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1: Hi-Rez Highway, Qobuz App (0.00)
Posted by deafbykhorns on 2024-02-08, 18:38:25 (73.192.33.52)
I repeat, do not update the Qobuz application for Iphone or Ipad, update has bricked the application. Qobuz is impossible to contact Time to try Tidal .......
2: Amp/Preamp Asylum, RE: Nuance Audio gm70 mono amps (0.00)
Posted by deafbykhorns on 2023-11-08, 10:06:52 (96.94.54.195)
I spent $5000 in parts just to build mine. I suspect the savings are in the transformers and power supply. Mine also drives the tube into A2 which also costs more to implement. This will give you pow .......
3: Amp/Preamp Asylum, RE: 300b driver for Cary CAD-805 AE/211 output (0.00)
Posted by deafbykhorns on 2023-11-08, 10:02:55 (96.94.54.195)
Have you tried a JJ300B? I use this to drive a GM70 and it works well. I have tried EML and it ended up arcing. .......
4: Tube DIY Asylum, RE: Help!! Hum on restored vintage tube amp (0.00)
Posted by deafbykhorns on 2023-09-13, 18:29:03 (73.192.33.52)
It's a ground loop .......
5: Tube DIY Asylum, RE: Resistor used for measuring bias keeps failing -- what can I do? (0.00)
Posted by deafbykhorns on 2023-09-01, 11:44:51 (96.94.54.195)
^^^ What Paul said makes more sense. .......
6: Tube DIY Asylum, RE: Resistor used for measuring bias keeps failing -- what can I do? (0.00)
Posted by deafbykhorns on 2023-08-28, 12:14:49 (96.94.54.195)
The resistor will also act as a fuse and save a OPT transformer. Bias must be drifting, i would guess no more than a 1/2 watt. .......
7: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-12, 18:39:02 (71.203.171.238)
Just got a plot sent to me from Bert. They look pretty darn good on paper, i'll join the forum. I really don't want to go down another rabbit hole without hearing them. Lol, I don't see much of those .......
8: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-12, 12:23:02 (96.94.54.195)
I live in Jacksonville near the Mayo Clinic. Boat is in the back yard on a lift, ready to go at any time. We have snapper opening up this weekend. Right now, Cobia are on the wrecks and big shark. We .......
9: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-12, 11:34:06 (96.94.54.195)
I have family in Buffalo but that's another 14 hrs to Minn. but I could always catch a puddle jumper. We get those tarpon up here in late spring and fall, fun to catch. But catching a Cobia on a knuck .......
10: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-12, 04:42:07 (71.203.171.238)
Just got a plot sent to me from Bert. They look pretty darn good on paper, i'll join the forum. I really don't want to go down another rabbit hole without hearing them. Lol, I don't see much of those .......
11: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-11, 16:13:56 (71.203.171.238)
I'd love to hear those horns but judging by your fish signature you are far north of me. I have owned my khorns since 1985, paid $1600 new back then. Purchased upgrades from Alk in 2005 including the .......
12: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-10, 18:01:33 (71.203.171.238)
Not aware of a Oris with compression drivers, just the 150 which i wouldnt be interested .......
13: Tube DIY Asylum, RE: More elegant alternative? (0.00)
Posted by deafbykhorns on 2023-07-10, 11:16:54 (96.94.54.195)
They must be a specialty company... I'm in the electrical industry and fuses are quicker than breakers and also have higher fault current ratings. .......
14: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-10, 11:08:21 (96.94.54.195)
No, none of the horns would be time aligned with the bass cabinet including the original horn Paul Klipsch designed. I think its a little more complicated than that (getting a time aligned horn and id .......
15: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-10, 06:28:18 (96.94.54.195)
My Khorns currently have Volti's wood horns with the BMS 4592mid 16ohm drivers, tweeter is a JBL 2404. Previously, i had the Martinelli Horns using the original drivers. I had Alks extreme slope cross .......
16: High Efficiency Speaker Asylum, RE: Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-07-04, 18:48:30 (96.94.54.195)
edit truncated my entire reply... .......
17: High Efficiency Speaker Asylum, Klipsch Jubilee (0.00)
Posted by deafbykhorns on 2023-06-15, 12:42:17 (96.94.54.195)
Has anyone auditioned or purchased these? They are much larger than the underground Jubs so the WAF is low. I currently have modified Khorns with 2" format wood horns and BMS drivers. .......
18: SET Asylum, RE: My Decware Zen clone (0.00)
Posted by deafbykhorns on 2023-04-08, 18:47:18 (71.203.171.238)
I've always liked your builds. I'm sure the wiring underneath looks like the outside! .......
19: SET Asylum, RE: a GM70 (0.00)
Posted by deafbykhorns on 2023-03-30, 07:44:37 (96.94.54.195)
Its an excellent tube and easy to drive. .......
20: Tube DIY Asylum, RE: New tax laws are NOT helping tube sales... (0.00)
Posted by deafbykhorns on 2023-02-16, 05:51:05 (96.94.54.195)
Facebook marketplace is becoming more popular now for sales... No IRS reporting as of yet. .......
21: Tube DIY Asylum, RE: Mastersound update (0.00)
Posted by deafbykhorns on 2023-01-23, 18:16:55 (71.203.171.238)
Power supply .......
22: Tube DIY Asylum, Mastersound update (0.00)
Posted by deafbykhorns on 2023-01-23, 18:14:34 (71.203.171.238)
Got schematics but trying to figure out power supply voltages. Most of it I can figure out except for bias, cathode resistors are 310 ohms and bias at the top of cathode resistor should be 18-20v. I m .......
23: SET Asylum, RE: Just one question, (0.00)
Posted by deafbykhorns on 2022-11-11, 05:37:31 (96.94.54.195)
OPT's are fine. All the fuses installed per spec so no telling what caused the problem. I'm guessing heat killed it from all the drippings. .......
24: SET Asylum, RE: Mastersound 300B (Vaic) (0.00)
Posted by deafbykhorns on 2022-11-10, 10:51:54 (96.94.54.195)
That article states cathode bias but I'm pretty sure its fixed bias. .......
25: SET Asylum, Mastersound 300B (Vaic) (0.00)
Posted by deafbykhorns on 2022-11-09, 10:24:12 (96.94.54.195)
I have an original Mastersound (Vaic) 300 B amplifier with a blown transformer. Looking for a schematic or someone that can measure the AC output so I can find something to fit the xfrmr case. The US .......
26: Tube DIY Asylum, RE: Citation V Progress (0.00)
Posted by deafbykhorns on 2022-08-25, 07:06:43 (96.94.54.195)
Very nice Are you using the original turret boards? Nice addition with the grounding wire, that's exactly how I do my grounding as well. .......
27: Tube DIY Asylum, RE: Best Cable Tie Holders? (0.00)
Posted by deafbykhorns on 2022-06-03, 11:10:37 (96.94.54.195)
I have used both 3m 5200 and a product from Ace Hardware called E6000. So far, both have stood the test of time over a 5yr period. I have used 5200 in marine environments and it works well in the offs .......
28: Tube DIY Asylum, RE: Best Cable Tie Holders? (0.00)
Posted by deafbykhorns on 2022-06-03, 09:44:25 (96.94.54.195)
I never purchased the epoxy version but removed the double sided tape and glued. With the heat in a chassis, they come loose quicker than you would think. .......
29: Tube DIY Asylum, RE: Can a Voltage Doubler Work Right Off Of Line Voltage? (0.00)
Posted by deafbykhorns on 2022-02-18, 05:10:00 (96.94.54.195)
Dangerous but the chinese do it all the time with current limiters. I see it in the lighting world on drivers. .......
30: Tube DIY Asylum, RE: Hammond Interstage Transformers (0.00)
Posted by deafbykhorns on 2022-02-14, 08:18:02 (96.94.54.195)
I used one to drive the grid of a GM70 with a bit of A2. It worked pretty darn good but in the end it wasnt enough ma for the driver tube so I had one custom made. .......
31: Tube DIY Asylum, RE: "more presentable" (0.00)
Posted by deafbykhorns on 2022-01-13, 17:06:07 (76.122.44.79)
I believe you might of motivated me to try those LV supplies. They work well but wasnt sure about long term reliability since the parts are low end. I believe they ran about 50-60khz .......
32: Tube DIY Asylum, RE: 211 SET Progress (0.00)
Posted by deafbykhorns on 2022-01-12, 16:53:12 (76.122.44.79)
I did the same thing on my GM70, definitely need a slow start circuit. I got some criticism with the extra capacitance but studied some other amps like the Cary 805 that go well into A2. So I took a .......
33: Tube DIY Asylum, RE: Yay! Signal Has Them! (0.00)
Posted by deafbykhorns on 2022-01-03, 05:20:43 (96.94.54.195)
I take the same approach with our business. I refuse to purchase Chinese LED lighting even if I'm bidding against contractors that use it all the time. I would rather lose a job than use that garbage. .......
34: Tube DIY Asylum, RE: Edcor (0.00)
Posted by deafbykhorns on 2021-12-31, 16:22:57 (76.122.44.79)
wound some decent transformers. Not the best paint job but performed well. Monolith magnetics is another source and good folks. Expensive but nice transformers .......
35: Tube DIY Asylum, RE: McIntosh 240 (0.00)
Posted by deafbykhorns on 2021-12-28, 11:31:14 (96.94.54.195)
I sold my entire McIntosh collection after building DIY amps. The McIntosh look great on paper for a tube amp and drive some speakers well but there's better sounding amps out there. Reminds me of Aud .......
36: Tube DIY Asylum, RE: 300B IT 1:1 845, A2 possible? (0.00)
Posted by deafbykhorns on 2021-12-28, 11:29:01 (96.94.54.195)
I'll have to dig out some old posts but I looked at the 805c circuit which is nothing more than a IT coupled driven by a 300b. I'm doing something similar with a GM70 and easily getting A2 out of it a .......
37: SET Asylum, RE: A watt is a watt! (0.00)
Posted by deafbykhorns on 2021-12-23, 10:45:09 (96.94.54.195)
Maybe its a watt at 20hz??? A watt at 1Khz most likely won't produce a watt at 20hz on a tube amp. .......
38: Tube DIY Asylum, RE: 5a4rgz34 rectifier tube replacement (0.00)
Posted by deafbykhorns on 2021-12-18, 17:06:34 (76.122.44.79)
Yep .......
39: Tube DIY Asylum, RE: Wow, I might stick with the trophy shop laser (0.00)
Posted by deafbykhorns on 2021-11-23, 10:24:49 (96.94.54.195)
engraving. That sound like a lot of work. .......
40: Tube DIY Asylum, RE: man, that's a handful for sure (0.00)
Posted by deafbykhorns on 2021-11-22, 17:00:56 (76.122.44.79)
The cadd work can be time consuming unless you do it every day. I'm much better at cadd than I am at design so it was a piece of cake for me. That pre planning and level of machine work really makes y .......
41: Tube DIY Asylum, RE: Where is IMD? (0.00)
Posted by deafbykhorns on 2021-11-21, 18:00:47 (76.122.44.79)
You're right about one thing, many of us enjoy doing the work as much or more than the actual music itself. Might be our aging ears or our tinnitus doesn't make it as enjoyable. .......
42: Tube DIY Asylum, RE: Recent Project Completed (0.00)
Posted by deafbykhorns on 2021-11-21, 17:49:57 (76.122.44.79)
Very nice work as usual. How do you do your lettering? .......
43: Tube DIY Asylum, G5K Aa tube socket (0.00)
Posted by deafbykhorns on 2021-11-18, 17:48:02 (76.122.44.79)
Anyone know where to find these tube sockets? .......
44: Tube DIY Asylum, RE: 394a tube and Hickok 539 tester (0.00)
Posted by deafbykhorns on 2021-11-17, 17:53:26 (76.122.44.79)
Without the 1k resistor, does it conduct? .......
45: Tube DIY Asylum, RE: 394a tube and Hickok 539 tester (0.00)
Posted by deafbykhorns on 2021-11-14, 18:51:22 (76.122.44.79)
I might try them on my 01a preamp first If i use them on my 300b then i need to use the top cap. Do you take a 1k to the grid? .......
46: Tube DIY Asylum, RE: 394a tube and Hickok 539 tester (0.00)
Posted by deafbykhorns on 2021-11-11, 11:59:39 (76.122.44.79)
Rectifier I figured out the heater settings but can't find the grid and anode settings. Edit Found a post from Pete Millett Its basically the same as a TV7 test HR4000 Shunt is more like 90 on my 539 .......
47: Tube DIY Asylum, 394a tube and Hickok 539 tester (0.00)
Posted by deafbykhorns on 2021-11-10, 15:52:54 (76.122.44.79)
Anyone know the settings to test this tube? Fits a standard 8 pin socket 2 and 7 are filament, 4 grid, top cap anode .......
48: Tube DIY Asylum, RE: Widows and tube stashes (0.00)
Posted by deafbykhorns on 2021-11-08, 16:13:30 (76.122.44.79)
I have a similar stash, almost looks just like yours...- Except for a handful of the exotic tubes .......
49: Tube DIY Asylum, RE: Photo (0.00)
Posted by deafbykhorns on 2021-10-08, 17:29:07 (76.122.44.79)
The Citation V are difficult to find anymore and getting top dollar. Might be a good time to sell it if your other amps are better. I'm dumping most my commercial equipment myself after finding i can .......
50: Tube DIY Asylum, RE: Photo (0.00)
Posted by deafbykhorns on 2021-10-08, 10:08:57 (96.94.54.195)
How does it compare to the Citation? .......
51: Tube DIY Asylum, RE: I laser etch all my stuff (0.00)
Posted by deafbykhorns on 2021-10-07, 16:53:53 (76.122.44.79)
My local trophy shop charge $85 for engraving 4 plates. Yes, its black with raw aluminum .......
52: Tube DIY Asylum, RE: I laser etch all my stuff (0.00)
Posted by deafbykhorns on 2021-10-07, 12:48:03 (96.94.54.195)
You can get various depths, it depends on the machine they are using. I have seen engraving done with color fill but don't recall where. Oddly, bare anodized aluminum turns out black and looks good as .......
53: Tube DIY Asylum, RE: I laser etch all my stuff (0.00)
Posted by deafbykhorns on 2021-10-07, 09:53:37 (96.94.54.195)
Black anodized chassis from Landfall Systems. I did all the machining layout in Cadd, Landfall did the CNC work. Used cadd again and did an overlay of text/artwork and gave the trophy shop a file, i b .......
54: Tube DIY Asylum, RE: I laser etch all my stuff (0.00)
Posted by deafbykhorns on 2021-10-07, 06:49:58 (96.94.54.195)
Laser etching works great, see attached picture of my recent build. This was done at a trophy shop, I just gave them a file with my artwork. .......
55: Tube DIY Asylum, RE: How does it sound/perform? (0.00)
Posted by deafbykhorns on 2021-08-12, 10:30:50 (96.94.54.195)
Sounds like a fair assessment. I have 104db speakers on some JJ2A3's and really like the sound at lower levels. When it comes to concert levels, i bust out the GM70amps. .......
