks. Are you saying 6CG7 is a plug-in replacement in this circuit? or I would alter the circuit to accommodate 6CG7? Pete .......
332: Tube DIY Asylum, Yes. and a picture for anyone interested .... (0.00)
Posted by PeterI on 2013-12-06, 12:32:21 (174.29.2.94)
Going for a vintage look. Like an old British car (MG, etc) - dark red and black with plated metal touches. Chassis, all 3 transformers and choke vintage used. Thanks to Jef Larson for circuit. Pe .......
333: Tube DIY Asylum, A little harsh right now - needs break-in ? (0.00)
Posted by PeterI on 2013-12-06, 11:59:39 (174.29.2.94)
Overall, quality is there. As expected from 6V6. Sound is titled to treble and a bit grainy for now. Russian PIO caps, etc maybe need to run-in for several... a. hours b. days. found a pair NOS 1962 .......
334: Tube DIY Asylum, RE: Voltages off - some advice? Thanks... (0.00)
Posted by PeterI on 2013-12-06, 08:42:25 (174.29.2.94)
Thanks for that helpful response. I know some of that math, but not nearly enough. I don't want to change resistors haphazardly - but I may tweak a little, so your suggestion helps. I wonder if 6N1P a .......
335: Tube DIY Asylum, Voltages off - some advice? (0.00)
Posted by PeterI on 2013-12-06, 04:30:10 (174.29.2.94)
I finished building this 6V6 amplifier and it's working well. My only concern is the voltages to the coupling caps. I followed the schematic closely and most voltages are within 5%. There 'should' .......
336: Vintage Asylum, I'm doing this as well, sort of ... (0.00)
Posted by PeterI on 2013-11-24, 12:17:42 (174.29.2.94)
Building MDF cabinets for classic (read: antique) Seas 25 TV EW woofer, and new Seas 27 TDFC tweeter. Hope to see pics of your's. cheers Pete .......
337: Speaker Asylum, RE: If you haven't seen this yet... (0.00)
Posted by PeterI on 2013-11-22, 10:17:36 (71.33.207.171)
Thanks, that's useful. (I've seen the expensive new A25 kit many times.) The technical specs don't mention (somewhat perversely) the crossover point of that kit speaker. Clearly, the xover is much hi .......
338: Tube DIY Asylum, Thanks. NT (0.00)
Posted by PeterI on 2013-11-21, 12:18:27 (71.33.206.54)
nt .......
339: Tube DIY Asylum, May I ask about your preamp? (0.00)
Posted by PeterI on 2013-11-21, 08:43:10 (184.96.173.166)
I have more 71As, 26s, and 80s than I know what to do with. Is a 71A preamp difficult to build, or expensive? do you have a link to a DHT preamp design? Thanks, not trying to hijack this thread. cheer .......
340: Tube DIY Asylum, They are what Poindexter recommended... (pic) (0.00)
Posted by PeterI on 2013-11-21, 08:37:32 (184.96.173.166)
in his Music Machine amplifier, after many tests. And I dutifully used in my version, of MM with good results. Panasonic TS-HB and -ED (photo E Kingsbury) .......
341: Vintage Asylum, RE: McIntosh ad from 1950 $249! (0.00)
Posted by PeterI on 2013-11-21, 07:27:21 (184.96.173.166)
That's very interesting, the ad copy reads like an engineering tract. And $249 dollars was a LOT (LOT!) of money then. Must have been commercial applications. .......
342: Speaker Asylum, Thanks (0.00)
Posted by PeterI on 2013-11-20, 14:42:59 (184.96.173.166)
but I shouldn't have said "scientific". What I meant was "experience- and fact-based". Obviously, this is meant to be a simple project. cheers .......
343: Speaker Asylum, Thanks for info. Going for a Dyn A25 'clone' (0.00)
Posted by PeterI on 2013-11-20, 12:49:56 (184.96.173.166)
The Fs of this tweeter is 550 and I'll be crossing at ~1800hz. I *might* be asking a little too much of the tweeter, but we'll see how it works. cheers .......
344: Vintage Asylum, RE: I have the amplifier and tuner out of one of the 16A (0.00)
Posted by PeterI on 2013-11-19, 14:36:33 (184.96.173.166)
actually I have the similar (and rarer) 16A. .......
345: Speaker Asylum, question about calculating my speaker crossover (0.00)
Posted by PeterI on 2013-11-19, 12:20:24 (184.96.173.166)
I am trying to build a simple speaker using some parts I have on hand. Would appreciate some advice. Speaker must be around 8ohm, for my amp. Ported 2 way, simple 1st order crossover. Vintage Seas woo .......
346: Tube DIY Asylum, Thanks for tip. I ordered one to use on new project. NT (0.00)
Posted by PeterI on 2013-11-16, 13:56:14 (174.16.192.62)
nt .......
347: Vintage Asylum, That's a lotta tubage (0.00)
Posted by PeterI on 2013-11-16, 13:47:00 (174.16.192.62)
10 tubes! I'm guessing 4 for Phono and 6 in the line stage? 3 stages of gain? .......
348: Tube DIY Asylum, Thanks- that's exactly what they are ... (0.00)
Posted by PeterI on 2013-11-15, 12:27:01 (174.16.192.62)
Once I had a name, they were easy to research. Very hi quality German Rs, made 1960s. But still not sure if carbon film or metal film? (not that it will make a big difference. I plan to use them regar .......
349: Tube DIY Asylum, Vintage resistor question - picture (0.00)
Posted by PeterI on 2013-11-15, 08:05:22 (174.16.192.62)
I am always harvesting old electronic gear for parts and I found a very hi-Q testing unit with these resistors. Also got many mustard capacitors from the unit (0.1uf 400v). Pictured is a 2W resisto .......
350: Tube DIY Asylum, Where can you get a 320V power tranny? (0.00)
Posted by PeterI on 2013-11-13, 18:54:42 (204.132.219.18)
Is Antek the only way to go? 0-320V or 160-0-160 VAC is what I am looking for. Edcor takes so long if not in stock (it isn't). I'd need 200mA + I have many vintage pwr transformers but all very HV. W .......
351: Tube DIY Asylum, Thanks NT (0.00)
Posted by PeterI on 2013-11-12, 15:04:46 (71.33.199.41)
nt .......
352: Tube DIY Asylum, RE: Trying to figure out the layout of this 6V6 amp. Thanks (0.00)
Posted by PeterI on 2013-11-12, 14:03:26 (71.33.199.41)
Excellent advice, thanks. I was planning to tuck choke underneath but that will certainly help. Side wall it is. This large beefy Stancor choke 10H, may not be rated high enough @ 110mA - the amp may .......