56: SET Asylum, RE: Mastersound Reference 845 SET Amp (0.00)
Posted by deafbykhorns on 2021-08-11, 17:45:01 (76.122.44.79)
I believe you might have more inrush current with that tube. Don't remember the cap size but it should be under 4 or 5uf with that tube. If so, go for it, I use that tube on my 2A3 amp .......
57: Tube DIY Asylum, RE: How does it sound/perform? (0.00)
Posted by deafbykhorns on 2021-08-11, 17:38:20 (76.122.44.79)
. .......
58: Tube DIY Asylum, RE: Grid Choke (0.00)
Posted by deafbykhorns on 2021-07-25, 18:47:15 (174.211.228.85)
I'd expect no less from the midlife crisis guy! Impressive! I don't know what it is about that 01A tube but it makes any of my amps come to life, even the solid-state amps I have laying around H .......
59: Tube DIY Asylum, RE: Grid Choke (0.00)
Posted by deafbykhorns on 2021-07-25, 18:11:51 (76.122.44.79)
Wow, never thought about reducing volume that way in my 01A. It drives an AVC also but led biased with a gyrator. Using one of Dave Slagles AVC with excellent results .......
60: Tube DIY Asylum, RE: Grid Choke (0.00)
Posted by deafbykhorns on 2021-07-25, 16:44:03 (76.122.44.79)
I used a gyrator on my 01A preamp coupled to an AVC with good results. Why a step up on your 01A? .......
61: Tube DIY Asylum, RE: Fixed Cathode Bias (0.00)
Posted by deafbykhorns on 2021-07-20, 16:55:56 (76.122.44.79)
You had to pull out the pic again. .......
62: Tube DIY Asylum, RE: Fixed Cathode Bias (0.00)
Posted by deafbykhorns on 2021-07-20, 16:03:44 (76.122.44.79)
That schematic haunts me.... I'd love to build something like that one day. I have a stash of large triodes .......
63: Tube DIY Asylum, RE: Designed obsolescence (0.00)
Posted by deafbykhorns on 2021-07-18, 05:12:48 (76.122.44.79)
The higher pressures with the new freon didn't help matters which is why they eventually leak quicker than R22. My outdoor unit leaked after 5yrs, it was the equivalent Trane unit which lasted 23yrs(c .......
64: SET Asylum, RE: I built nothing but DHT SET until I got hooked on Mahler (0.00)
Posted by deafbykhorns on 2021-06-14, 09:30:18 (96.94.54.195)
I went back and read some of the threads in DIY. Are you BillEpstein or tubemack (Florida)? I'm in Florida but get up to the smokeys to mountain bike a couple times a year. Hammond has some respectabl .......
65: SET Asylum, RE: I built nothing but DHT SET until I got hooked on Mahler (0.00)
Posted by deafbykhorns on 2021-06-14, 04:23:35 (96.94.54.195)
Nice looking amps I have 65W SET amps at about $90 a watt and that was using monolith magnetics iron. I think the amps quality is mostly in the OPT. Looks like you may have some magnequest OPT's? ::: .......
66: SET Asylum, RE: Something New Under the Sun? (0.00)
Posted by deafbykhorns on 2021-06-13, 08:30:26 (76.122.44.79)
Did you see the price of the 97A monoblocks? $1562 per watt isnt too bad for a 5watt amp but 80watts @ ouch! .......
67: Tube DIY Asylum, RE: ARC Classic 150 Problem (0.00)
Posted by deafbykhorns on 2021-05-30, 18:54:17 (76.122.44.79)
Those amps are not easy to work on, you better get some help with that one. It could be amp section is not operating or just the protective circuit .......
68: SET Asylum, RE: Here we go..... (0.00)
Posted by deafbykhorns on 2021-05-10, 13:00:53 (96.94.54.195)
Those old sand resistors were 25w each, parallel, unmounted. The replacements are 1-50watt, unmounted. Look at the circuit and the original thread. Bias is typically set at 15v across those resisto .......
69: Tube DIY Asylum, RE: Power supply (0.00)
Posted by deafbykhorns on 2021-05-10, 04:48:26 (96.94.54.195)
You need to build a good power supply to make that tube work correctly. Once you get it right, the 01A will be your last preamp. My 01A preamp will make a good SS amp sound better. I use it in front o .......
70: Tube DIY Asylum, RE: 'K' type film caps... (0.00)
Posted by deafbykhorns on 2021-05-08, 05:06:19 (76.122.44.79)
I think Cary did the same thing with one of their 300B SET amps. .......
71: SET Asylum, RE: SS vs. Tube Preamps for SET (0.00)
Posted by deafbykhorns on 2021-04-26, 19:03:39 (76.122.44.79)
I can attest to that with my 01a preamp, used one of Dave Slagle's at the output which lowered output impedance. .......
72: SET Asylum, RE: What this Says (0.00)
Posted by deafbykhorns on 2021-04-26, 19:00:27 (76.122.44.79)
And why we purchase different interconnects when using high output impedance preamps. .......
73: SET Asylum, RE: Repaired (0.00)
Posted by deafbykhorns on 2021-04-21, 18:36:13 (76.122.44.79)
For the curious, Tom's amp had following issues 5 bad cathode resistors (parallel 620ohm) at the 845 4 resistor way out of spec (various plate and bias) Bad caps at 10v supply Some leaky cathode caps .......
74: Tube DIY Asylum, RE: Thanks! Wish I was a Real Guitar Player! (nt) (0.00)
Posted by deafbykhorns on 2021-03-04, 09:25:34 (96.94.54.195)
Just started playing myself last year at 59yrs old. Did you add tremolo, reverb? I built a 65 Fender circuit and used a alnico 10" from Jenson. It's a nice sound with some mods. Now I need to practice .......
75: SET Asylum, RE: This ^^^ (0.00)
Posted by deafbykhorns on 2021-02-12, 04:33:38 (96.94.54.195)
I have a custom SA-15 for my GM-70 (higher impedance for 1200v) and a IT-01 interstage (gapped for 50ma). I started out with some Hammond iron, the difference was night and day in terms of sound and m .......
76: SET Asylum, RE: Mojo (0.00)
Posted by deafbykhorns on 2021-02-10, 10:31:15 (96.94.54.195)
Took Mojo 8 weeks to get me just parts for a kit..... .......
77: Tube DIY Asylum, RE: Send them the good one and measure it (0.00)
Posted by deafbykhorns on 2021-02-01, 10:58:41 (96.94.54.195)
They should be able to wind one close. The core size and wire size would give them an idea of power. .......
78: Tube DIY Asylum, RE: Did you properly fuse the input supply? (0.00)
Posted by deafbykhorns on 2021-01-28, 13:17:31 (96.94.54.195)
. .......
79: SET Asylum, RE: This ^^^ (0.00)
Posted by deafbykhorns on 2021-01-05, 06:39:23 (96.94.54.195)
. .......
80: SET Asylum, RE: I live up in Jax. if you need some help (0.00)
Posted by deafbykhorns on 2021-01-05, 06:37:53 (96.94.54.195)
I have all the equipment to troubleshoot including tube testers, distortion analyzers, scope, cap testers, LCR, etc... Just turned 60 myself and do this for fun. Designed and built several amps over t .......
81: SET Asylum, RE: I live up in Jax. if you need some help (0.00)
Posted by deafbykhorns on 2021-01-04, 13:25:21 (96.94.54.195)
you can also call me at 904-three three 8 4teen seventy I do this as a hobby and would be glad to help. .......
82: Tube DIY Asylum, RE: Tube number origins (0.00)
Posted by deafbykhorns on 2020-12-08, 12:36:50 (96.94.54.195)
The first number is the "F" voltage Again, this may not always be the case .......
83: SET Asylum, RE: Yes (0.00)
Posted by deafbykhorns on 2020-10-12, 12:48:36 (96.94.54.195)
I built another amp later with the same tubes (except DRD) using Dave Slagles iron and it was night and day difference. .......
84: SET Asylum, RE: Yes (0.00)
Posted by deafbykhorns on 2020-10-09, 11:11:57 (96.94.54.195)
Didn't like the sound but it may of been the cheap iron I purchased from a guy up North off Ebay.... .......
85: SET Asylum, RE: I built these this summer (304TL) (0.00)
Posted by deafbykhorns on 2020-10-01, 16:54:09 (76.122.44.79)
I have a pair of those tube and thinking about a build. Built a GM70 pair of amps at 1150v so no stranger to HV. What kind of power are you getting in A1? What did you drive it with and whats the curr .......
86: Tube DIY Asylum, RE: Could use some help Trouble Shooting my Welborne laurel 300B Monoblock ............... (0.00)
Posted by deafbykhorns on 2020-09-01, 11:28:15 (96.94.54.195)
Check power supply caps and bypass cap for shorts Also check rectifier and OPT .......
87: Tube DIY Asylum, RE: share cad files? (0.00)
Posted by deafbykhorns on 2020-07-01, 06:28:17 (96.94.54.195)
I've got some cadd files for an amp and preamp I built if interested For Landfall, you plot as an EPS file Sharepoint link below https://netorg2082569-my.sharepoint.com/:u:/g/personal/john_munsonandbr .......
88: Tube DIY Asylum, RE: Finally Complete - 304tl (0.00)
Posted by deafbykhorns on 2020-05-31, 17:50:44 (76.122.44.79)
Nice job, any details on build posted? .......
89: Amp/Preamp Asylum, RE: Thanks for the clue (0.00)
Posted by deafbykhorns on 2020-04-23, 05:57:36 (96.94.54.195)
When you mentioned driver stage I started poking around and found the loose FET. I have never seen a socket for a TO18 type of transistor. Learn something new every day... The only protection in this .......
90: Amp/Preamp Asylum, RE: Acoustat TNT 200 amp oscillating (0.00)
Posted by deafbykhorns on 2020-04-22, 18:03:35 (76.122.44.79)
Found issue with FET drivers, i thought those were spacers under transistors, turns out they are sockets. One of the FETs came unglued and had an intermittent connection I removed socket and soldered .......
91: Amp/Preamp Asylum, Acoustat TNT 200 amp oscillating (0.00)
Posted by deafbykhorns on 2020-04-17, 14:42:55 (76.122.44.79)
Anyone have any experience with this amp oscillating? I can see it at the input and output. A 10K load and oscillation returns. I short the input and oscillation goes away. Hard to tell since it could .......
92: Inmate Central, RE: Straight Ups On This New Bug (0.00)
Posted by deafbykhorns on 2020-04-08, 13:26:30 (96.94.54.195)
It's refreshing to know there are people with some common sense in this forum. Glad you're not one of them drinking the Koolaid. Some famous quotes to ponder "The planet is fine. The people are fucke .......
93: Tube DIY Asylum, RE: Welborne Labs PS10 regulated Power Supply (0.00)
Posted by deafbykhorns on 2020-03-10, 04:51:35 (96.94.54.195)
I have used them in a 300b amp and a 01A preamp. Super quiet voltage regulator and easy to setup. You dial in the voltage range with a resistor and can fine tune the voltage with a pot which allowed m .......
94: Tube DIY Asylum, RE: Welborne Labs PS10 regulated Power Supply (0.00)
Posted by deafbykhorns on 2020-03-08, 07:33:07 (76.122.44.79)
Try this supply out, i had great results with the design. .......
95: Tube DIY Asylum, RE: Really? 126C with parallel primaries and secondaries? (0.00)
Posted by deafbykhorns on 2020-02-09, 17:02:59 (76.122.44.79)
Maybe the lower plate resistance of the 300B (JJ2A3) helped.... I later had magnequest wind me a custom choke similar to Dowdys choke, surprisingly it was just a small improvement. Ended up with a cus .......
96: Tube DIY Asylum, RE: It worked fine for me on a 300b driver to a GM70 (0.00)
Posted by deafbykhorns on 2020-02-07, 12:47:10 (96.94.54.195)
The results were better than I would expect. .......
97: Tube DIY Asylum, RE: so what am I doing wrong? (0.00)
Posted by deafbykhorns on 2020-01-26, 16:09:03 (76.122.44.79)
You still use the current device in lieu of a resistor in PSUD It more accurate .......
98: Tube DIY Asylum, RE: so what am I doing wrong? (0.00)
Posted by deafbykhorns on 2020-01-26, 05:50:23 (76.122.44.79)
.22-5uf are common in a cap input Hv supply .......
99: Tube DIY Asylum, RE: I use an AVC. nt (0.00)
Posted by deafbykhorns on 2020-01-01, 15:21:32 (76.122.44.79)
Im using Daves AVC on my preamp output with overwhelming results .......
100: Tube DIY Asylum, RE: what Tre said ^^^^^ (0.00)
Posted by deafbykhorns on 2020-01-01, 15:14:14 (76.122.44.79)
. .......
101: Tube DIY Asylum, Re Try some TVC (0.00)
Posted by deafbykhorns on 2019-12-31, 18:06:29 (76.122.44.79)
. .......
102: Tube DIY Asylum, RE: High power supply capacitance for 845 SE amp (0.00)
Posted by deafbykhorns on 2019-12-25, 06:19:40 (76.122.44.79)
I designed a similar supply around a GM70, its definitely a challenge and difficult to implement. The power supply transformer/chokes need to be over rated (at least 2X) and soft start is a must. I di .......
103: Tube DIY Asylum, RE: Audio Research Screen Regs problems (0.00)
Posted by deafbykhorns on 2019-12-09, 05:34:27 (96.94.54.195)
I have the same amp so I do know the risk. A good desoldering station will work just fine, braid not so much... .......
104: Tube DIY Asylum, RE: Audio Research Screen Regs problems (0.00)
Posted by deafbykhorns on 2019-12-08, 10:47:43 (76.122.44.79)
I assumed the OP didn't have the skills to troubleshoot... The zeners are the most common failure I have found in this amp and similar. .......
105: Tube DIY Asylum, RE: Audio Research Screen Regs problems (0.00)
Posted by deafbykhorns on 2019-12-05, 17:06:08 (76.122.44.79)
Replace all those zeners .......
106: Tube DIY Asylum, RE: My guess.. (0.00)
Posted by deafbykhorns on 2019-11-03, 17:40:28 (66.177.177.194)
Common and good practice, it will drive a nice long cable with no problem and better than cap coupling (in my opinion) I have tested this using my spectrum analyzer and found that cables effect the fr .......
107: Tube DIY Asylum, RE: My guess.. (0.00)
Posted by deafbykhorns on 2019-11-03, 09:11:04 (66.177.177.194)
Could use as Preamp opt possibly .......
108: Tube DIY Asylum, RE: Exactly (0.00)
Posted by deafbykhorns on 2019-10-28, 05:03:50 (96.94.54.195)
I have a JJ2A3- IT -GM70 using Monolith magnetics after trying 2 other methods to couple the GM70. Initially, I used a Hammond IT, which was OK but had the issues mentioned in the post. .......
109: SET Asylum, RE: Bias of Emission Labs 300B Mesh (0.00)
Posted by deafbykhorns on 2019-10-27, 07:16:23 (66.177.177.194)
I have an amp with JJ2A3 tubes that can run 40w I have them biased at 24w I tried an emission labs a few years back in the circuit and they didnt do so well at 24w, from what i remember, they red plat .......
110: Tube DIY Asylum, RE: manual for str-av460 (0.00)
Posted by deafbykhorns on 2019-10-10, 12:13:58 (96.94.54.195)
See page 20 on tape out .......
111: Tube DIY Asylum, RE: Got mine, not helping any blood sucking lawyers (0.00)
Posted by deafbykhorns on 2019-09-27, 08:18:01 (96.94.54.195)
. .......
112: Tube DIY Asylum, RE: Get a 300mA rated choke and use 0,2uf cap just before it (0.00)
Posted by deafbykhorns on 2019-09-04, 18:07:18 (66.177.177.194)
I used a 193Q, its a beast and quiet as a mouse .......
113: Tube DIY Asylum, RE: PS chokes (0.00)
Posted by deafbykhorns on 2019-08-31, 18:31:26 (66.177.177.194)
What is the load? I used one of their larger chokes in my GM70 .......
114: Tube DIY Asylum, RE: First fitting of the final components (0.00)
Posted by deafbykhorns on 2019-08-08, 16:57:31 (66.177.177.194)
Take some closeups This looks like a work of art Some nudies underneath would be nice! .......
115: Tube DIY Asylum, Cinemag (0.00)
Posted by deafbykhorns on 2019-08-08, 16:46:33 (66.177.177.194)
Looking for Cinemag sellers Emailed Cinemag directly to no avail .......
116: Tube DIY Asylum, RE: If you need the gain (0.00)
Posted by deafbykhorns on 2019-07-08, 16:56:08 (66.177.177.194)
Give it a try, my 300b amp is a 76-26-300b to one of Slagles OPT's. I have had this amp for 10 yrs and have not even considered a change. Thats after going thru many commercial amps in the past (at le .......
117: Tube DIY Asylum, RE: 21st century maida regulator (0.00)
Posted by deafbykhorns on 2019-06-28, 17:29:40 (66.177.177.194)
Yes, i have one on my 01a preamp power supply. Serves two purposes, regulation and dropping power supply voltage to dial in the 01a where it sounds best .......
118: SET Asylum, RE: Do the math (0.00)
Posted by deafbykhorns on 2019-06-07, 17:16:52 (66.177.177.194)
I'm more concerned about voltage drop from length of cable. Mine are 25' long so i use 8/4 SO cord bi-wired to deliver the current with minimal voltage drop. If your speakers are a lower impedance, th .......
119: Tube DIY Asylum, RE: Basic tube testing - questions!! (0.00)
Posted by deafbykhorns on 2019-06-05, 10:50:37 (96.94.54.195)
Why dont you throw in a cap and a speaker to check the gain and noise of each tube being tested. you can then check microphonics, gain and current draw of each tube. I simply plug them into my preamp .......
120: SET Asylum, RE: Arduino (0.00)
Posted by deafbykhorns on 2019-05-09, 17:59:30 (66.177.177.194)
I used an arduino and created a voltage divider at the cathode. The arduino is programmed to monitor the voltage and if it goes out of range, it opens the circuit to HV supply. The same arduino does m .......
121: SET Asylum, RE: Fixed Bias (0.00)
Posted by deafbykhorns on 2019-05-05, 16:55:38 (66.177.177.194)
Hopefully its not a output transformer... Try installing a 1/4amp (or less) fuse at the cathode of output tube .......
122: Tube DIY Asylum, RE: "RE: according to this they are the same thing...." That is not what that article says. (0.00)
Posted by deafbykhorns on 2019-05-05, 16:31:13 (66.177.177.194)
Hmm, i guess this is why i could never get any results when i simulated a couple yrs ago.... .......
123: Tube DIY Asylum, RE: nice little srpp se 45 amp from JE Labs (0.00)
Posted by deafbykhorns on 2019-05-05, 15:56:23 (66.177.177.194)
This was the first tube amp i ever built For me, it was "thin" and lifeless or could of been interpreted as too revealing for my horns. Maybe it was the iron or the preamp load impedance (it was low) .......
124: Tube DIY Asylum, RE: 6sn7 tubes.... (0.00)
Posted by deafbykhorns on 2019-05-01, 17:06:07 (66.177.177.194)
I would simply match tubes in pairs keeping the best and sell the remainder .......
125: Tube DIY Asylum, RE: As two... (0.00)
Posted by deafbykhorns on 2019-04-16, 11:56:17 (96.94.54.195)
Lots of Buffalonian's around here, glad I moved out of that Artic circle..... .......
126: Tube DIY Asylum, RE:they are but.... (0.00)
Posted by deafbykhorns on 2019-04-14, 13:51:12 (66.177.177.194)
Headphone jacks tap off the output via attenuation resistors usually calculated from power output of amplifier so the headphone jack doesnt exceed a voltage rating Cant read the schematic but you can .......
127: Tube DIY Asylum, RE: the new breadboard is earning its keep (0.00)
Posted by deafbykhorns on 2019-03-31, 17:01:43 (66.177.177.194)
Seems like a waste of an expensive tube for just 4 watts. Is this tube really linear at those op points? How does it compare to a 300b? .......
128: Computer Audio Asylum, USB chassis socket (0.00)
Posted by deafbykhorns on 2019-03-19, 18:38:50 (66.177.177.194)
Im having trouble sourcing a chassis socket that will hardwire to a waveio board Any ideas? .......
129: Tube DIY Asylum, RE: Dust clean-up? (0.00)
Posted by deafbykhorns on 2019-03-17, 08:16:23 (66.177.177.194)
Keep your doors closed and look into a better filtration system for your HVAC Turn on the fan while you are dusting .......
130: Tube DIY Asylum, RE: grid stoppers (0.00)
Posted by deafbykhorns on 2019-03-07, 18:20:53 (66.177.177.194)
My 01a is dead quiet as well, i put volume control at the output and used an AVC. My guess would be its in your gyrator circuit .......
131: Tube DIY Asylum, RE: The Apple Genius bar are full of (0.00)
Posted by deafbykhorns on 2019-03-01, 12:24:46 (96.94.54.195)
IDIOTS!!! .......
132: Tube DIY Asylum, RE: sorry but, Keysight is made in China too (0.00)
Posted by deafbykhorns on 2019-02-27, 16:41:51 (66.177.177.194)
. .......
133: Tube DIY Asylum, RE: Try the 300B with a good DHT (0.00)
Posted by deafbykhorns on 2019-02-25, 13:01:02 (96.94.54.195)
You don't really need much of a schematic, simply run any DHT at its op point and couple it with a cap. Here's one I did back in the day, i got about 6-8 watts depending on transformer .......
134: Tube DIY Asylum, RE: Try the 300B with a good DHT (0.00)
Posted by deafbykhorns on 2019-02-25, 07:54:02 (96.94.54.195)
If your are referring to the WE 91 you probably didn't like it because of the pentode drivers. .......
135: Tube DIY Asylum, RE: Grid Current (0.00)
Posted by deafbykhorns on 2019-02-25, 06:00:36 (96.94.54.195)
I'm not an expert in SRPP but I don't think so. It may help the output impedance and distortion but it wont provide grid current. An IT transformer or a mosfet (grid drive) would be better suited for .......
136: Tube DIY Asylum, RE: Grid Current (0.00)
Posted by deafbykhorns on 2019-02-24, 14:56:39 (66.177.177.194)
According to my simulation, your 845 is starting to pull grid current at about 3 volts output (about 1 watt) using your operating points. Your 6SN7 driver is not going to do its job alone. Your sine w .......
137: Tube DIY Asylum, RE: Sample Sine Wave (0.00)
Posted by deafbykhorns on 2019-02-23, 16:51:37 (104.238.59.147)
That top pic is pretty ugly, probably your driver giving up The sine wave should be symmetrical, whats your driver tube? .......
138: Tube DIY Asylum, RE: Sample Sine Wave (0.00)
Posted by deafbykhorns on 2019-02-22, 11:28:41 (96.94.54.195)
This is what 2.4% distortion looks like, you can see one half of the cycle is pretty flat. If you adjust the volume down just enough to make the flat part go away, your at about 1-1.5% distortion whi .......
139: Tube DIY Asylum, RE: Example (0.00)
Posted by deafbykhorns on 2019-02-21, 12:38:17 (96.94.54.195)
You measure 5 volts out when it begins to clip 5*5/8ohms=3.1 watts If you want to check freq response doing manual plots, you can do a frequency sweep starting at 5hz ending at 20K and plot it on pape .......
140: Tube DIY Asylum, RE: update 2 (0.00)
Posted by deafbykhorns on 2019-02-20, 15:15:55 (66.177.177.194)
Dont use the scope to read voltage Clip in your RMS meter and set to AC Turn up the volume until you see the sine wave start to flatten at its peaks and read the voltage. E2/R= watts .......
141: Tube DIY Asylum, RE: Melody 3 stage M845 amp (0.00)
Posted by deafbykhorns on 2019-02-20, 10:52:40 (96.94.54.195)
take a look at a GM-70, a little easier to drive. .......
142: Tube DIY Asylum, RE: Just do the math (0.00)
Posted by deafbykhorns on 2019-02-20, 06:30:22 (96.94.54.195)
Simplified version(its much more complicated under real conditions). If your body resistance is 100K(as an example) then 500v/100K=5ma Now bump it up to 800v, 800v/100K=8ma Throw in some moisture or b .......
143: Tube DIY Asylum, RE: update 2 (0.00)
Posted by deafbykhorns on 2019-02-17, 17:57:09 (66.177.177.194)
1khz sine wave at input Connect scope to output with an 8ohm load(load resistor best) Turn up input until sine wave just starts to flatten at the peaks and read the voltage, its subtle on a tube amp b .......
144: Tube DIY Asylum, RE: Question, Vinnie... (0.00)
Posted by deafbykhorns on 2019-02-17, 16:26:09 (66.177.177.194)
550v will kill you as well but if your not 100% comfortable working those voltages, stay away. And you would need to invest in better iron. .......
145: Tube DIY Asylum, RE:Pete Millet 813 (0.00)
Posted by deafbykhorns on 2019-02-17, 12:20:39 (66.177.177.194)
Pete Millet did a similar project and used 800v as an operating point. .......
146: Tube DIY Asylum, RE: update 2 (0.00)
Posted by deafbykhorns on 2019-02-17, 12:14:49 (66.177.177.194)
With all that free time, connect a scope, let it clip into an 8ohm load and read the voltage. Inquiring minds would like to know! .......
147: Tube DIY Asylum, RE: update 2 (0.00)
Posted by deafbykhorns on 2019-02-17, 03:46:40 (66.177.177.194)
What king of wattage are you getting with this setup .......
148: Tube DIY Asylum, RE: ARC VT200 reading less at the 425 vdc lines (0.00)
Posted by deafbykhorns on 2019-02-16, 05:04:15 (66.177.177.194)
Read line to line, most isolation transformers dont have a grounded nuetral. I suspect youll read about 115v under load .......
149: Tube DIY Asylum, RE: ARC VT200 reading less at the 425 vdc lines (0.00)
Posted by deafbykhorns on 2019-02-15, 17:35:34 (66.177.177.194)
Are you measuring those ac voltages to ground or line to line? .......
150: Tube DIY Asylum, RE: Probably better off with a 2A3 (0.00)
Posted by deafbykhorns on 2019-02-11, 17:29:00 (66.177.177.194)
https://www.audioasylum.com/forums/tubediy/messages/26/266586.html .......
151: Tube DIY Asylum, RE: Probably better off with a 2A3 (0.00)
Posted by deafbykhorns on 2019-02-11, 15:00:11 (66.177.177.194)
I suppose you could build a low voltage amp out any transmitting tube but it may not be linear at those voltages. That last model hardly performed up to 45/2A3 standards but kuidos to you for giving i .......
152: Tube DIY Asylum, RE: Probably better off with a 2A3 (0.00)
Posted by deafbykhorns on 2019-02-11, 07:02:36 (96.94.54.195)
The 6SN7 isn't going to drive the 845 into A2. Might sound good but seems like a lot of work(in the power supply) for 2A3 power. I would experiment with a 300B or build a 1000v supply for that tube. .......
153: Tube DIY Asylum, RE: new breadboard system up and running.... (0.00)
Posted by deafbykhorns on 2019-02-08, 04:58:43 (96.94.54.195)
Send me the schematics and I'll load them into LTspice for you. .......
154: Tube DIY Asylum, RE: new breadboard system up and running.... (0.00)
Posted by deafbykhorns on 2019-02-07, 16:54:49 (66.177.177.194)
Did you ever build his 845 amp? .......
155: Tube DIY Asylum, RE: Try Bartols's website (0.00)
Posted by deafbykhorns on 2019-02-06, 14:34:13 (66.177.177.194)
You can simply use a choke in lieu of his "gyrator" if you want. I also put my volume control at the output, this is the best way to tame those globe tubes. If you have an AVC, its even better. Very s .......
156: Tube DIY Asylum, RE: Try Bartola's website (0.00)
Posted by deafbykhorns on 2019-02-06, 14:31:28 (66.177.177.194)
You can simply use a choke in lieu of his "gyrator" if you want. I also put my volume control at the output, this is the best way to tame those globe tubes. If you have an AVC, its even better. Very s .......
157: Tube DIY Asylum, RE: new breadboard system up and running.... (0.00)
Posted by deafbykhorns on 2019-02-06, 06:25:10 (96.94.54.195)
You should try building a preamp using an 01A tube sometime, it was an eye opener for me!! .......
158: Tube DIY Asylum, RE: new breadboard system up and running.... (0.00)
Posted by deafbykhorns on 2019-02-05, 18:11:57 (66.177.177.194)
You like myself almost enjoy building more than the music itself. I cant imagine how much i might build when i retire! .......
159: Tube DIY Asylum, RE: new breadboard system up and running.... (0.00)
Posted by deafbykhorns on 2019-02-05, 17:52:08 (66.177.177.194)
Nice job! I would be comfortable to use this On a daily basis, in the garage of course .......
160: Tube DIY Asylum, RE: Do you ever listen to equipment made by other DIYers? (0.00)
Posted by deafbykhorns on 2019-02-01, 18:17:28 (66.177.177.194)
Absolutely, I have a friend that has a knack for just throwing something together without calculations and tunes it by ear. Builds some amazing equipment including dacs .......
161: Tube DIY Asylum, RE: Exactly what every tweaker-to-be wants to hear (0.00)
Posted by deafbykhorns on 2019-01-28, 06:53:19 (96.94.54.195)
amen to that .......
162: Tube DIY Asylum, RE: Now build a real triode amp (0.00)
Posted by deafbykhorns on 2019-01-27, 06:01:53 (66.177.177.194)
I discovered this triode mode about 15yrs ago on a Dynaco. I now have a GM70 pushing about 40+watts (in A2) .......