353: Tube DIY Asylum, Trying to figure out the layout of this amp. Picture (0.00)
Posted by PeterI on 2013-11-12, 12:54:57 (71.33.199.41)
Proposed placement of the major elements for 6V6 amplifier. Octal OP tubes are fixed there because of holes underneath (not shown). Many of these parts will be mounted under top. Peter ::: TOPIC: .......
354: Tube DIY Asylum, Thanks. NT (0.00)
Posted by PeterI on 2013-11-12, 07:04:05 (71.33.199.41)
nt .......
355: Tube DIY Asylum, Very droll, you Americans. cheers, Mike. nT (0.00)
Posted by PeterI on 2013-11-12, 07:03:26 (71.33.199.41)
nt .......
356: Tube DIY Asylum, This is the pot? link (0.00)
Posted by PeterI on 2013-11-11, 13:45:01 (71.33.199.41)
Those look ok, and at $26 are worth a try. I am tired of using crappy fake Alps, with their lousy leads. The best I used before was a good Noble black box Pot that I pulled out a of a fancy Pioneer r .......
357: Tube DIY Asylum, RE: What Vol control pots - Goldpoint (0.00)
Posted by PeterI on 2013-11-11, 13:34:46 (71.33.199.41)
Those look well-made. $159 a little steep, but if it makes as much sonic difference as OPTs then I suppose worth the investment. Thanks for tip. .......
358: Tube DIY Asylum, What Vol control pots are people using on their DIY amplifiers? (0.00)
Posted by PeterI on 2013-11-11, 11:44:06 (71.33.199.41)
I am looking for (reasonably priced) Volume pots for my 2 amp projects. What types and brands of input potentiometers are people using and what suppliers? resistor-type? Alps? I am looking at the 50Ko .......
359: Vintage Asylum, I have the amplifier and tuner out of one of those 800s (0.00)
Posted by PeterI on 2013-11-05, 14:35:06 (71.33.199.41)
The Scott 800B amplifier - 6L6 mono (obviously), preamplifier/tuner combo - actually WORK - unrestored from 1948. The power transformer is the largest I've ever seen - 7" high. I don't know what to .......
360: Vintage Asylum, RE: Sam Kim Fisher 500 (0.00)
Posted by PeterI on 2013-11-05, 11:06:20 (75.166.178.125)
I had a Fisher 500 receiver (shipped from original purchaser in Canada) that was lightly upgraded and restored by Mr Kim. Sounded fantastic. .......
361: Tube DIY Asylum, RE: Little-known Hewlett Packard "Red Series' tube preamp -PCB (0.00)
Posted by PeterI on 2013-11-01, 11:50:41 (174.29.179.168)
Thanks for input Mike. Now that it is together and functioning, I can make some small improvements, such as caps. B+ specified is 260VDC. The PS is 200VAC (.01uf cap across) > UF4007 bridge > 56uf .......
362: Vintage Asylum, RE: Heathkit W-6m (0.00)
Posted by PeterI on 2013-11-01, 10:31:21 (174.29.179.168)
I would love those. but a lot of tubes for a monoblock! And a voltage doubler PS, no less. .......
363: Tube DIY Asylum, RE: Nice! Thx (0.00)
Posted by PeterI on 2013-10-31, 13:58:12 (174.29.179.168)
The premade circuit board is a Hong Kong item, purported to be a clone of the Marantz 7C. Uses 2-12AX7, then 2-12AU7. I am using 12BH7 in place of the latter. 2 selectable inputs, 2 pair of output ja .......
364: Tube DIY Asylum, Little-known Hewlett Packard "Red Series' tube preamp (pictures) (0.00)
Posted by PeterI on 2013-10-31, 13:25:45 (174.29.179.168)
Ok, I'm kidding about that. This is my newly built preamp, using old H-P chassis and enclosure. It's working very well. B+ voltage a hair lower than I'd like. All the new capacitors seem a bit h .......
365: Vintage Asylum, RE: What tweeter? (0.00)
Posted by PeterI on 2013-10-31, 07:32:50 (174.29.179.168)
Seas 19TNF /C H553. I can't find specs on them, yet. If like other 19TNF, they will only go down to 4khz. Yes, if they aren't right, will be looking for Hi-Q tweeters that will go down to 2kHz. or j .......
366: Vintage Asylum, Here's a design I'm gathering part for ... 6V6 (0.00)
Posted by PeterI on 2013-10-30, 12:39:01 (174.29.179.168)
Jef Larson's "Abraxas" 6V6 PP amplifier. -not sure if this is a copyrighted design (doesn't say so). This is really for the DIY tube board. Pete .......
367: Vintage Asylum, RE: Sounds like a plan - thx, good advice (0.00)
Posted by PeterI on 2013-10-30, 12:35:27 (174.29.179.168)
I am thinking I'll need to use a 8uf cap to get the tweeter to reach down to 2000 hz. And that may be asking too much of this tweeter on hand. Pete .......
368: Vintage Asylum, Thanks airtime NT (0.00)
Posted by PeterI on 2013-10-29, 15:16:33 (174.29.179.168)
nt .......
369: Vintage Asylum, Thanks Mark. -NT (0.00)
Posted by PeterI on 2013-10-29, 15:15:05 (174.29.179.168)
nt .......
370: Vintage Asylum, Thanks to all responders, but (0.00)
Posted by PeterI on 2013-10-29, 14:07:58 (174.29.179.168)
I have all the parts including many caps. Just needed to know about where the old, original woofer (which I am using) rolled off. Looks like it's around 1600Hz, lower than I thought. I'm not buying ne .......
371: Vintage Asylum, Anyone know the rolloff of a Dynaco A25 woofer? (0.00)
Posted by PeterI on 2013-10-29, 07:41:48 (174.29.179.168)
I am planning to build simple A25 "clones" and a little research found no hard info on this. I am using original Seas 25 TV EW woofers, and modern Seas tweeters. A guess would be the tweeter should co .......
372: Tube DIY Asylum, RE: Chassis layout for 6V6 amp - another chassis for preamp (0.00)
Posted by PeterI on 2013-10-23, 09:23:41 (174.16.200.191)
Hey, that looks good. 2 switches - one for filaments, 2nd for B+? I have used that oak from Lowe's. When I built my Music Machine clone last year, i had 2 pieces of metal so i split the amp in 2 - .......
373: Tube DIY Asylum, RE: Chassis layout for 6V6 amp (3rd picture) (0.00)
Posted by PeterI on 2013-10-22, 15:42:41 (174.16.200.191)
Thanks for that. I had a feeling I should keep big iron away from signal input, which is why I attempted a a rearrangement of the furniture for the 2nd picture. I will apply your suggestions but m .......