163: Tube DIY Asylum, RE: Measure the ESR and L of both (0.00)
Posted by deafbykhorns on 2019-01-23, 18:14:06 (66.177.177.194)
Might give some insight on whats going on. .......
164: Tube DIY Asylum, RE: Ebay has many listings (0.00)
Posted by deafbykhorns on 2019-01-20, 12:39:31 (104.238.59.31)
but its china sourced Standard colors .......
165: Tube DIY Asylum, RE: ARC SP6-B (0.00)
Posted by deafbykhorns on 2019-01-14, 14:54:36 (104.238.59.33)
This pre performs well with my D115 .......
166: Tube DIY Asylum, RE: Pre amp kits (0.00)
Posted by deafbykhorns on 2019-01-13, 14:27:15 (66.177.177.194)
I believe Welborne is on the DIY Audio site if you want to ask him about the boards. He may have a couple laying around .......
167: Tube DIY Asylum, RE: Sakuma-style GM-70 design - critiques please! (0.00)
Posted by deafbykhorns on 2019-01-04, 18:39:46 (66.177.177.194)
Seems like overkill to drive a gm70 with a gm70 Filament supplies are a PITA given the current, why not use a 300b. Dont bother with a plate choke, the IT works better .......
168: Tube DIY Asylum, RE: Miller Effect (0.00)
Posted by deafbykhorns on 2019-01-02, 16:10:52 (66.177.177.194)
Would an TVC work better for this scenario? Or a line xfmr from Sowter? .......
169: Amp/Preamp Asylum, RE: Or use a 4 wire ohm meter with Kelvin clips (0.00)
Posted by deafbykhorns on 2018-12-17, 05:12:42 (96.94.54.195)
. .......
170: Tube DIY Asylum, RE: That's a pretty thing (0.00)
Posted by deafbykhorns on 2018-12-13, 15:54:32 (66.177.177.194)
You can send me the Citation V to evaluate since your busy ;--) I like the block of alum slightly recessing the tubes, nice touch. Cant wait to see the finished product. .......
171: Tube DIY Asylum, RE: RoHS, more European Union tree hugging crap (0.00)
Posted by deafbykhorns on 2018-12-12, 13:15:41 (96.94.54.195)
this is why laptops and compact designs like Imac don't last. I would send off my motherboards and get the video chips re-balled using leaded solder. They last 3 times as long as the RoHS soldered chi .......
172: SET Asylum, RE: Audio Note Empress Silver Monoblocks (0.00)
Posted by deafbykhorns on 2018-12-11, 12:43:07 (96.94.54.195)
My boat anchor is much better than a couple of those you have mentioned using a GM70 tube. The JJ2A3 does well with my Khorns but the GM70 is more suited for the ribbon speakers I own. Not impressed w .......
173: Tube DIY Asylum, RE: ok, here ya go .... (0.00)
Posted by deafbykhorns on 2018-12-02, 05:22:48 (66.177.177.194)
What size resistor is that off your filament transformer? .......
174: Tube DIY Asylum, RE: without pictures (0.00)
Posted by deafbykhorns on 2018-12-01, 18:54:18 (66.177.177.194)
. .......
175: Tube DIY Asylum, RE: LTSpice (0.00)
Posted by deafbykhorns on 2018-12-01, 05:06:23 (66.177.177.194)
Its free and you can simulate the circuit at well .......
176: Tube DIY Asylum, RE: puzzled... (0.00)
Posted by deafbykhorns on 2018-11-20, 16:30:09 (66.177.177.194)
Check the resistor after the last diode .......
177: Tube DIY Asylum, RE: puzzled... (0.00)
Posted by deafbykhorns on 2018-11-19, 13:03:44 (96.94.54.195)
It's a built in time delay circuit... .......
178: Tube DIY Asylum, RE: Who's the lucky one that gets the second preamp? (0.00)
Posted by deafbykhorns on 2018-11-19, 13:00:24 (96.94.54.195)
. .......
179: Tube DIY Asylum, RE: Preamp Update (0.00)
Posted by deafbykhorns on 2018-11-18, 16:55:20 (66.177.177.194)
Did you do all the etching and drilling? If so, thats a lot of work and it looks great to boot! .......
180: SET Asylum, RE: Sweeps and bloated bass (0.00)
Posted by deafbykhorns on 2018-11-16, 11:58:10 (96.94.54.195)
I didn't have the equipment at the time to do a sweep but i knew what i was hearing was manufactured. The square wave with the hammond didnt do so good. The sweep on the Monolith Magnetics is amazing .......
181: SET Asylum, RE: Operating Point and Load impedance for GM70 (0.00)
Posted by deafbykhorns on 2018-11-15, 05:23:07 (96.94.54.195)
I'm using an 8K Monolith magnetics with a GM70. Previously used a 6.5K Hammond. The Monolith is extremely detailed and does a better job than the Hammond. The Hammond seemed to roll off but it did hav .......
182: SET Asylum, RE: I know that and .. (0.00)
Posted by deafbykhorns on 2018-11-09, 08:29:06 (96.94.54.195)
it would obviously require some changes to the circuit. Not sure if manufacture has made these changes but has mentioned the use of this tube. .......
183: Tube DIY Asylum, RE: update... (0.00)
Posted by deafbykhorns on 2018-11-08, 16:47:03 (66.177.177.194)
Could of been worse and put a low value resistor at a cathode and blow a transformer... .......
184: SET Asylum, RE: Unless its a 2A3-40W (0.00)
Posted by deafbykhorns on 2018-11-08, 10:02:20 (96.94.54.195)
which is a 300b in disguise with 2.5v filaments .......
185: Tube DIY Asylum, RE: Am I doing this right? (0.00)
Posted by deafbykhorns on 2018-11-08, 04:21:16 (96.94.54.195)
"You may have simply massively overdriven the tube." Or you have a ton of ripple in your power supply .......
186: Tube DIY Asylum, RE: Vise Brake (0.00)
Posted by deafbykhorns on 2018-11-07, 12:39:43 (96.94.54.195)
I agree, but this looks cool but might not bend the thicker aluminum without scarring it too much. I simply put the aluminum in a vice and use a hammer while applying pressure. Let us know how it work .......
187: Tube DIY Asylum, RE: need help with understanding a table (0.00)
Posted by deafbykhorns on 2018-11-04, 09:27:48 (66.177.177.194)
Power wil go up as well as distortion when primary impedance is lowered. I run mine closer to 5k but they are 2a3-40w and the transformer has much more inductance. I would experiment and see what you .......
188: Tube DIY Asylum, RE: +2 (0.00)
Posted by deafbykhorns on 2018-11-02, 05:16:32 (96.94.54.195)
I can vouch for that, my first amp used that topology and it sounded like crap (in comparison) .......
189: Tube DIY Asylum, RE: DHT AC hum noise question (0.00)
Posted by deafbykhorns on 2018-10-26, 07:39:29 (96.94.54.195)
Or use a JJ 2A3-40 (300B in disguise with 2.5v filaments) .......
190: Tube DIY Asylum, RE: Landfall systems is the bomb! (0.00)
Posted by deafbykhorns on 2018-10-09, 17:56:03 (66.177.177.194)
I simply send them a machine file exported out of autocadd and its done! The chassis build is just too painful for me. When you figure what your time is worth, the chassis from Landfall is cheap! I al .......
191: Tube DIY Asylum, RE: Do all the devices have a ground prong? (0.00)
Posted by deafbykhorns on 2018-10-05, 05:05:08 (96.94.54.195)
My be noise bleeding off the ground if you have LED lamps. If not, its the arc on the switch causing the noise. You can put a small cap across the switch or filter your power supply better. ::: TOPIC: .......
192: Tube DIY Asylum, RE: Power connector suggestions (0.00)
Posted by deafbykhorns on 2018-09-28, 14:36:56 (66.177.177.194)
It appears to be a mini xlr The pins on my sockets are not rounded of but sharper .......
193: Tube DIY Asylum, RE: Power connector suggestions (0.00)
Posted by deafbykhorns on 2018-09-27, 10:10:17 (96.94.54.195)
Yep, it appears so, wasn't aware these came in miniature versions and that someone would use one for a power connector. .......
194: Tube DIY Asylum, Power connector suggestions (0.00)
Posted by deafbykhorns on 2018-09-26, 19:07:42 (66.177.177.194)
Does anyone recognize this power connector? It has 3pins, a slot and some sort of latching mechanism(like a cam slot). The cutout hole is approx. 3/8" or more. .......
195: Tube DIY Asylum, RE: Can Im switch my 50K trimpots to 25K (0.00)
Posted by deafbykhorns on 2018-09-22, 20:11:16 (66.177.177.194)
Agreed, its unlikely that several bias pots went bad at once Start with cleaning sockets, check coupling caps next, then look at the tubes .......
196: Tube DIY Asylum, RE: Citation V Arrived (0.00)
Posted by deafbykhorns on 2018-09-22, 19:42:48 (66.177.177.194)
Keep us informed Most Ebay restorations are hack jobs. More importantly you have good transformers, cage and a decent chassis. Most the ones i see are rust buckets or selling north of 2K You got it fo .......
197: Tube DIY Asylum, RE: Change the ones near heat sources (0.00)
Posted by deafbykhorns on 2018-09-21, 18:20:36 (66.177.177.194)
. .......
198: Tube DIY Asylum, RE: Solved, I think... (0.00)
Posted by deafbykhorns on 2018-09-21, 06:00:02 (96.94.54.195)
Here's the specification I found for my HP8903 analyzer. "Analyzer input impedance 100 kΩ || 300 pF (330 pF for the OPT001)." You are correct, mu is 16 for this tube. Its double the mu of a 26 but clo .......
199: Tube DIY Asylum, RE: 845 Solen caps to Wima MKP swtich .... (0.00)
Posted by deafbykhorns on 2018-09-20, 19:10:02 (66.177.177.194)
Lots of parallel caps, are you using these in the coupling circuits? .......
200: Tube DIY Asylum, RE: The solution is another tube or (0.00)
Posted by deafbykhorns on 2018-09-20, 18:09:42 (66.177.177.194)
a lower impedance design that will drive a cable better.... This has been a great learning experience for me. My Rigol scope came with 4 probes that I don't have much faith in for precision or super h .......
201: Tube DIY Asylum, RE: HP Capacitance? (0.00)
Posted by deafbykhorns on 2018-09-20, 17:38:30 (66.177.177.194)
My meter isn't too accurate with picofarads, looking for decent LCR for the bench right that's not too pricey. Here's a couple more shots First one is 10:1 probe, varying compensation settings on prob .......
202: Tube DIY Asylum, RE: Thanks! Just ordered a pair (0.00)
Posted by deafbykhorns on 2018-09-19, 16:06:11 (66.177.177.194)
. .......
203: Tube DIY Asylum, RE: Agreed, 10m probe doesnt make a difference (0.00)
Posted by deafbykhorns on 2018-09-19, 15:59:35 (66.177.177.194)
My chinese 10:1 probes still give me horrible results. Need to dig up my HP probes... Ive heard the quote about an inch of wire but not one post has ever explained why, its all making sense now. I was .......
204: Tube DIY Asylum, RE: Cable Plots-need lower Z preamp output (0.00)
Posted by deafbykhorns on 2018-09-18, 16:01:33 (66.177.177.194)
Now I see why the cable business is thriving. Very difficult to find a cable under 20p a foot It so happens that the "Monster Cable" I was using is probably closer to 400p for a 6' piece. One thing fo .......
205: Tube DIY Asylum, RE: Dave, youre a genius! Now what? (0.00)
Posted by deafbykhorns on 2018-09-17, 15:51:12 (66.177.177.194)
Well, with an 8K resistor, it forms a perfect cutoff filter that simulates the impedance and forms a nice low pass filter. This is with using just a RCA audio cable! Tried a couple different cables an .......
206: Tube DIY Asylum, RE: RE084 Frequency response rolloff (0.00)
Posted by deafbykhorns on 2018-09-17, 07:44:23 (96.94.54.195)
No scope probe used, its connected directly to the HP8903A via BNC cables, also tried it with RCA cables via an adapter. I also used my Behringer with ARTA software using RCA cables and get the same r .......
207: Tube DIY Asylum, RE084 Frequency response rolloff (0.00)
Posted by deafbykhorns on 2018-09-16, 16:22:49 (66.177.177.194)
Helping a friend diagnose high freq roll off on a simple Preamp. **Choke loaded **Coleman filament supply with a ton of bypass capacitance (was advised by another builder) **150volts at anode with 4ma .......
208: Tube DIY Asylum, RE: Citation V Q. (0.00)
Posted by deafbykhorns on 2018-09-14, 13:00:00 (96.94.54.195)
What steered you to the Citation V? Transformers? I have owned the Marantz 8b amps but wasn't impressed by them. From what I remember when I was buying and selling amps, those tubes are driven hard. : .......
209: Tube DIY Asylum, RE:you could build something better (0.00)
Posted by deafbykhorns on 2018-09-04, 18:11:56 (66.177.177.194)
Dont waste your money .......
210: Tube DIY Asylum, Test bench- Meter suggestions (0.00)
Posted by deafbykhorns on 2018-08-31, 16:54:57 (66.177.177.194)
Finally got around to rearranging my test bench and building a breakout box to make testing easier. Added a 1meg, 10meg and 10k variable input/output jacks with compensation. I have an HP Analyzer, B& .......
211: Tube DIY Asylum, RE: DIY Project idea's (0.00)
Posted by deafbykhorns on 2018-08-06, 12:45:25 (96.94.54.195)
Thanks! That's good to hear, never thought about capacitance with the ground plane. Using MU-metal does a great job of isolating power supply noise, my preamp is dead quiet using this method. I assume .......
212: Tube DIY Asylum, DIY Project idea's (0.00)
Posted by deafbykhorns on 2018-08-06, 08:06:56 (96.94.54.195)
Well, now that I have completed my amp, turntable and preamp project, I need some ideas on a couple source component projects. I have a nice Vinyl One phono preamp and wondering if I could build somet .......
213: Tube DIY Asylum, RE: Your wife created a router schedule to shut you down (0.00)
Posted by deafbykhorns on 2018-08-02, 16:31:51 (66.177.177.194)
kidding aside, could be an ISP issue .......
214: Tube DIY Asylum, RE: The SP6 reminds me of a decent SS preamp (NT) (0.00)
Posted by deafbykhorns on 2018-08-02, 10:41:03 (96.94.54.195)
. .......
215: Tube DIY Asylum, RE: Preamp 100% with AVC (0.00)
Posted by deafbykhorns on 2018-08-02, 06:25:36 (96.94.54.195)
I'm about 12 hours east of Houston in Jacksonville Beach.... The comparison was a 50K resistive input pot at the grid vs. an AVC on the output (removing the input pot). I'm guessing my normal listenin .......
216: Tube DIY Asylum, RE: This is what it looks like on paper (0.00)
Posted by deafbykhorns on 2018-08-01, 13:27:41 (96.94.54.195)
Disregard the notch filter I was playing with... My speakers nor most music material doesn't go low enough to worry about the inductance in the AVC. Graph using 1u,1.5u or 2.2u coupling cap ::: .......
217: Tube DIY Asylum, RE: Preamp 100% with AVC (0.00)
Posted by deafbykhorns on 2018-08-01, 13:17:36 (96.94.54.195)
Just telling you what I was told from someone who used to communicate with him periodically. I don't know the specifics of the conversation. Not sure why you mentioned RIAA.... I just pointed out that .......
218: Tube DIY Asylum, RE: Preamp 100% with AVC (0.00)
Posted by deafbykhorns on 2018-08-01, 13:10:54 (96.94.54.195)
I really believe it's the low Z at the output... Most AVC's max out at 8volts however, most amps have full output at 1-2.5volts so unless you have a two stage amp without enough voltage gain, the AVC .......
219: Tube DIY Asylum, RE: No, AVC is not output Tx (0.00)
Posted by deafbykhorns on 2018-08-01, 12:58:42 (96.94.54.195)
Maximum voltage on most AVC's are about 8v I don't think you can use an AVC as an output transformer since the windings are common to the primary on an autoformer. I guess a TVC as an output would bas .......
220: Tube DIY Asylum, RE: Preamp 100% with AVC (0.00)
Posted by deafbykhorns on 2018-07-31, 18:24:20 (66.177.177.194)
Source-preamp-amp connections are hardly ever ideal including MC step-ups, etc. But when you DIY, simulate and source custom trannys, its certainly a good possibility you can get it right. I think the .......
221: Tube DIY Asylum, RE: Preamp 100% with AVC (0.00)
Posted by deafbykhorns on 2018-07-31, 18:08:00 (66.177.177.194)
Heres a previous post with the restive pot on the input which was replaced with the AVC. See link below .......
222: Tube DIY Asylum, Preamp 100% with AVC (0.00)
Posted by deafbykhorns on 2018-07-31, 16:22:22 (66.177.177.194)
Holy shit! Dave's AVC on the output was the finishing touch and put this Liinestage to new levels! The 01a has plenty of current to drive the AVC despite some feedback from other members. Need to t .......
223: SET Asylum, RE:Intact Audio (0.00)
Posted by deafbykhorns on 2018-07-28, 20:34:01 (66.177.177.194)
Dave builds a really nice OPT that will take it to another level. Been there, done that with some of the other brands... .......
224: Tube DIY Asylum, RE: It's a work of Dave, actually,... (0.00)
Posted by deafbykhorns on 2018-07-23, 18:00:51 (66.177.177.194)
Definately a dying art, glad we have people like Dave willing to keep it going. I have Dave's OPTs on my flea amps and it smokes every other transformer i have tried to date. Worth every penny! Got th .......
225: Tube DIY Asylum, RE: Update- Intact Audio AVC arrived (0.00)
Posted by deafbykhorns on 2018-07-23, 11:52:09 (96.94.54.195)
Its a work of art .......
226: Tube DIY Asylum, RE: I need slightly more gain and (0.00)
Posted by deafbykhorns on 2018-07-20, 10:02:07 (96.94.54.195)
with a choke or gyrator, you can achieve maximum gain. I need it more so for my phono stage and to drive my "boat anchor" amplifier since the first stage is eventually going to be an 801A. I was think .......
227: Tube DIY Asylum, Preamp 99% Complete (0.00)
Posted by deafbykhorns on 2018-07-19, 17:24:31 (66.177.177.194)
I finally completed my preamp to match the GM70 monoblocks after taking a break from audio for a year. This 01A is a beautiful sounding preamp but very difficult to keep quiet. Circuit consists of a .......
228: Tube DIY Asylum, RE: 304tl (0.00)
Posted by deafbykhorns on 2018-07-15, 10:03:53 (66.177.177.194)
Thats a heck of a power supply for a filament. I might need to rethink ever building with one of these tubes unless i move up to N.C. .......
229: Tube DIY Asylum, RE: 304tl (0.00)
Posted by deafbykhorns on 2018-07-14, 18:59:58 (66.177.177.194)
Heres one next to my gm70 I have a couple that i might use one day The filiment supply is ridiculous at 12 amps .......
230: Tube DIY Asylum, RE: 833a amp with some big iron (0.00)
Posted by deafbykhorns on 2018-07-14, 18:47:46 (66.177.177.194)
Not really, the hard part is the power supply With a mu of 35, you can drive it with a current source triode .......
231: Tube DIY Asylum, RE: 833a amp with some big iron (0.00)
Posted by deafbykhorns on 2018-07-13, 17:46:26 (66.177.177.194)
. .......
232: Shady Lane, RE: His IP is registered about 3 miles from my office (nt) (0.00)
Posted by deafbykhorns on 2018-07-12, 05:53:44 (96.94.54.195)
NT .......
233: Tube DIY Asylum, RE: +1 (0.00)
Posted by deafbykhorns on 2018-07-09, 18:13:55 (66.177.177.194)
Unfortunately you cant hardly purchase anything not made overseas. We did a contracting job under the Buy American act and it was almost impossible to source the products in the US. Some of the factor .......
234: Tube DIY Asylum, RE: why I dont use Ebay for new parts (0.00)
Posted by deafbykhorns on 2018-07-09, 07:02:41 (96.94.54.195)
same thing happened to me a couple times. Unfortunately, Ebay has become the "Walmart" for sourcing any new parts. I avoid at all costs if I can and only source unobtanium and used parts. Hell, I cant .......
235: Tube DIY Asylum, RE: Preamp done but.... (0.00)
Posted by deafbykhorns on 2018-07-01, 16:41:04 (104.207.76.64)
And how will putting the pot on the output change the microphonics? Its noisy at low or higher gain .......
236: Tube DIY Asylum, Preamp done but.... (0.00)
Posted by deafbykhorns on 2018-07-01, 13:26:58 (104.207.76.64)
Couple issues Used a cheap Ebay stepped attenuator and its very noisy (mechanically). Its been so long since i used one but i recall them being quieter mechanically. Thinking about using a regular Pot .......
237: Tube DIY Asylum, RE: Super nice job! (0.00)
Posted by deafbykhorns on 2018-06-29, 04:51:07 (96.94.54.195)
Gun is between 600-800 depending on what I'm soldering. I like to get the heat off the device as quick as I can. .......
238: Tubes Asylum, RE: Which would sound better driving a DC coupled 2A3,a Single or a Paralelled section 6SN7 triode, (0.00)
Posted by deafbykhorns on 2018-06-28, 08:24:36 (96.94.54.195)
I don't think you will get more gain. The cathode cap needs to be removed if you parallel from what I remember or the impedance goes up. It will give you more current to drive the tube, it certainly w .......
239: Tube DIY Asylum, RE: Matching amps (0.00)
Posted by deafbykhorns on 2018-06-27, 18:46:17 (66.177.177.194)
Hammond IT was swapped for a monolith magnetics tranny as well as the OPT .. .......
240: Tube DIY Asylum, Preamp almost complete (0.00)
Posted by deafbykhorns on 2018-06-27, 17:44:30 (96.94.54.195)
This has got to be my slowest project in history. I built my GM70 amp in 3 months, been working on the preamp since August last year. After reading about some of the other projects, i got motivated la .......
241: Tube DIY Asylum, RE: Protection circuit (0.00)
Posted by deafbykhorns on 2018-06-27, 04:46:54 (96.94.54.195)
Wow, I probably troubleshooted many amps using this chip.... Never looked into its functions. Perfect for your application with the built in offset function, delay, overload and AC detection. You must .......
242: Tube DIY Asylum, RE: Protection circuit (0.00)
Posted by deafbykhorns on 2018-06-26, 17:24:00 (66.177.177.194)
Did you do some PIC programming on your protection circuits? For me, i found the arduino to be the easiest to program and implement I cant wait to see the finished product! Wished i lived close by, wo .......
243: Tube DIY Asylum, RE: coming full circle with a nice beginners project amp (0.00)
Posted by deafbykhorns on 2018-06-24, 17:48:30 (66.177.177.194)
That topology is the basis of many designs, you could build just about anything with many different tubes .......
244: Tube DIY Asylum, RE: Very cool... (0.00)
Posted by deafbykhorns on 2018-06-24, 17:27:13 (66.177.177.194)
So the opamp varys the bias so theres 0 offset voltage? Its a little over my head but thats a guess. And how do you protect the output of preamp if the opamp fails? In TK fashion, its the typical cath .......
245: Tube DIY Asylum, RE: Preamp Progress (0.00)
Posted by deafbykhorns on 2018-06-24, 07:00:31 (66.177.177.194)
Very nice! Any details to come about your design? Interested how you implemented the output without any coupling cap/transformer .......
246: Tubes Asylum, RE: so........ (0.00)
Posted by deafbykhorns on 2018-06-20, 16:48:11 (66.177.177.194)
The tubes need to be matched, hence the single pot. One might be out of whack .......
247: Tube DIY Asylum, RE: Speaker Impedance Selector (0.00)
Posted by deafbykhorns on 2018-06-17, 17:41:04 (66.177.177.194)
Unless you are marketing the amp, simply use what matches your speakers. I own 104dbw and 90dbw speakers, both perform best at 8 ohms .......
248: Tube DIY Asylum, RE: Surprised you haven't seen this before (0.00)
Posted by deafbykhorns on 2018-06-13, 17:22:17 (96.94.54.195)
Never trust continuity as a valid test, load will open a poor connection no matter how small. I always test with a load, components can react the same way with voltage applied. I have tested transisto .......
249: Tube DIY Asylum, RE: 2nd schematic lacks a ground on signal ckt (0.00)
Posted by deafbykhorns on 2018-06-12, 16:01:19 (66.177.177.194)
Other than that, its ok Vinnie, i would start over, try following my diagram and highlight each connection as you make a solder joint. Its easy to lose track with our aging minds. .......
250: Tube DIY Asylum, RE: update 4 (0.00)
Posted by deafbykhorns on 2018-06-12, 12:49:40 (96.94.54.195)
I was about to ask about the grounds The voltage he was specifying was telling me cathode is floating above ground. .......
251: Tube DIY Asylum, RE: Take out the hum pot and check it (0.00)
Posted by deafbykhorns on 2018-06-11, 12:39:08 (96.94.54.195)
. .......
252: Tube DIY Asylum, RE: update 2 (0.00)
Posted by deafbykhorns on 2018-06-11, 11:22:02 (96.94.54.195)
This circuit is simple and it works according to Spice and my general calculations. I would take it apart and start over. It's actually the front end circuit to one of Cary Audio's transmitting triode .......
253: Tube DIY Asylum, RE: update 2 (0.00)
Posted by deafbykhorns on 2018-06-11, 08:02:57 (96.94.54.195)
I don't think so, B+ would be much higher at 2.7K resistor It should be closer to 27K to get the B+ in range of the schematic or does that say 199v at the plate? I would be closer to 187v if using tha .......
254: Tube DIY Asylum, RE: update 2 (0.00)
Posted by deafbykhorns on 2018-06-11, 07:54:53 (96.94.54.195)
Power output is better at 820ohm cathode but you are running the tube above maximum output. I would use a JJ2A3 since it would handle this current but you would need to run the plate voltage much high .......
255: Tube DIY Asylum, RE: update 2 (0.00)
Posted by deafbykhorns on 2018-06-11, 07:36:54 (96.94.54.195)
This is what Spice says it should read for voltages I modeled with 1.5K and 820 ohm cathode resistors. See additional voltages at the plate of driver .......
256: Tube DIY Asylum, RE: puzzled once again... (0.00)
Posted by deafbykhorns on 2018-06-10, 07:09:57 (66.177.177.194)
crossed up wiring to socket pins? You may not have a tracer but use your volt meter and check for the obvious .......
257: Tube DIY Asylum, RE: Preamp Preview (0.00)
Posted by deafbykhorns on 2018-04-21, 15:27:39 (66.177.177.194)
I sinked the coleman supplies and coupled the Cathode R with a small block (started with just the 1/8" alum chassis and it got too hot over time) .......
258: Tube DIY Asylum, RE: Preamp Preview (0.00)
Posted by deafbykhorns on 2018-04-20, 13:01:32 (96.94.54.195)
In this case, I would use a thick piece of alum to couple the two .......
259: Tube DIY Asylum, RE: Chassis is Aluminum (0.00)
Posted by deafbykhorns on 2018-04-20, 13:00:15 (96.94.54.195)
It makes a great sink and worked well in my GM70 amps .......
260: Tube DIY Asylum, RE: Filament Bias resistors (0.00)
Posted by deafbykhorns on 2018-04-20, 12:58:41 (96.94.54.195)
. .......
261: Tube DIY Asylum, RE: Preamp Preview (0.00)
Posted by deafbykhorns on 2018-04-17, 16:12:35 (66.177.177.194)
I only used a grommet, this transformer is less than 300v to ground unlike the boat anchor i built. .......
262: Tube DIY Asylum, Preamp Preview (0.00)
Posted by deafbykhorns on 2018-04-16, 16:21:09 (66.177.177.194)
I don't know if any of you guys remember but I built a couple boat anchors last year and now working on the matching preamp. Here's a quick preview of my layout. CNC went well on chassis except for m .......
263: Tube DIY Asylum, RE: "IMO, it's not specifically made in China that is the problem." (0.00)
Posted by deafbykhorns on 2018-04-13, 12:55:55 (96.94.54.195)
I agree with everything you say but they use another method of bribery in the US (payoff's, vacations, earmarks,etc..), I don't really see a difference, forced or not. It's difficult not to purchase s .......
264: Tube DIY Asylum, RE: Dont bother (0.00)
Posted by deafbykhorns on 2018-03-18, 18:18:14 (66.177.177.194)
I would call Jack Eliano, Dave Slagle or Mike for a much better transformer Been there done that! .......
265: Tube DIY Asylum, RE: Chop saw (0.00)
Posted by deafbykhorns on 2017-12-13, 19:40:31 (66.177.177.194)
. .......
266: Tube DIY Asylum, RE: I like my Maxis punch even better (0.00)
Posted by deafbykhorns on 2017-12-11, 17:11:41 (66.177.177.194)
If you do a lot of chassis work, this will make it easy .......
267: SET Asylum, RE: GM-70 (0.00)
Posted by deafbykhorns on 2017-12-03, 10:32:27 (66.177.177.194)
Go with the GM70 It's cheaper, easier to drive and sounds pretty darn good with the right iron If your comfortable with 1kv+ and need the power, go for it. .......
268: Tube DIY Asylum, RE: Preamp Project: Chassis and Sub-Panel (photos) (0.00)
Posted by deafbykhorns on 2017-11-27, 13:29:41 (66.177.177.194)
Nice work! They could easily update the software and move threads to the top after an updated post. This software is probably 15yrs old or more. .......
269: Tubes Asylum, Re: it is a 300b with 2.5v filaments (0.00)
Posted by deafbykhorns on 2017-11-22, 16:35:51 (66.177.177.194)
It's one of my favorite tubes. .......
270: Tube DIY Asylum, RE: Thread the panel and (0.00)
Posted by deafbykhorns on 2017-11-21, 14:57:05 (45.56.149.6)
use a jamb nut on the backside .......