374: Tube DIY Asylum, RE: Chassis layout for 6V6 amp (2nd picture) (0.00)
Posted by PeterI on 2013-10-22, 08:44:24 (174.16.200.191)
Thanks for input. It was a big tester "Audio level Indicator for RF square law detector". I am not making this up, (was for RF broadcasting 1950s). I do have the orig meter for the hole, a big dB m .......
375: Tube DIY Asylum, Chassis layout for 6V6 amp (picture) (0.00)
Posted by PeterI on 2013-10-22, 07:49:19 (174.16.200.191)
I am gathering parts for a 6V6 amplifier based on Jef Larson's "Abraxas" 6V6 amp, and I like to use vintage chassis. This is a large, thick, all aluminum base. Does anyone think there would be pro .......
376: Tube DIY Asylum, RE: current draw (0.00)
Posted by PeterI on 2013-10-22, 07:17:36 (174.16.200.191)
Thanks. I can see this PS is going to be overbuilt, but that's not a bad thing. .......
377: Tube DIY Asylum, current draw (0.00)
Posted by PeterI on 2013-10-22, 04:27:01 (174.16.200.191)
Not sure what my current draw will be for this preamp. I have some beefy chokes but don't want to use a 200mA choke in a PS that only draws 40mA. Pete .......
378: Tube DIY Asylum, RE: PS calculation for 260VDC (0.00)
Posted by PeterI on 2013-10-21, 13:18:21 (174.16.200.191)
Thanks for the parts tip. For now I'll probably use 4 UF4007 I have on hand. After the CLC, I'll use a 1-2 watt resistor to get the voltage close to 260VDC. The preamp is a premade board and has an a .......
379: Tube DIY Asylum, Thanks. Got it. NT (0.00)
Posted by PeterI on 2013-10-21, 11:32:07 (174.16.200.191)
nt .......
380: Tube DIY Asylum, PS calculation for 260VDC (0.00)
Posted by PeterI on 2013-10-21, 08:45:51 (174.16.200.191)
I have an opportunity to buy a good toroidal transformer with 200VAC output, not CT. I need 260VDC for a tubed preamp. I was planning to do CLC chain: full wave rectifier, 2 diodes > 56uf 400V cap > 4 .......
381: Tube DIY Asylum, Mullard (0.00)
Posted by PeterI on 2013-10-17, 19:17:14 (174.16.200.191)
That EF86 input appeals to me. And I have a few of those. I like vintage designs. .......
382: Tube DIY Asylum, Thanks. that's helpful. NT (0.00)
Posted by PeterI on 2013-10-17, 19:13:33 (174.16.200.191)
nt .......
383: Tube DIY Asylum, RE: One other thing: my power tranny.... (0.00)
Posted by PeterI on 2013-10-17, 14:59:40 (174.16.200.191)
Hmmm. well, I will have to look again. Thanks for tips. This is my source of knowledge for power supplies and calculating voltages in various rectifier schemes: .......
384: Tube DIY Asylum, choke in bias supply (0.00)
Posted by PeterI on 2013-10-17, 14:55:58 (174.16.200.191)
Thanks for the detailed response. Funny you should mention a Triad C-3X filter choke -- I have one on my desk as we 'speak'. In its original vintage box. That should make a stout bias supply. I'm visu .......
385: Tube DIY Asylum, One other thing: my power tranny.... (0.00)
Posted by PeterI on 2013-10-17, 12:21:57 (174.16.200.191)
one of my power transformers makes 288-0-288 VAC out (it's a monster so I am sure current is sufficient.) with full wave rectifier (2 diodes) CLC PS I should see a B+ of around 410VDC ? Pete ::: TOP .......
386: Tube DIY Asylum, How much amperage do you need for a bias supply ? (0.00)
Posted by PeterI on 2013-10-17, 11:46:49 (174.16.200.191)
I was planning to use a separate transformer for bias supply of -50V. What current capability does it need for 4 big OP tubes? only because I have no other tap for the bias supply. Pictured is a sm .......
387: Tube DIY Asylum, That's interesting. also, tubes. (0.00)
Posted by PeterI on 2013-10-17, 10:02:04 (174.16.200.191)
Thanks for schematic. Looking at the board (and the site) there wasn't much info, such as driver tubes and where B+ comes in. Can't beat the budget (HK?) price. I think I'd prefer to have point to poi .......
388: Tube DIY Asylum, RE: Funny, I used the Tubes4hifi board in my ST70 as well......... (0.00)
Posted by PeterI on 2013-10-17, 09:52:27 (174.16.200.191)
That's good. Triode would be a factor as well. Tubes4hifi is certainly a quality board. Looking back (2011), my listening conditions were less than ideal, but I was comparing with my HF81. cheers ::: .......
389: Tube DIY Asylum, RE: OPTs (0.00)
Posted by PeterI on 2013-10-17, 09:45:36 (174.16.200.191)
OPTs are 4.2Kohm, with taps of 4, 8, and 16 ohm. Thanks for input Peter .......
390: Tube DIY Asylum, RE: Schematic/design need for 6550/EL34 amplifier (0.00)
Posted by PeterI on 2013-10-17, 02:47:02 (71.218.138.194)
I used the tubes4hifi board when i had an ST-70. It was very well made, and everything went into place well, adjusted easily. Unfortunately, when done, the ST-70 sounded to me like a solid state ampli .......
391: Tube DIY Asylum, Thanks, that's great. (0.00)
Posted by PeterI on 2013-10-17, 02:40:15 (71.218.138.194)
Will study this. Thx Pete .......
392: Tube DIY Asylum, Schematic/design need for 6550/EL34 amplifier (0.00)
Posted by PeterI on 2013-10-16, 14:40:07 (174.16.215.108)
I'm nowhere near as experienced as most of the people here, but encouraged by the success of last year's amp build, I want to try something bigger, more powerful but still simple. I have good iron, po .......
393: Tube DIY Asylum, RE: Identifying Transformer wiring - colors (0.00)
Posted by PeterI on 2013-10-04, 13:34:07 (71.218.150.72)
Thanks for help. I was depending on wire color too much. better to measure. Pete .......
394: Tube DIY Asylum, Identifying Transformer wiring - colors (picture) (0.00)
Posted by PeterI on 2013-10-04, 09:53:43 (71.218.150.72)
I have an unusual old RCA potted transformer I picked up. It is potted, hi-quality, maybe from 1950s. A sticker on it said 300v. Normally, the wiring colors are straight forward but i can't figure .......