271: Tube DIY Asylum, RE: I called Hammond when building my GM70 (0.00)
Posted by deafbykhorns on 2017-11-20, 04:40:10 (96.94.54.195)
They told me running them at 1000v would not be a problem as well. I ran the amps at 1100v for a year before moving up. .......
272: Tubes Asylum, Re: try JJ 40w 2a3 (0.00)
Posted by deafbykhorns on 2017-11-18, 14:49:04 (174.227.140.139)
Mine have been going strong for 5 years .......
273: Tube DIY Asylum, RE: Has anyone tried the hammond 1638SEA 211se trans? (0.00)
Posted by deafbykhorns on 2017-11-17, 07:40:27 (96.94.54.195)
Not a bad transformer, I could certainly live with it, has good bass and decent high end, but not the detail I get from the Monolith Magnetics. It measures well and has a decent square wave for the mo .......
274: Tube DIY Asylum, RE: Old cap?. (0.00)
Posted by deafbykhorns on 2017-11-07, 17:10:37 (66.177.177.194)
. .......
275: Tube DIY Asylum, RE: Built myself a 26 line stage (0.00)
Posted by deafbykhorns on 2017-11-07, 17:02:48 (66.177.177.194)
Kin to a choke as it try's to emulate one .......
276: Tube DIY Asylum, RE: nice little 300B (0.00)
Posted by deafbykhorns on 2017-11-01, 15:45:20 (66.177.177.194)
Did you ever download those spice files I sent you? It's all there .......
277: Tube DIY Asylum, RE: nice little 300B (0.00)
Posted by deafbykhorns on 2017-11-01, 08:05:52 (96.94.54.195)
I built a 76-26-300B(JJ2A3), all cap coupled to a Slagle 5k for lower THD. It drives my KHorns and sounds better than the last 50-75 commercial amps I've owned. If you have a preamp with some drive, g .......
278: Tube DIY Asylum, RE: my copper chassis (0.00)
Posted by deafbykhorns on 2017-10-19, 19:41:54 (66.177.177.194)
Cant remember the wax I used but I after 5years it still looks great .......
279: Tube DIY Asylum, RE: Preamp Part 5-Chassis design (0.00)
Posted by deafbykhorns on 2017-10-17, 12:41:30 (96.94.54.195)
I have some ST versions that may do better as well as a 112. I did breadboard but not with all the chokes, used a DC power supply... The 01A is very microphonic, I think the CCS and the extra gain mak .......
280: Tube DIY Asylum, RE: it's usually my lack of seeing or proof reading (0.00)
Posted by deafbykhorns on 2017-10-16, 16:47:19 (66.177.177.194)
And Too lazy to get those reading glasses .......
281: Tube DIY Asylum, RE: Not sure 250v would give that magical glow (0.00)
Posted by deafbykhorns on 2017-10-16, 14:54:21 (66.177.177.194)
That's the point, we can pull them out of our amps if we need them in our tester! .......
282: Tube DIY Asylum, RE: Not sure 250v would give that magical glow (0.00)
Posted by deafbykhorns on 2017-10-16, 10:34:58 (96.94.54.195)
Would be overkill for a preamp as well. Thought about converting my GM70 amps, currently have 2-6ax4 tubes and its connected to an arduino with about a 90 second delay. 1100volt would surely give a li .......
283: Tube DIY Asylum, RE: Preamp Part 5-Chassis design (0.00)
Posted by deafbykhorns on 2017-10-16, 08:18:05 (96.94.54.195)
Yep, I decided to try old school tubes mixed in with some new school voltage regulation. If it sucks, I have a backup plan utilizing the same chassis, power supply, etc using a low Rp tube in a cathod .......
284: Tube DIY Asylum, Preamp Part 5-Chassis design (0.00)
Posted by deafbykhorns on 2017-10-15, 16:06:15 (66.177.177.194)
Attached my initial layout of chassis. Going to use the same guys that did my GM70 amps (Landfall Systems). Wish I had access to a CNC but I don't enjoy drilling holes, besides, I can't properly mill .......
285: Tube DIY Asylum, RE:Use an autoformer (0.00)
Posted by deafbykhorns on 2017-10-15, 06:58:06 (66.177.177.194)
These can be used in front of primary and are much smaller since they don't carry the entire load. A simple 120-12/24 or 16/32 could be used to "buck" to voltage .......
286: Tube DIY Asylum, RE: Change the old caps if.... (0.00)
Posted by deafbykhorns on 2017-10-13, 06:42:03 (96.94.54.195)
you don't care about resale value. Also check those old carbon resistors, you'll find them to be way out of tolerance, the 12au7 phase splitter will perform better with new resistors.... I did a rebui .......
287: Tube DIY Asylum, RE: Preamp Project - Preliminary Block Diagram (0.00)
Posted by deafbykhorns on 2017-10-11, 10:01:25 (96.94.54.195)
Would the output impedance be low enough with direct coupled cathode-follower? Plate resistance in the 9Kish range? .......
288: Tube DIY Asylum, RE: Preamp Project - Preliminary Block Diagram (0.00)
Posted by deafbykhorns on 2017-10-11, 05:08:13 (96.94.54.195)
What is the anticipated gain of your preamp? Is the servo for some kind of DC offset? .......
289: Tube DIY Asylum, RE: 6SN7 Crosstalk (0.00)
Posted by deafbykhorns on 2017-10-09, 08:04:34 (96.94.54.195)
he triode amplifier circuits used for all tubes were based on the resistance-coupled amplifier circuits in the RCA Receiving Tube Manual where Ebb=180V and Rp=47kohm. A sine wave generator was used f .......
290: Tube DIY Asylum, RE: Can that be posted here? (0.00)
Posted by deafbykhorns on 2017-10-08, 19:33:20 (66.177.177.194)
Attached results .......
291: Tube DIY Asylum, RE: Transformer ratio (0.00)
Posted by deafbykhorns on 2017-10-08, 13:11:08 (66.177.177.194)
I guess for modeling purposes, just go high and trust the transformer winder will do a good job of winding something that works with your project? Most winders only want the impedance and current, so .......
292: Tube DIY Asylum, RE: Transformer ratio (0.00)
Posted by deafbykhorns on 2017-10-08, 04:33:17 (66.177.177.194)
What is the formula used to calculate .32H from Freq and impedance. .......
293: Tube DIY Asylum, Transformer ratio (0.00)
Posted by deafbykhorns on 2017-10-07, 13:45:21 (66.177.177.194)
Is there a method to solving ratio and inductance with only impedance data? Say its 20K:600 transformer gaped for about 10ma What would one use in spice for inductance and/or ratio .......
294: Tube DIY Asylum, RE: Resistor Material Differences (0.00)
Posted by deafbykhorns on 2017-10-07, 03:38:07 (66.177.177.194)
The SP3,It's all internet hype to drive up prices, noisy switches, crosstalk...it's nothing more than a souped-up Dynaco. The SP6 is a much better preamp, I still use mine to this day. And will contin .......
295: Tube DIY Asylum, RE: I'm being baited now? Is this an audio or PMS forum? (0.00)
Posted by deafbykhorns on 2017-10-03, 11:20:06 (96.94.54.195)
I get enough of this at home! How do we know what is true from the past? Wasn't Tesla and others employee's of Edison? It's pretty much how it works today. I don't know what to believe and certainly d .......
296: Tube DIY Asylum, RE: Potentiometers (0.00)
Posted by deafbykhorns on 2017-10-02, 15:57:51 (66.177.177.194)
Just ordered a taiwan 23 stepped with KOA carbon resistors. I know how you feel about chinese but I feel better about using a Taiwan product (unless its complete BS). Would really like to try one of t .......
297: Tube DIY Asylum, RE: ?? (0.00)
Posted by deafbykhorns on 2017-10-02, 15:46:06 (66.177.177.194)
I had the negative from the coleman connected directly to the filament and the resistor going to ground like a cathode bias scheme. In filament bias, the coleman negative gets grounded and resistor is .......
298: Tube DIY Asylum, RE: I'm an idiot.... (0.00)
Posted by deafbykhorns on 2017-10-02, 15:07:07 (66.177.177.194)
Ok, I'm officially a dumb a$%.... I had the ground wire on the wrong side of filament resistor. I feel like an idiot! I guess sometimes you look beyond the obvious, just wasn't familiar with filament .......
299: Tube DIY Asylum, RE: Maybe my tubes are a little different? (0.00)
Posted by deafbykhorns on 2017-10-02, 11:26:43 (96.94.54.195)
4 volts seems a little low according to the plate curves but 65v at the anode would suggest the plate current is much higher. Im starting to think that the voltage at the filament of tube is not as im .......
300: Tube DIY Asylum, RE: See DIY Audio (0.00)
Posted by deafbykhorns on 2017-10-02, 11:06:57 (96.94.54.195)
See schematic of Gyrator, I tried this with a plate choke and got the same results so it must be the filament bias driving the current? 65v at 3ma is not an ideal place to be according to plate curve .......
301: Tube DIY Asylum, RE: Filament Bias (0.00)
Posted by deafbykhorns on 2017-10-02, 05:48:52 (96.94.54.195)
The gyrator is working as I can set voltage/current at the anode. But, the anode voltage has to be dialed down to 65v to achieve 3ma. I guess my question is, does the filament bias have anything to do .......
302: Tube DIY Asylum, Filament Bias (0.00)
Posted by deafbykhorns on 2017-10-01, 16:54:29 (66.177.177.194)
I'm new to this bias scheme and can't seem to find the answers. The schematic below works fine as biased, voltages about right. When I filament bias with approx 15volts and a 20ohm resistor, I need to .......
303: Tube DIY Asylum, RE: No problems here (0.00)
Posted by deafbykhorns on 2017-09-30, 08:11:28 (66.177.177.194)
.. .......
304: Tube DIY Asylum, RE: Preamp Part 4-phono (0.00)
Posted by deafbykhorns on 2017-09-29, 19:27:45 (66.177.177.194)
Yeah, I was thinking can of worms.... But thought it might be nice, I use this system mostly with CD or computer audio input and thought it would be nice to have the option .......
305: Tube DIY Asylum, Preamp Part 4-phono (0.00)
Posted by deafbykhorns on 2017-09-29, 18:15:37 (66.177.177.194)
Gathering parts, assembled HV regulators, Colemans and some of Ales gyrator boards for testing. I'm going to breadboard gyrator, plate choke and line output transformer before deciding on final layout .......
306: Tube DIY Asylum, RE: Thomas Edison... (0.00)
Posted by deafbykhorns on 2017-09-29, 17:54:44 (66.177.177.194)
Thomas Edison's teachers said he was "too stupid to learn anything." He was fired from his first two jobs for being "non-productive." As an inventor, Edison made 1,000 unsuccessful attempts at inventi .......
307: Tube DIY Asylum, RE: Link sent (0.00)
Posted by deafbykhorns on 2017-09-28, 11:29:35 (96.94.54.195)
You should have access and be able to right click and download. Once you download, copy the directory to your drive and execute scad3.exe from the LTspiceIV subfolder. Move the Schematics to the LTSpi .......
308: Tube DIY Asylum, RE: Spice does not bypass theory! (0.00)
Posted by deafbykhorns on 2017-09-28, 11:22:17 (96.94.54.195)
Correct, but you can study other schematics and use similar circuits to inject in your circuit to get these ballparks. Once you do that, its a matter of tweaking the values until you find the results. .......
309: Tube DIY Asylum, RE: Send me your email thru the PM system (0.00)
Posted by deafbykhorns on 2017-09-28, 10:55:01 (96.94.54.195)
. .......
310: Tube DIY Asylum, RE: "Sharing is caring" (0.00)
Posted by deafbykhorns on 2017-09-28, 07:59:16 (96.94.54.195)
Send me your email address in a PM .......
311: Tube DIY Asylum, RE: try LTSpice (0.00)
Posted by deafbykhorns on 2017-09-28, 05:12:35 (96.94.54.195)
I learned it in one night. For me, it's a lazy way of experimenting without doing the math by hand or picking up a book. And will answer a lot of these questions. I simply experiment with values until .......
312: Tube DIY Asylum, RE: Have you had your hearing checked? (0.00)
Posted by deafbykhorns on 2017-09-27, 05:05:37 (96.94.54.195)
Don't take this the wrong way but you may have some hearing loss. Or maybe you have a very "live" listening area that boosts some frequencies. Concrete or tile floors can do this as well. Do a frequen .......
313: MagneQuest/Peerless Forum, Dowdy choke (0.00)
Posted by deafbykhorns on 2017-09-25, 11:01:32 (96.94.54.195)
Can your Dowdy choke be re-purposed (regapped) for about 6-10ma? Need some high inductance for a 01A tube preamp I'm experimenting with. .......
314: Tube DIY Asylum, RE: ...Very nice! (0.00)
Posted by deafbykhorns on 2017-09-23, 04:35:12 (66.177.177.194)
Can you describe the build .......
315: Tube DIY Asylum, RE: LTSpice model 274B (0.00)
Posted by deafbykhorns on 2017-09-20, 18:59:14 (66.177.177.194)
How's this look? Should give plenty of separation... The inductor input should be a plus .......
316: Tube DIY Asylum, RE: I don't do ugly.... (0.00)
Posted by deafbykhorns on 2017-09-20, 18:03:30 (66.177.177.194)
Thanks for the idea Here's the DIY amp I'm driving. Have made several changes since like replacing the Hammond IT for Monolith Magnetics .......
317: Tube DIY Asylum, Preamp Part 3- power supply (0.00)
Posted by deafbykhorns on 2017-09-20, 15:42:57 (66.177.177.194)
Working on design and acquiring parts for power supply for 301a preamp(see previous part 1&2). Parts already in route for filament supplies and chassis HV. I'm not well versed on the different rectifi .......
318: Tube DIY Asylum, RE: This guy is awesome (0.00)
Posted by deafbykhorns on 2017-09-18, 18:06:56 (66.177.177.194)
Is he on this forum? .......
319: Tube DIY Asylum, RE: This guy is awesome (0.00)
Posted by deafbykhorns on 2017-09-18, 16:23:42 (66.177.177.194)
Check out some his other videos as well. He does a great job explaining things .......
320: Tube DIY Asylum, RE: MA rating would be a guess unless (0.00)
Posted by deafbykhorns on 2017-09-18, 11:26:44 (96.94.54.195)
you have a scope and can test saturation. .......
321: Tube DIY Asylum, RE: my globes always seem to be noisier (0.00)
Posted by deafbykhorns on 2017-09-17, 13:24:45 (174.227.6.189)
my globes always seemed to be noisier and microphonic .......
322: Tube DIY Asylum, RE: Are we done yet? (0.00)
Posted by deafbykhorns on 2017-09-15, 16:16:55 (66.177.177.194)
All people are "wired" differently like the amps that we build on this forum. Can we/you simply all get along and not get offended by these trivial arguments. One thing I've learned since the computer .......