395: Tube DIY Asylum, How's this for a sturdy tube platform? (picture) (0.00)
Posted by PeterI on 2013-09-24, 12:00:12 (71.218.150.72)
Removed from 1950s test equipment. Solid machined thick steel base, 4 tube positions, suspended on rubber mounts. Even has ceramic terminal blocks on each side. Heavy metal. Pete .......
396: Tube DIY Asylum, RE: PP 6550/KT88 another tranny (0.00)
Posted by PeterI on 2013-09-12, 02:17:21 (71.218.150.72)
Thanks for info. I always try to go vintage first. Antek is pretty good and I should have thought of that - I used an Antek trans in last year's amp project. The low profile may even fit in this chass .......
397: Tube DIY Asylum, RE: PP 6550/KT88 another tranny (0.00)
Posted by PeterI on 2013-09-11, 10:29:19 (75.166.183.137)
Thanks for advice. I have several good power transformers. Here's a vintage Stancor, new in box, but only 90mA current capability. I have 2 others that are 700VAC CT: Triad (160mA) and General Rad .......
398: Tubes Asylum, RE: 6550 (0.00)
Posted by PeterI on 2013-09-11, 07:06:58 (174.16.199.27)
They test very high. Were never stressed with only 200V on plates. Peter .......
399: Tubes Asylum, RE: Substitute for 6AN8? Thx. Trannies (0.00)
Posted by PeterI on 2013-09-11, 07:05:09 (174.16.199.27)
The chassis has thick steel perforated top and bottom plates (not shown). I would build up on top with OPTs. Thanks for tip on Edcor. I don't really need 100W capability - wouldn't 5K impedence be be .......
400: Tubes Asylum, RE: Substitute for 6AN8? good idea (Picture) 6550 (0.00)
Posted by PeterI on 2013-09-10, 12:26:59 (174.29.9.200)
Thanks, that is an excellent idea. I used Triode's smaller SCA35-style OPTs for a recent amp project. Possibly I could drive these 6550s with an ST-70 board? Or use 2 Triode Dyn Mark III boards? P .......
401: Tubes Asylum, RE: Substitute for 6AN8? Thx. Pic (0.00)
Posted by PeterI on 2013-09-10, 12:22:15 (174.29.9.200)
Thanks for suggestions. I have several good vintage transformers. I would use SS rectification. But after that, I would need to use an existing driver board - i couldn't design or modify one. Pet .......
402: Tubes Asylum, Substitute for 6AN8? (0.00)
Posted by PeterI on 2013-09-10, 06:35:39 (174.16.196.152)
I dont see a substitute for 6AN8 tubes in the TDSL but I'll bet someone here has an idea. I am trying to make a KT88 amplifier, and plan to use premade circuit boards, such as Dynaco reproduction PCBs .......
403: Vintage Asylum, RE: Stromberg Carlson ASR-533 tube magic Rs (0.00)
Posted by PeterI on 2013-04-12, 08:42:02 (71.212.133.25)
Thanks for the tips, Michael. I did notice a couple out-of-spec resistors, just today. Pete .......
404: Vintage Asylum, Stromberg Carlson ASR-533 tube magic (picture) (0.00)
Posted by PeterI on 2013-04-11, 16:47:01 (71.212.133.25)
I'm pretty amazed by what I'm hearing from this old 1959/60 Stromberg Carlson amplifier. It's the console version of their ASR-333 EL84 amplifier. For once, I didn't screw with coupling caps or cir .......
405: General Asylum, Thanks for posting those pics, Abe. NT (0.00)
Posted by PeterI on 2013-03-10, 04:27:48 (184.96.212.62)
nt .......
406: General Asylum, For the Colorado crowd, The Vintage Voltage Expo... (0.00)
Posted by PeterI on 2013-02-20, 07:15:31 (184.96.212.92)
Yeah, I post this just about every year, it's a cool event, March 24, 2013. Link to info, and a video that gives an accurate view of the experience. now in its 7th year. (I don't help run it, just .......
407: Tube DIY Asylum, top-notch craftsmanship. nt (0.00)
Posted by PeterI on 2012-12-26, 05:21:29 (174.16.238.153)
nt .......
408: Tube DIY Asylum, One thing: my voltages are low. apparently... (pic) (0.00)
Posted by PeterI on 2012-12-20, 09:41:49 (174.16.238.203)
The B+ voltage is around 384VDC after diode bridge; should be 400+. All voltages downstream are a bit low. I am using the specified 300VAC AnTek tranny. Apparently Poinz put the 6.3VAC taps right i .......
409: Tube DIY Asylum, RE: Wide Chassis (0.00)
Posted by PeterI on 2012-12-18, 11:53:46 (174.16.238.203)
Thanks. Not a bad idea - I once had a Jim Nichols-built EL84 amplifier (built on Hammond chassis) that had switchable PS (sold it, regrettably, in the search for 'more power'). There's a big toroidal .......
410: Tube DIY Asylum, My version of Kingsbury's Music Machine - picture (0.00)
Posted by PeterI on 2012-12-18, 10:55:37 (174.16.238.203)
I'm not a frequent poster here on this forum but I lurk and get useful info, and inmates have made good suggestions for my project. This is the 90% finished EL34 Music Machine (design Eric Kingsbur .......
411: MagneQuest/Peerless Forum, RE: need OPTs for amp project - email sent, thx. nt (0.00)
Posted by PeterI on 2012-11-23, 12:58:56 (174.16.254.29)
nt .......
412: Tube DIY Asylum, I wonder how these Tomiko OPTs are ... (0.00)
Posted by PeterI on 2012-11-11, 06:41:27 (174.16.254.222)
Japanese Tomiko transformers from David Yee in BC Canada. Good specs. .......
413: Tube DIY Asylum, This the schematic for MM (0.00)
Posted by PeterI on 2012-11-10, 20:04:12 (174.16.254.222)
except using 6-8k OPT. Class AB1? .......
414: Tube DIY Asylum, thanks for input. Budget (0.00)
Posted by PeterI on 2012-11-10, 16:06:25 (174.16.254.222)
I would like to get a decent hi-Q used pair for $200 or less. looks like the Triode Dyn OPTs are about that new, but i was thinking someone might have some used Magnequest, or vintage Eicos, or even o .......
415: Tube DIY Asylum, OPTs needed for project amp, recommendations (0.00)
Posted by PeterI on 2012-11-09, 11:08:43 (174.16.137.121)
I realize this forum isn't for buying and selling but please contact me off-list of you have a spare pair of used output transformers to sell (old or newer) meeting the following criteria: push pull f .......
416: MagneQuest/Peerless Forum, need OPTs for amp project (0.00)
Posted by PeterI on 2012-11-09, 07:22:04 (174.16.144.231)
I realize this forum isn't for buying and selling but please contact me off-list of you have a pair of used output transformers (old or newer) meeting the following criteria: push pull for EL34s in tr .......
417: Vintage Asylum, I barely got $90 for my single Hk preamp pic NT (0.00)
Posted by PeterI on 2012-10-25, 07:33:57 (174.16.137.227)
nt .......
418: Vintage Asylum, Maybe i should hang into my Superphon preamp... (0.00)
Posted by PeterI on 2012-10-19, 20:18:47 (174.16.137.227)
The Revelation II. It's a good one besides. Pete .......
419: Tube DIY Asylum, Thank you for advice... (0.00)
Posted by PeterI on 2012-09-02, 08:16:18 (174.51.102.111)
It happens that filaments and bias power will come from a separate transformer that will switch on first (a vintage unit). Then B+ on its own transformer. Pete .......
420: Tube DIY Asylum, RE: 6BQ5......Agreed (0.00)
Posted by PeterI on 2012-09-02, 08:14:04 (174.51.102.111)
I've owned (and worked on) so many 6BQ5 amps I've lost count. Want to try something new and develop my (lacking) DIY skills. It's funny because this whole DIY amp-building interest came about after lo .......
421: Tube DIY Asylum, RE: Try this puppy.......... OPTs (0.00)
Posted by PeterI on 2012-09-02, 08:10:11 (174.51.102.111)
I've seen those Triode Dynaco clone OPTs and they look very good; I'm sure excellent quality and $105 ea (shipped) isn't horrible. Pete .......
422: Tube DIY Asylum, Thanks (0.00)
Posted by PeterI on 2012-09-01, 14:09:51 (174.51.102.111)
for the info. Maybe I should build the Poindexter Music Machine with the original triode-6V6. But it only makes 6 watts per, and I'm not sure that's enough for me, and the wide variety of music i list .......
423: Tube DIY Asylum, Can I put PP EL34s in triode on 8K OPT? (0.00)
Posted by PeterI on 2012-09-01, 09:01:59 (174.51.102.111)
I am in the process of gathering parts for a Music Machine EL34 triode strapped PP. I have some OPTs w/ 8K impedances and 4/8 ohm out. Expecting no more than 10-12W. I got the OPTs originally for a .......
424: Vintage Asylum, caused spit-take ! nt (0.00)
Posted by PeterI on 2012-07-25, 14:52:09 (174.51.102.111)
nt .......
425: Vintage Asylum, Frank Zappa and Dynaco -picture (0.00)
Posted by PeterI on 2012-07-20, 20:27:01 (174.51.102.111)
Here's a picture of the late Frank Zappa in a recording studio using a RtR and Dynaco ST-70 tube amp and PAS preamp. I'm not a huge fan of his but to me it's an interesting document of rock n roll .......
426: Vintage Asylum, RE: might you post a link to or info on your HF-85's "upgrades" (0.00)
Posted by PeterI on 2012-06-30, 17:48:46 (174.51.102.111)
If you want to "get rid" of the "basket case" HF85, please contact me off list. thanks. would fix and keep. I too had some hum in my last HF85, but in phono, very minor. I did the usual stuff: new e .......
427: Tubes Asylum, Thank you; are there affordable alternatives in those sizes? and 600V? NT (0.00)
Posted by PeterI on 2012-06-30, 17:15:57 (174.51.102.111)
nt .......
428: Vintage Asylum, RE: You are welcome for the info... HF85 etc (0.00)
Posted by PeterI on 2012-06-30, 17:12:59 (174.51.102.111)
I had so much gear go thru my hands in the years 2006-2010: 2 Eico HF85s, Mac C20, ARC SP-3a, 2 Citation 1s, Conrad Johnson PV-2 (the same one, twice), Quicksilver. The first HF85 I bought locally an .......
429: Vintage Asylum, Thank you for info... (0.00)
Posted by PeterI on 2012-06-30, 15:10:07 (174.51.102.111)
I'm trying to decide what preamp to use w/ my Heathkit W-5 tube amplifiers. Looking at AA classifieds. The Citation A is older than I thought. I used to have Citation 1. Very nice, but many features I .......
430: Tubes Asylum, bypass film caps (0.00)
Posted by PeterI on 2012-06-30, 07:56:35 (174.51.102.111)
yes, thanks for info. I've never really done the ~.1uf bypass caps on PS electrolytics. But companies like ARC put them in on their best tube preamps such as SP-3, in 2 stages. And I think they know a .......
431: Vintage Asylum, Citation A solid state preamp? quality? mods? (0.00)
Posted by PeterI on 2012-06-29, 13:53:30 (174.51.102.111)
I know the Citation A preamp (1970s) doesn't have the greatest reputation and is not highly sought-after, but can it be modified with some modern (hopefully: better) capacitors, Vol pot, etc. Has anyo .......
432: Tubes Asylum, RE: Which Mono Tube Amp?!?! W-4am (0.00)
Posted by PeterI on 2012-06-29, 13:42:05 (174.51.102.111)
Hi Duane, Contact me off-list, if you're looking for a good single Heath W-4AM. best, Peter .......
433: Tubes Asylum, RE: Heath monoblocks complete, sounding very good (picture) (0.00)
Posted by PeterI on 2012-06-28, 17:38:09 (174.51.102.111)
Socket already done. Funny that Mr Stokes doesn't mention the .1 bypass capacitors in his instructions. I figured maybe he backed off supporting their purpose. I can always add them; maybe for compari .......
434: Tubes Asylum, Yes, will look for better... (0.00)
Posted by PeterI on 2012-06-28, 17:08:48 (174.51.102.111)
...tubes for the 12AU7 positions. I'd love to try E80CCs, but they're not cheap. I might have to cough up real money (gasp!). Meanwhile, I find 6CG7s down in my sofa cushions. I was referring to (sold .......
435: Tubes Asylum, Thanks for suggestions ... (0.00)
Posted by PeterI on 2012-06-28, 06:39:09 (174.51.102.111)
I'm not sure what i would use for an active pre. Non-tube would be out of the question, I think. Maybe I shoulda kept my last Eico HF85. I would rather keep from putting new, extra stuff in the signal .......
436: Tubes Asylum, Chassis pic (0.00)
Posted by PeterI on 2012-06-27, 16:43:42 (174.51.102.111)
Underneath. Circuit unaltered, just a lotta new parts. I think the CL-190 'inrush limiter' is worthless. Not sure it does its job. .......
437: Tubes Asylum, Heath monoblocks complete, sounding very good (picture) (0.00)
Posted by PeterI on 2012-06-27, 13:02:22 (174.51.102.111)
My Hk W-5M amp restoration has paid off. I'm hearing very good things. I haven't done a head-to-head comparison yet with my (on the shelf) Eico HF81. Maybe apples n oranges. The new SDS board power .......