323: Tube DIY Asylum, RE: Found some good 6n1p's at a good price on ebay.... (0.00)
Posted by deafbykhorns on 2017-09-14, 16:37:10 (66.177.177.194)
At a minimum you can post the user name but have seen others post links. i didn't see anything in the rules that jumped out at me .......
324: Tube DIY Asylum, RE: Found some good 6n1p's at a good price on ebay.... (0.00)
Posted by deafbykhorns on 2017-09-14, 16:16:53 (66.177.177.194)
Care to share sellers info? .......
325: Tube DIY Asylum, RE: Can't we all just get along? (0.00)
Posted by deafbykhorns on 2017-09-14, 13:06:23 (96.94.54.195)
Simple human errors on electrical plans are usually typo error's. A typo error on a civil drawing can be a costly mistake.... Electrical plans are just a schematic guideline, installations always vary .......
326: Tube DIY Asylum, RE: Can't we all just get along? (0.00)
Posted by deafbykhorns on 2017-09-14, 12:50:54 (96.94.54.195)
Being an electrical contractor and design firm I see more dumb shit field mistakes than bad engineering designs...I see less from those that went thru apprenticeship to get a proper education so Gusse .......
327: Tube DIY Asylum, RE: Who has the closed mind? (0.00)
Posted by deafbykhorns on 2017-09-14, 11:29:14 (96.94.54.195)
The way you build in my view is similar to bread boarding. You're constantly re-purposing chassis's so I see your point, take the easy route and see what happens, I get it. I finished a boat anchor la .......
328: Tube DIY Asylum, RE: I like a little hum too... (0.00)
Posted by deafbykhorns on 2017-09-13, 18:38:54 (66.177.177.194)
But in the right place like a 2A3 .......
329: Tube DIY Asylum, RE: Rod Coleman regulator (0.00)
Posted by deafbykhorns on 2017-09-13, 10:45:35 (96.94.54.195)
This is the best way I have found to heat these tubes. You'll never get rid of the hum with conventional AC heating .......
330: Tube DIY Asylum, RE: Hurricane Irma cleanup but thanks for all suggestions (0.00)
Posted by deafbykhorns on 2017-09-11, 17:54:07 (66.177.177.194)
Andy, I don't need it as a driver since my amp has plenty of juice. Just want to have a slight voltage gain without worrying about cables. What kind of inductance did you need to get a decent freq res .......
331: Tube DIY Asylum, Preamp project part 3-final tube selection (0.00)
Posted by deafbykhorns on 2017-09-10, 19:03:49 (66.177.177.194)
After much research, I will start experimenting with the 01a and 12a tube. Anyone have experience with this tube? Line OPT, parafeed, plate choke or CCS? What's your favorite? I hear Andy really liked .......
332: Tube DIY Asylum, RE: What part of N.C.? (0.00)
Posted by deafbykhorns on 2017-09-09, 17:08:54 (66.177.177.194)
We frequently visit Hendersonville and Brevard .......
333: Tube DIY Asylum, RE: Steam punk meets Dr. Frankenstein.... (0.00)
Posted by deafbykhorns on 2017-09-09, 17:07:21 (66.177.177.194)
You have any older 10y, 801a or similar vintage? That would be a good project.... Irma is passing just west of us up in N Fla, we got lucky, not so much for west coast .......
334: Tube DIY Asylum, RE: I am planning to redo the grounds a little nt. (0.00)
Posted by deafbykhorns on 2017-09-06, 18:14:02 (66.177.177.194)
This is typical of how I do the ground Buss. The entire path is unbroken from front to rear, chassis ground comes off one end. 1150 supply and its dead quiet. .......
335: Tube DIY Asylum, RE: Resistance could change under load (0.00)
Posted by deafbykhorns on 2017-09-06, 13:00:56 (96.94.54.195)
.. .......
336: Tube DIY Asylum, RE: Got an annoying hi freq buzz and hum in my SE amp (0.00)
Posted by deafbykhorns on 2017-09-05, 16:42:24 (66.177.177.194)
Star ground to ground buss probably not a good idea. I don't like or trust those mechanical connections. I also try to keep ground Buss one solid piece with no splices. Other than that, your layout an .......
337: Tube DIY Asylum, RE: Independent Current Source (0.00)
Posted by deafbykhorns on 2017-09-03, 18:09:21 (66.177.177.194)
So a diode bias scheme might not be accurate when measuring impedance? Using a line output transformer pretty much solves any output impedance issues assuming it works with the tube in play....... ::: .......
338: Tube DIY Asylum, RE: Would this be the same expression? (0.00)
Posted by deafbykhorns on 2017-09-03, 08:46:47 (66.177.177.194)
-V(n003)/I(I1) The negative makes no change in plot .......
339: Tube DIY Asylum, RE: Independent Current Source (0.00)
Posted by deafbykhorns on 2017-09-03, 08:38:36 (66.177.177.194)
So are you saying this circuit could have lower impedance than the plot? .......
340: Tube DIY Asylum, RE: Got it, thanks (0.00)
Posted by deafbykhorns on 2017-09-03, 08:12:25 (66.177.177.194)
I kept wanting to input a frequency, after inserting just the voltage values, it worked fine. See below Impedance at low freq doesn't perform as well as my choke loaded 26 preamp circuit ::: TOPIC: .......
341: Tube DIY Asylum, Re: how much current? (0.00)
Posted by deafbykhorns on 2017-09-03, 07:33:33 (174.227.8.122)
how much current do you set? I assume that he use advanced settings and set for AC? .......
342: Tube DIY Asylum, LTSpice output impedance. (0.00)
Posted by deafbykhorns on 2017-09-02, 20:46:25 (66.177.177.194)
How to you show output impedance on a preamp model? I tried a current load of 1ua and added /I(I1) to the sweep.... Used AC analysis with a sweep of 1-50k .......
343: MagneQuest/Peerless Forum, B7-15k (0.00)
Posted by deafbykhorns on 2017-09-01, 17:33:23 (66.177.177.194)
Mike, Can you PM me with some spice data I can use for LTSpice. And also give me price and lead time on these trannies. Do you have gapped version of line output I could model in the 10-25ma range? :: .......
344: Tube DIY Asylum, RE: Make sure they are 1Meg as well (0.00)
Posted by deafbykhorns on 2017-09-01, 08:26:08 (96.94.54.195)
Its easy to make that mistake! .......
345: Tube DIY Asylum, RE: Found HF loss problem (0.00)
Posted by deafbykhorns on 2017-09-01, 04:36:44 (96.94.54.195)
Cascode worked to correct the HF loss but need to find device that works with the 6N6P. Couldn't get good distortion figures at 25ma, see some of the other posts. It works fine with the 26 ::: TOPIC:: .......
346: Tube DIY Asylum, RE: Works great with the 26 (0.00)
Posted by deafbykhorns on 2017-08-31, 17:19:42 (66.177.177.194)
Didn't work so well with the higher current tubes. Little gain but that might be the transformer I'm modeling. With a cap, its plenty of gain. Distortion is .03% Cap Output .......
347: Tube DIY Asylum, RE: Worked a little better but (0.00)
Posted by deafbykhorns on 2017-08-31, 16:58:45 (66.177.177.194)
distortion figures are still .3% at 10ma 25ma produces about .45% I suspect its the current, I might try a LND150 .......
348: Tube DIY Asylum, RE: WOW, good call, that worked on the high end (0.00)
Posted by deafbykhorns on 2017-08-31, 16:01:00 (66.177.177.194)
Good call, now I need some real world figures on the Line OPT. If I bypass OPT and use a cap, F3 looks good. Now the distortion is high, .48% Did I get the cascode scenario right? I suspect this is t .......
349: Tube DIY Asylum, RE: Cascode Help (0.00)
Posted by deafbykhorns on 2017-08-30, 17:42:43 (66.177.177.194)
I'm not familiar with cascode setup. What am I doing wrong here, cant get the current above 10ma. And when I do, circuit fails to operate. Works at 10ma but too much distortion at that level ::: TO .......
350: Tube DIY Asylum, RE: transformer model (0.00)
Posted by deafbykhorns on 2017-08-30, 16:47:13 (66.177.177.194)
I don't have a transformer yet, just figuring out how to model one. The LL2745/18ma can be wired for Alt Q,P or R. I'm assuming you would wire it for Alt R (staying closer to 4:1) and if it's parafeed .......
351: Tube DIY Asylum, RE: SE Line Output? (0.00)
Posted by deafbykhorns on 2017-08-30, 16:22:22 (66.177.177.194)
So it appears K&K is using the LL1671 for SE ALt Q connection with a 4:1 ratio. That being said, if the primary inductance is 35H, what would be the secondary inductance and/or formula to calculate? 2 .......
352: Tube DIY Asylum, RE: Makes sense now-revised inductance plot (0.00)
Posted by deafbykhorns on 2017-08-30, 15:39:44 (66.177.177.194)
Using your figures, I have about 10db of gain now like Twysted had in his design. And I have a peak now in LF. Is it possible to use a gapped transformer for parafeed? (In case I change my mind on ci .......
353: Tube DIY Asylum, RE: Thanks (0.00)
Posted by deafbykhorns on 2017-08-30, 06:20:37 (96.94.54.195)
That is what I was looking for! I need to write this on down for future reference. .......
354: Tube DIY Asylum, RE: transformer model (0.00)
Posted by deafbykhorns on 2017-08-30, 06:17:12 (96.94.54.195)
This is where i need help, that model is a guess. I found a Lundahl which seems to be popular for this application. For SE, primary inductance is 90h. What would the secondary inductance and series r .......
355: Tube DIY Asylum, RE: 26 w/plate choke (0.00)
Posted by deafbykhorns on 2017-08-29, 17:18:46 (66.177.177.194)
. .......
356: Tube DIY Asylum, RE: 26 w/CCS (0.00)
Posted by deafbykhorns on 2017-08-29, 17:13:17 (66.177.177.194)
5v out .04% distortion I think the CCS is setting up a filter... Choke loaded looks much better. .......
357: Tube DIY Asylum, RE: Preamp Project Part 2-6E5P Tube (0.00)
Posted by deafbykhorns on 2017-08-29, 17:00:45 (66.177.177.194)
This is using a 6E5P in triode mode Loading secondary About 5v out Distortion .00015 .......
358: Tube DIY Asylum, RE: Preamp Project Part 2-26 tube (0.00)
Posted by deafbykhorns on 2017-08-29, 16:59:03 (66.177.177.194)
This is using 26 tube 4v out- 1v in Distortion .1 This may mellow out the GM70 amp too much... Little more difficult to build, need Rod Colemans on this one .......
359: Tube DIY Asylum, Preamp Project Part 2-Circuit designs (0.00)
Posted by deafbykhorns on 2017-08-29, 16:34:28 (66.177.177.194)
Design #1- Using 6n6p as twystd suggested Lots of gain, almost 9v RMS out with 1v in Distortion .000018 I think its too much for my current amp but would come in handy with a bypass switch using a TVC .......
360: Tube DIY Asylum, RE: Things are going to pots........ (0.00)
Posted by deafbykhorns on 2017-08-29, 10:26:09 (96.94.54.195)
I guess it wouldn't (in this scenario) but traditionally I would think 100K across the grid is typical and the input would connect to wiper. .......
361: Tube DIY Asylum, RE: Things are going to pots........ (0.00)
Posted by deafbykhorns on 2017-08-29, 08:06:54 (96.94.54.195)
Shouldnt the center wiper go to the input jack so that the grid resistance is constant? .......
362: Tube DIY Asylum, RE: Things are going to pots........ (0.00)
Posted by deafbykhorns on 2017-08-28, 17:16:59 (66.177.177.194)
Wouldn't the resistance of pot serve as a grid resistor? Is the center tap being used as input? .......
363: Tube DIY Asylum, RE: Preamp build (0.00)
Posted by deafbykhorns on 2017-08-17, 07:59:51 (96.94.54.195)
Whats the secondary impedance? 600? I'll run some spice calcs when I get back from vacation .......
364: Tube DIY Asylum, RE: Preamp build (0.00)
Posted by deafbykhorns on 2017-08-16, 18:29:28 (66.177.177.194)
Similar to this design? I have been considering an "iron heavy" design to match my boat anchor... .......
365: Tube DIY Asylum, RE: Preamp build (0.00)
Posted by deafbykhorns on 2017-08-16, 12:08:41 (96.94.54.195)
Most my sources are OK, vinyl source is slightly on the low side but I can live with that since I don't usually crank it up with that source. I've been following the progress on your design as well. V .......
366: Tube DIY Asylum, RE: Preamp build-mercury relays (0.00)
Posted by deafbykhorns on 2017-08-16, 05:24:36 (96.94.54.195)
Something like this relay? Would you use single pole to keep the channels separated? or will the 2 pole provide enough isolation? Not sure about the Mosfet but I do have a CCS in my amp.... Just for f .......
367: Tube DIY Asylum, Preamp build (0.00)
Posted by deafbykhorns on 2017-08-15, 17:39:05 (66.177.177.194)
Well, summer is ending, fishing is about over so it's time to start designing a preamp to match my GM70. My GM70 goes full power with about 1.7v in. The preamp will drive the grid of a 6E5P on the GM7 .......
368: Tube DIY Asylum, RE: Good luck (0.00)
Posted by deafbykhorns on 2017-07-09, 06:00:31 (66.177.177.194)
I don't think there's a right answer. The one answer would be that everyone's sense of hearing is different. I think some can process these slight differences and some can't. Your approach is scientif .......
369: Tube DIY Asylum, RE: Has anyone else tried this experiment? (0.00)
Posted by deafbykhorns on 2017-07-08, 03:49:46 (66.177.177.194)
I have only done this with speaker cables swap. Did you try this with higher sound levels using dynamic music content? .......
370: Tube DIY Asylum, RE: Has anyone else tried this experiment? (0.00)
Posted by deafbykhorns on 2017-07-08, 03:34:10 (66.177.177.194)
I can hear differences when I switch out OPT transformers and that's without a switch. Are you using the same manufacture and similar specs on OPT's? I always felt like the OPT was 75% of the sound qu .......
371: Tube DIY Asylum, RE: Depends on how it's biased (0.00)
Posted by deafbykhorns on 2017-06-19, 18:09:35 (66.177.177.194)
If standard cathode bias, an open cathode shouldn't red plate the tube? .......
372: Tube DIY Asylum, RE: non-inverting preamp w/schematic ver. 2 (0.00)
Posted by deafbykhorns on 2017-06-18, 15:26:43 (107.181.69.218)
Does LT Spice calculate impedance for you? If so, whats the method? .......
373: Tube DIY Asylum, RE: Depends on what kind of meter you have (0.00)
Posted by deafbykhorns on 2017-06-18, 14:47:25 (107.181.69.218)
Any good Simpson can be wired just like you say. I like to include a fuse for insurance. .......
374: Tube DIY Asylum, RE: I liked the BADBOY tubes in his store (0.00)
Posted by deafbykhorns on 2017-06-12, 16:51:06 (66.177.177.194)
.. .......