438: Tubes Asylum, more on Hk W-5m restoration, passive preamp? (0.00)
Posted by PeterI on 2012-06-19, 13:41:25 (174.51.102.111)
The work is progressing. But I am finding lower volume - I think I should leave out one of the 15kohm resistor on the input. Max volume is just ok, would like to raise it. Man, these voltages are .......
439: Tubes Asylum, RE: Heathkit W-5M. a couple questions - thanks... (0.00)
Posted by PeterI on 2012-06-12, 04:42:04 (174.51.102.111)
Thank you for your helpful advice. While I've restored a number of amps , these are a different sort of beast. Pete .......
440: Tubes Asylum, Heathkit W-5M. a couple questions (0.00)
Posted by PeterI on 2012-06-11, 18:46:14 (174.51.102.111)
Now that I have the HK W-5m amplifiers to work on, I'm finding the transformers are OK (16458 OPTs). In other words, the problems aren't there. I'm getting undistorted music but keeping supply at 1 .......
441: Tubes Asylum, RE: DCResistance Transformer checks on W5, Thanks (0.00)
Posted by PeterI on 2012-06-01, 13:33:57 (174.51.100.69)
Thanks for the detailed info. Will be turning these over on the bench soon. Peter .......
442: Tubes Asylum, Heathkit W-5m Transformer checks (picture) (0.00)
Posted by PeterI on 2012-05-31, 18:34:40 (174.51.100.69)
A couple of weeks go I asked some questions about 6L6G amplifiers and got some helpful responses, mainly that most 6L6-type amps make such high plate voltages that these old 6L6Gs I have won't hold .......
443: Vintage Asylum, I had Russian K40s in... (0.00)
Posted by PeterI on 2012-05-16, 10:48:50 (174.51.100.69)
.33uf, IIRC. Had very good tubes, but would've liked to experiment more w/ them. I'm loving EL84 amplifiers, after so many experiments with various amps.. You wouldn't believe the gear that has gon .......
444: Vintage Asylum, RE: The original was warmer and richer, ... (0.00)
Posted by PeterI on 2012-05-14, 14:15:48 (174.51.100.69)
I had the VTA ST-70 ( the version with 12AT7) and to me it sounded like a transistor amplifier. Sold it. Some wouldn't mind that, but then why have a vintage tube amp? Maybe the 12AU7 version would've .......
445: Tubes Asylum, RE: 6L6 amplifiers. which one? - affordable. (0.00)
Posted by PeterI on 2012-05-13, 13:59:33 (174.51.100.69)
Thanks Mike. I don't doubt a pair of restored W5s are great. I just found a wacky old Hickok 532 tube tester (1950?). Seems to actually work! Peter .......
446: Tubes Asylum, RE: 6L6 amplifiers. which one? - affordable. (0.00)
Posted by PeterI on 2012-05-12, 16:38:18 (174.51.100.69)
Thanks for input. That NS is tempting. After years with very good 7591 amps (Fisher, Scott) I went thru a lifestyle change that meant smaller gear and lower volumes. I have been loving vintage EL84 am .......
447: Tubes Asylum, 6L6 amplifiers. which one? - affordable. (0.00)
Posted by PeterI on 2012-05-12, 12:28:36 (174.51.100.69)
I have more 6L6G and 6L6GA's than i can shake a stick at. I'll keep 4 and sell the others to buy an audio amplifier. I tested a pair of Heathkit W5-somethings once but they were overly complicated to .......
448: Tubes Asylum, RE: First post in the Tube Asylum - speakers? (0.00)
Posted by PeterI on 2012-05-09, 13:25:08 (174.51.100.69)
That's great. Tell us your speakers and your music source as well, I'd like to know. cheers Pete (I agree on the Steely Dan song also) .......
449: Vintage Asylum, Thanks for input. nt (0.00)
Posted by PeterI on 2012-04-06, 08:41:16 (174.51.100.69)
nt .......
450: Vintage Asylum, What would make a SS amp go blazing hot on... (0.00)
Posted by PeterI on 2012-04-05, 14:49:09 (174.51.100.69)
one side only, so hot you can't touch the heat sinks? Bad power transistors dumping juice to ground? It finally blew a fuse on the board + input. (it only took 15 seconds for it to happen.). It's a .......
451: Tube DIY Asylum, RE: The most recent picture you posted..... (0.00)
Posted by PeterI on 2012-04-03, 08:38:40 (174.51.100.69)
That's very helpful. I should have mentioned it is certainly bipolar with + and - 60V. I don't mind rebuilding these boards, but hi-quality parts were used: Sprague, Dale, GE, etc. 90% of the work .......
452: Tube DIY Asylum, that's a good idea... (0.00)
Posted by PeterI on 2012-04-02, 14:39:36 (174.51.100.69)
hopefully it won't become "lots of unsoldering". :) The traces are thick brass/copper. cheers .......
453: Tube DIY Asylum, Thanks, i will have to determine ... (0.00)
Posted by PeterI on 2012-04-02, 14:35:25 (174.29.4.101)
type. I could try those transistors but naturally don't want to do harm. I thought maybe I could determine whether PNP or NPN while in circuit but likely not. I'll carefully desolder. However I think .......
454: Tube DIY Asylum, Thanks for input, i think this may help... (pic) (0.00)
Posted by PeterI on 2012-04-02, 09:22:03 (174.51.100.69)
Thanks Tim and Ray. The transistors have 60+ VDC on them but i can't determine if they are PNP or NPN. Due to the one-off nature of this amp, there's no schematic. I could desolder them if that hel .......
455: Tube DIY Asylum, Transistor question - picture (0.00)
Posted by PeterI on 2012-04-01, 07:53:25 (174.51.100.69)
I'm wondering if some expert here can help me. I am repairing a homebrew SS amplifier i picked up recently and trying to save it. It appears to need 2 driver board transistors, as I measure shorts .......
456: Vintage Asylum, RE: Fantastic DIY Amplifier I got at the Vintage Voltage Expo (picture) (0.00)
Posted by PeterI on 2012-03-30, 18:07:51 (174.51.100.69)
It appears to need 2 driver board transistors. These are labelled w/ Motorola logo and "4-395". I can't find any cross-reference. They have TO39 configuration. Pete .......
457: Vintage Asylum, Fantastic DIY Amplifier I got at the Vintage Voltage Expo (picture) (0.00)
Posted by PeterI on 2012-03-25, 15:17:12 (174.51.100.69)
I got this apparently home-made SS power amplifier at the Denver show. It sounds great! Rated over 200 w/ch. I can't believe the driver boards are DIY, acid etched. May be they were from a kit. It .......
458: Vintage Asylum, RE: Which amplifier to have restored? (0.00)
Posted by PeterI on 2011-10-20, 17:00:40 (174.51.100.69)
"as long as you check for grid to ground resistance limit violations. JJ's Octal production has been inconsistent (at best) and should be passed up. " you made my point with the above quote, Eli. Sylv .......
459: Vintage Asylum, RE: Which amplifier to have restored? (0.00)
Posted by PeterI on 2011-10-20, 09:57:09 (174.51.100.69)
I've had 3 of those, the Scotts and the Fisher 500b. If you can go low power with your speakers the 299a is going to sound great. But it's more 'primitive' than the others. The Scott 299D needs good .......
460: Vintage Asylum, The restored tonearm on TT (or, the "Better than Nothing" Dept) pic (0.00)
Posted by PeterI on 2011-10-18, 14:45:13 (174.51.100.69)
The cleaned up arm with the non-matching headshell. (actually doesn't have 2 draw pins but diameter of mount is different than 'standard'.) Sounds fantastic. Pete .......
461: Vintage Asylum, yes, true... (0.00)
Posted by PeterI on 2011-10-08, 11:48:47 (174.51.100.69)
and you helped me in my original query regarding Empire tonearms a few weeks ago. Now that the 98 tonearm is in my sweaty hands, I find the depth of the insertion is different and the 4 pins don't lin .......
462: Vintage Asylum, RE: Empire headshell - anyone have one ? Thx (0.00)
Posted by PeterI on 2011-10-07, 17:38:12 (174.51.100.69)
thanks for the tip. why didn't i find that tonearm on an ebay search? because the guy spelled 'tonearm' wrong. lol Pete (bingo, won the parts tonearm, btw.) .......
463: Vintage Asylum, Empire headshell - anyone have one ? pic (0.00)
Posted by PeterI on 2011-10-06, 14:01:32 (174.51.100.69)
I am looking for a headshell for the old Empire tonearm shown here. A helpful asylum member identified the tonearm as Empire 98 (980). Standard headshells don't fit right because this headshell nee .......
464: Vintage Asylum, RE: Thx, i could also change tonearm. G301 (0.00)
Posted by PeterI on 2011-09-21, 11:28:47 (174.51.100.69)
I'd get another vintage style tonearm, put it on a new exotic wood sideboard. I'm beginning to picture a nice low heavy plinth like this one i built in 2007. Pete .......
465: Vintage Asylum, RE: thanks to responders (another pic) (0.00)
Posted by PeterI on 2011-09-21, 08:41:00 (174.16.103.178)
Thank you for advice. I have had sooo many TTs but never an Empire. The connection certainly looks like a normal headshell would fit. This should be a fun project. Pete .......
466: Vintage Asylum, Lucky me. My brother is sending me a Thorens 124, but...(pic) (0.00)
Posted by PeterI on 2011-09-20, 21:04:34 (174.51.100.69)
I'm getting a Thorens TD124 but I don't recognize the tonearm. I think it's Thorens OEM (?). The headshell is missing. Wondering if the original type can be found, or whether an aftermarket SMC-sty .......
467: Vintage Asylum, RE: Any good Magnavox Tube Stereo Consoles? yes (0.00)
Posted by PeterI on 2011-08-18, 10:55:08 (174.51.100.69)
But i've pulled amplifiers from cabinets. Here's two of my Maggie projects. they need modifying because they were tuned to the attached speakers. Pete .......
468: Vintage Asylum, NOS 5751WAs will get big money... (0.00)
Posted by PeterI on 2011-07-09, 07:13:28 (174.51.100.69)
if you decide to sell them, and can verify them w/ testing. Pete .......
469: Tubes Asylum, thanks for all input. (0.00)
Posted by PeterI on 2011-06-29, 12:56:21 (174.51.100.69)
after testing it was looking like that was it, but wasn't sure about CT ground. thx Pete .......
470: Tubes Asylum, Filament transformers for 6 and 12V tubes? (0.00)
Posted by PeterI on 2011-06-28, 13:32:34 (174.51.100.69)
I have a couple older, good quality filament transformers I want to use for a project. Rated at 12.6VAC output, 3A. How do you wire to supply 6.3V filament tubes? Each leg (green) to center tap? How .......
471: Vintage Asylum, RE: Lite resto of Pilot 602 SA tube receiver -Thanks (0.00)
Posted by PeterI on 2011-06-23, 19:34:38 (174.51.100.69)
Thanks for the background info. Yes, the AM/FM design really dates this, as does the overall look. Not as tied to the decade as a VOM or Heathkit amplifier but very much 'of the period'. now to get th .......
472: Vintage Asylum, Lite resto of Pilot 602 SA tube receiver - pictures (0.00)
Posted by PeterI on 2011-06-23, 10:13:42 (174.51.100.69)
This newly upgraded Pilot tube 602SA receiver (1963) is sounding very good. Some new tubes, coupling caps (old originals read many volts at output), and some better power supply parts. Sounds as .......
473: Vintage Asylum, Yes, most are, but... (0.00)
Posted by PeterI on 2011-06-18, 11:24:14 (174.51.100.69)
I had older S-60s (or were they S-65s?). Four excellent Danish drivers each, handsome as hell with the rosewood and metal trim. But why didnt they sound better? I think an overly-complicated crossover .......
474: Vintage Asylum, yes, agreed Mike. remember the Beogram 8000 i posted? (0.00)
Posted by PeterI on 2011-06-17, 20:36:33 (174.51.100.69)
i sold it cheap, minor issues, even after many hours of work, resoldering the boards. Damn, it sounded good, and looked super-hip. Peter .......
475: Vintage Asylum, the other sacred oath is no more B&O... (0.00)
Posted by PeterI on 2011-06-17, 17:16:21 (174.51.100.69)
since Bang & Olufsen is Danish for "trouble". (but after MANY units, mostly TTs, I understand the attraction). Peter .......
476: Vintage Asylum, went to an estate sale today with about 20+ RTRs... (0.00)
Posted by PeterI on 2011-06-17, 15:38:50 (174.51.100.69)
it was crazy, like someone had an obsession for years. Akai, Teac, Sony, a few others. Better quality, but not TOTL. And this was after several had sold, I am sure. Asking 40 bucks apiece but i swore .......
477: Tubes Asylum, RE: Amperex 12AX7 orange globe: British -picture (0.00)
Posted by PeterI on 2011-06-17, 06:04:45 (174.51.100.69)
Here's an Amperex 12AX7 made in Britain w/ the orange globe. Codes seem to indicate '70s manufacture and Blackburn factory. I have another w/ orange printing but no globe. Pete .......
478: Vintage Asylum, thanks for the explanation. (0.00)
Posted by PeterI on 2011-05-31, 15:43:37 (174.51.100.69)
I was seeing the 'trend' in various sources, but wasn't sure exactly why. maybe just stay w/ stock values. Pete .......
479: Vintage Asylum, cheers... (0.00)
Posted by PeterI on 2011-05-31, 10:41:42 (216.160.139.71)
David, glad to hear from you. I like those old VOMs. Pete .......
480: Vintage Asylum, Is it standard practice to increase value of coupling caps? (0.00)
Posted by PeterI on 2011-05-30, 12:39:22 (107.2.185.22)
It seems in the 5 years i've been restoring old tube amps, the general consensus on this board appears to be to increase the value of the coupling capacitors to power tubes. This is standard with Dyna .......
481: Vintage Asylum, RE: fisher 680a (picture) (0.00)
Posted by PeterI on 2011-05-25, 18:42:19 (174.51.100.69)
Here's what mine looked like after i fixed it up. It was a great amp, but needed a couple minor mods to make it work without its preamp (elsewhere in the console). I don't remember much about that, .......
482: Vintage Asylum, RE: I want to rebuild a Scott 299D (0.00)
Posted by PeterI on 2011-05-09, 13:45:20 (174.51.100.69)
Yeah, you definitely wouldn't want this to be your first one. Complicated. I started working on tube amps in 2006, taught myself, and now I've done about 25+ vintage amps/preamps since. It depends on .......
483: Vintage Asylum, RE: I want to rebuild a Scott 299D (0.00)
Posted by PeterI on 2011-05-09, 12:51:06 (174.51.100.69)
Great amplifer. Lots of info on the web. Picture is mine underneath, before I traded/sold it to a friend. There's a long AudioKarma discussion you can find easily. The link below is to a page by t .......
484: Tubes Asylum, Thanks to respondents, Jim and Tre. I switched tubes... (0.00)
Posted by PeterI on 2011-05-04, 07:53:10 (174.51.100.69)
and the problem disappeared. I had changed out all 6 of the power tube sockets and rectifier sockets, but i had triple-checked my work, so i knew it wasn't that. Had older russian 6pi14pi tubes in for .......
485: Tubes Asylum, Minor tech question - measured 1.5V at ... (Eico HF81) (0.00)
Posted by PeterI on 2011-05-03, 17:42:38 (174.51.100.69)
1.5V DC at pin 2 on one of the EL84s in my Eico HF81. The coupling caps are brand-new russian PIO .033uf. Does this mean one or more are leaking? I should have Zero volts there. Minor voltage (.3V) .......
486: Vintage Asylum, What I did was... (0.00)
Posted by PeterI on 2011-04-28, 07:33:15 (174.51.100.69)
...keep the thick front and back panels. That way they retained their stock speaker openings. I knocked the old beat-up boxes apart with a few taps of a hammer. Joints not strong. I recut the front .......
487: Tubes Asylum, Thanks very much. NT (0.00)
Posted by PeterI on 2011-04-23, 07:37:27 (174.51.100.69)
nt .......
488: Tubes Asylum, Is this a Mic preamp? Langevin (picture) (0.00)
Posted by PeterI on 2011-04-22, 08:20:26 (174.51.100.69)
I'm sure someone here knows something about this little tube component, 5116 amp. It has 2-5879 tubes. I think it came out of a recording studio. I have another that has Universal Audio 1016 xforme .......
489: Vintage Asylum, Nice picture. (0.00)
Posted by PeterI on 2011-04-09, 18:27:00 (174.51.100.69)
I had one as well. Startlingly good, and adequate power. I also love to combine the very old tech with new. Peter .......
490: Tubes Asylum, thanks for info. NT (0.00)
Posted by PeterI on 2011-03-29, 06:03:50 (174.51.100.69)
nt .......
491: Vintage Asylum, RE: Vintage Voltage Expo Colorado - Slide Show (0.00)
Posted by PeterI on 2011-03-28, 12:27:19 (174.51.100.69)
Ha, good point. Yes, mostly an over 50 crowd, especially in the Colorado Radio Club - they always put up a great display. But lots of wives/SOs in tow, and many 20-somethings looking for turntables an .......
492: Vintage Asylum, Thanks for posting. it was a good show. (0.00)
Posted by PeterI on 2011-03-28, 12:23:26 (174.51.100.69)
I see some of my friends in those pics, and the gal that runs it. I bought some speakers, tubes, and misc stuff. Some prices high, but lots to look at nonetheless. thanks for posting, Pete ::: TOPIC:: .......
493: Tubes Asylum, ECC83 tubes with big holes in plates - ID (pictures) (0.00)
Posted by PeterI on 2011-03-27, 13:54:10 (174.51.100.69)
I got these 2 matching 12AX7-ECC83 tubes in an old industrial component. They read "RCA Gt Britain", but i know from experience that does not mean they were actually made in Britain. Are they E .......
494: Vintage Asylum, RE: anyone have a knob like this? (0.00)
Posted by PeterI on 2011-03-11, 09:23:07 (174.51.100.69)
post deleted .......
495: Vintage Asylum, funny! nt (0.00)
Posted by PeterI on 2011-03-11, 03:51:21 (174.51.100.69)
nt .......
496: Vintage Asylum, RE: anyone have a knob like this? (0.00)
Posted by PeterI on 2011-03-10, 10:52:38 (174.51.100.69)
thanks for input. i use AES a lot, will look at their site. i could use those knobs 'at gunpoint'. Pete .......
497: Vintage Asylum, anyone have a knob like this? (pic) (0.00)
Posted by PeterI on 2011-03-10, 07:00:49 (174.51.100.69)
post deleted .......
498: Vintage Asylum, Mike, PM'd you about C20 knob - nt (0.00)
Posted by PeterI on 2011-03-07, 18:59:37 (174.51.100.69)
nt .......
499: Vintage Asylum, the 'stoned' part is how unbelievably bad the writing is.. . (0.00)
Posted by PeterI on 2011-03-06, 18:28:34 (174.51.100.27)
but it happens i have a line on one of these C20s locally. Saw value closer to 1300 w/ wood case. and only one picture in the ad? well, they ARE 15 cents for extras (sarcasm). Are the upper knobs avai .......
500: Vintage Asylum, RE: Vintage Blues (0.00)
Posted by PeterI on 2011-03-03, 14:39:28 (174.51.100.69)
I have offered full refunds to any buyer who bought a vintage component from me. But i remind them, with complete honesty, that if they sell it back, i will sell it to someone else, and they will neve .......
Found total of 500 records, Query: , Author: PeterI in All Forums, Time: 1 sec.