375: Tube DIY Asylum, RE: Misunderstood (0.00)
Posted by deafbykhorns on 2017-06-10, 16:13:20 (66.177.177.194)
Vinnie, I don't think TK was being condescending, sometimes it's difficult to interpret the tone of an email or post. This new digital world can be challenging at times.... Engineers deal with facts, .......
376: Tube DIY Asylum, RE: final update .... (0.00)
Posted by deafbykhorns on 2017-06-10, 04:01:28 (66.177.177.194)
Are you testing the amplifiers at all listening levels? I find that many amps do sound similar or the same at low levels but when pushed the shortcomings are apparent. I start my testing with somethin .......
377: Tube DIY Asylum, RE: triode vs pentode connection (0.00)
Posted by deafbykhorns on 2017-06-04, 14:43:58 (66.177.177.194)
Simply tie the screen to the plate with a resistor like the first stage for triode connection. The screen is tied to B+ per your schematic right now .......
378: Tube DIY Asylum, RE: Finally ........... it's done. (0.00)
Posted by deafbykhorns on 2017-05-31, 04:45:32 (96.94.54.195)
Looks nice, what was the final power output in this configuration? Let's see your final schematic if you dont mind sharing .......
379: Tube DIY Asylum, RE: What he said... (0.00)
Posted by deafbykhorns on 2017-05-13, 05:43:59 (66.177.177.194)
"Who builds a tube amp with no chassis ventilation? No wonder it gets hot." One of those uneducated voters? .......
380: Tubes Asylum, Heathkit Cap tester (0.00)
Posted by deafbykhorns on 2017-05-06, 15:28:07 (45.56.148.201)
Anyone notice that the Heathkit IT11,28 have almost tripled in price since a video was posted a few weeks ago? Any modern day versions of this type of tester? Besides an ESR .......
381: Tube DIY Asylum, RE: What is the function generator used for this test? (0.00)
Posted by deafbykhorns on 2017-05-02, 15:07:10 (66.177.177.194)
10khz performance isn't that bad on the Hammond as well and this is were the monolith shines. I performed the same sweep on Hammond and it was 8-100khz though the power saturation spec might be differ .......
382: Tube DIY Asylum, RE: GM70 OPT update (0.00)
Posted by deafbykhorns on 2017-05-02, 13:03:06 (66.177.177.194)
Hipot test is 2kv Add gain on top of that and yikes! The hammonds were a good starting point, i didn't want to invest more until I was sure with my design. This was my first 1kv+ amplifier ::: TOPIC:: .......
383: Tube DIY Asylum, RE: apples to engines comparison... (0.00)
Posted by deafbykhorns on 2017-05-02, 09:48:12 (66.177.177.194)
My review was based with both scenarios hooked up using IT I made the IT change and then the new opt months later Here's a snapshot of the Hammond after the IT change. Still not too bad and mad a diff .......
384: Tube DIY Asylum, RE: GM70 OPT update (0.00)
Posted by deafbykhorns on 2017-05-02, 09:45:16 (174.227.4.74)
Yes they are a bit more. For the money, the Hammond is a good purchase. With horns, there's a little more synergy with the new transformers .......
385: Tube DIY Asylum, RE: Screen voltage regulator. (0.00)
Posted by deafbykhorns on 2017-05-01, 18:46:02 (66.177.177.194)
This is a nice regulator! I have used these in the past, well worth the cost! .......
386: SET Asylum, RE: Yeah, right. All of it? (0.00)
Posted by deafbykhorns on 2017-05-01, 18:40:50 (66.177.177.194)
And here we go with the race card again.... Reason why I stay off twitter, Facebook and all the other social media pages....please don't turn this forum into one of those. My old man always said you g .......
387: Tube DIY Asylum, RE: GM70 OPT update (0.00)
Posted by deafbykhorns on 2017-05-01, 17:53:36 (66.177.177.194)
Yes, it was pretty dramatic. No global feedback, SE GM70, 1150v is a little dangerous to starting clipping in caps. Not so sure this little bit of ringing is important on a sq wave. My Slagle transfor .......
388: Tube DIY Asylum, GM70 OPT update (0.00)
Posted by deafbykhorns on 2017-05-01, 17:08:23 (66.177.177.194)
Just mounted the Monolithmagnetics 8k transformer which replaced a Hammond 6.5K. I chose the S-5 gapped at 90ma, fsat=21 Hz @ 25 Wrms L=57H. Also changed from plate choke to IT driver using modified m .......
389: Tube DIY Asylum, RE: A contractors perspective (0.00)
Posted by deafbykhorns on 2017-04-17, 07:38:39 (96.94.54.195)
. .......
390: Tube DIY Asylum, RE: Hammond hum (0.00)
Posted by deafbykhorns on 2017-03-28, 18:33:22 (66.177.177.194)
These hum like hell if run within 75% of rating based on my experience. I would also verify with PSUD program .......
391: Tube DIY Asylum, RE: In what spirit do you ask the question ??.. (0.00)
Posted by deafbykhorns on 2017-03-02, 07:16:44 (96.94.54.195)
I run mine at 45-46ma so I should be good! .......
392: Tube DIY Asylum, RE: In what spirit do you ask the question ??.. (0.00)
Posted by deafbykhorns on 2017-03-01, 12:29:45 (96.94.54.195)
Just curious, how many JJ2A3's do you own? I have 6 right now and expect these to last at least 10 years since I'm biasing low. .......
393: Tubes Asylum, RE: wouldn't work for me..... (0.00)
Posted by deafbykhorns on 2017-02-16, 16:36:14 (66.177.177.194)
Now I know why there's no tubes to be had! Same goes with vintage gear.... .......
394: Tube DIY Asylum, RE: Or Rod Coleman supplies (0.00)
Posted by deafbykhorns on 2017-02-09, 18:37:33 (66.177.177.194)
. .......
395: Tube DIY Asylum, RE: Arrrrrgh! (0.00)
Posted by deafbykhorns on 2017-02-08, 12:19:21 (96.94.54.195)
This power supply wont work at low voltage. Takes about 70-80v for it to start working, by that time you will have blown your 26 tubes .......
396: Tube DIY Asylum, RE: Electronic Transformer heating for the gm70 test (0.00)
Posted by deafbykhorns on 2017-01-29, 10:09:45 (66.177.177.194)
First, you need to reduce oscillating windings and you will get 65khz Second, you need to still add a hum pot to null the HV Third, add 3-4 windings to get your 20v .......
397: Tube DIY Asylum, RE: microcontroller help (0.00)
Posted by deafbykhorns on 2017-01-26, 16:49:48 (66.177.177.194)
If you need resolution either way, try 3volts. 5 volts is the max you should run the input pin. Resolution works very well for me .......
398: Tube DIY Asylum, RE: Did mine a little different (0.00)
Posted by deafbykhorns on 2017-01-26, 16:46:49 (66.177.177.194)
Just another divider network. More resistance, much smaller wattage resistors required and a way to calibrate your arduino input. The zener is not required but will protect the arduino if voltage goes .......
399: Tube DIY Asylum, RE: Did mine a little different (0.00)
Posted by deafbykhorns on 2017-01-25, 16:40:52 (66.177.177.194)
This one doesn't pull as much current and zener protects over voltage. I can calibrate with pot as well, this should give a little more isolation. I would download LTSpice, you can model these divider .......
400: Tube DIY Asylum, RE: what kind of builder (0.00)
Posted by deafbykhorns on 2017-01-21, 04:09:45 (66.177.177.194)
You will need the 220v at 120 input supply to get that low .......
401: Tube DIY Asylum, RE: what kind of builder (0.00)
Posted by deafbykhorns on 2017-01-20, 17:00:22 (66.177.177.194)
Add 5 turns to the output toroidal and you get 20volts These have been tested and work well I have tried both the Coleman and the Ultrasonic, i could flip a coin on either one but the halo is much eas .......
402: Tube DIY Asylum, RE: GM70 OPT selection (0.00)
Posted by deafbykhorns on 2017-01-17, 18:33:54 (66.177.177.194)
I was thinking the same, if they can gap to 90ma, that would put fsat closer to 21hz and probably about 55H .......
403: Tube DIY Asylum, GM70 OPT selection (0.00)
Posted by deafbykhorns on 2017-01-16, 17:47:23 (96.94.54.195)
Looking at upgrading the iron on my GM70 amps Currently using some Hammond 6500ohm 100ma 30w 55H Running tubes at 1050-1100v, 90ma I really liked what the Monolith Magnetics IT did for these amps so l .......
404: Tube DIY Asylum, RE: Output Transformer (0.00)
Posted by deafbykhorns on 2017-01-12, 04:29:33 (96.94.54.195)
I just used another tube behind the first TX to get it oscillating. Not practical but got the job done. .......
405: Tube DIY Asylum, RE: Output Transformer (0.00)
Posted by deafbykhorns on 2017-01-09, 17:44:43 (66.177.177.194)
The second transformer works fine, I tried it with the halo supplies and it works fine. I got about 1.6v with the second toroidal playing around with the windings. Your circuit seems to work with a 24 .......
406: Tube DIY Asylum, RE: A New Ultrasonic Heater (0.00)
Posted by deafbykhorns on 2017-01-07, 16:22:51 (66.177.177.194)
Thanks, I'll order some parts in the next week and start some bread boarding. That MOSFET you chose looks robust enough to power our transmitting tubes. The step down may be the tricky part, probably .......
407: Tube DIY Asylum, RE: GFIs are set to trip below 5ma (0.00)
Posted by deafbykhorns on 2017-01-07, 15:31:43 (66.177.177.194)
If your doing some live testing, do it with a GFI circuit so you don't feel the effects for more than 40 milliseconds.... Never been shocked by more than 60cycles, I might have to ask a couple of my N .......
408: Tube DIY Asylum, RE: Maybe if we were retired (0.00)
Posted by deafbykhorns on 2017-01-07, 15:26:59 (66.177.177.194)
I'm sure Jack's daytime job pays more....I know mine does. Besides, its just a hobby and fun for the rest of us. .......
409: Tube DIY Asylum, RE: A New Ultrasonic Heater (0.00)
Posted by deafbykhorns on 2017-01-06, 21:07:03 (66.177.177.194)
If there's some interest, I might take on the circuit board design. Im not a EE by law but have made some gerber files in the past, there's a couple sites that also have some online software to produc .......
410: Tube DIY Asylum, RE: help deciphering label ...... (0.00)
Posted by deafbykhorns on 2017-01-03, 15:40:38 (45.56.148.43)
Use the 115v connections, your probably at 118-124 at your house. .......
411: Tube DIY Asylum, RE: try the 220v input supplies (0.00)
Posted by deafbykhorns on 2017-01-03, 15:34:00 (45.56.148.43)
They have more primary windings and will run off 120volt, you can remove enough secondary windings to get around 3 volts or less. I may try to add some primary windings which should lower the voltage .......
412: Tube DIY Asylum, RE: You dirty dog!!! (0.00)
Posted by deafbykhorns on 2017-01-03, 12:52:39 (96.94.54.195)
You had me on a treasure hunt ;-) .......
413: Tube DIY Asylum, RE: And an E8 base but a nice looking triode (0.00)
Posted by deafbykhorns on 2017-01-03, 10:53:37 (96.94.54.195)
. .......
414: Tube DIY Asylum, RE: 6SL7 with a MOSFET source follower (0.00)
Posted by deafbykhorns on 2017-01-03, 10:38:26 (96.94.54.195)
Yeah, not something I would be interested in doing. Dave Slagle had a nice looking tube to try. .......
415: Tube DIY Asylum, RE: Octals-med mu, low plate R (0.00)
Posted by deafbykhorns on 2017-01-03, 10:37:06 (96.94.54.195)
Looks like my 6E5P without the G2! Not an octal but I'll try it out Edit: Do you buy up all the 8213's Dave? Not an easy tube to find... .......
416: Tube DIY Asylum, RE: I hear ya (0.00)
Posted by deafbykhorns on 2017-01-03, 10:19:55 (96.94.54.195)
I wanted to avoid that and just wondering if there's any octals that do similar jobs. Maybe not due to the size and structure of tube. For now, I'm sticking with the 6E5P. It runs circles around the m .......
417: Tube DIY Asylum, Octals-med mu, low plate R (0.00)
Posted by deafbykhorns on 2017-01-02, 18:13:30 (66.177.177.194)
Well, I moved from the 76 driver looking for a med mu driver for the 300b-GM70 5687 didn't have enough gain, sounded ok but nothing like the 76 7788 oscillates like crazy (probably long alligator clip .......
418: Tube DIY Asylum, RE: SE OT swap (0.00)
Posted by deafbykhorns on 2016-12-29, 12:53:39 (96.94.54.195)
You might get a slight gain along with slightly higher distortion levels (nothing audible). .......
419: Tube DIY Asylum, RE: +1 Dave, this is why (0.00)
Posted by deafbykhorns on 2016-12-29, 10:44:21 (96.94.54.195)
so many combinations for cartridges and preamps don't have the "synergy" as some would put it..... Next time I need a step up MC, I'm going to Dave for help! .......
420: Tube DIY Asylum, RE: Lighting Transformers -Old and New (0.00)
Posted by deafbykhorns on 2016-12-28, 15:08:46 (66.177.177.194)
Anything is possible with the right toroidal .......
421: Tube DIY Asylum, RE: +1 on gridstopper (0.00)
Posted by deafbykhorns on 2016-12-27, 18:17:03 (66.177.177.194)
. .......
422: Tube DIY Asylum, RE: Lighting Transformers -Old and New (0.00)
Posted by deafbykhorns on 2016-12-27, 17:48:50 (66.177.177.194)
The yam should already be set around 65khz. Based on my experiments, I think you'll need to add primary windings to get 2.5volts .......
423: Tube DIY Asylum, RE: Yes, swapped tubes and it worked! (0.00)
Posted by deafbykhorns on 2016-12-27, 08:31:24 (96.94.54.195)
Connected G2 to Anode via stopper for triode mode. G3 appears to be connected to shield according to data sheet Connected G3 to cathode, no stopper, Oscillates Connect G3 to ground, does not oscillate .......
424: Tube DIY Asylum, RE: Yes, swapped tubes and it worked! (0.00)
Posted by deafbykhorns on 2016-12-26, 18:18:59 (66.177.177.194)
Good call! G3 to ground works good now but the gain sucks in this configuration. Tied G3 back to cathode, works now but getting about a 5k oscillation, might be the long alligator clip leads. Might tr .......
425: Tube DIY Asylum, RE: Magnequest BCP16ni (0.00)
Posted by deafbykhorns on 2016-12-26, 18:12:48 (66.177.177.194)
Never thought about putting one at the input tube. I have a couple magnequest bcp16 nickel chokes lying around I might try. .......
426: Tube DIY Asylum, RE: 6E5P (0.00)
Posted by deafbykhorns on 2016-12-26, 16:17:42 (66.177.177.194)
Maxamillion, what does the choke to ground do in lieu of a resistor in your amp? I don't need grid current so I chose the CCS, I will say this has been one of my favorite tubes so far for my amp. It d .......
427: Tube DIY Asylum, RE: CCS Issue (0.00)
Posted by deafbykhorns on 2016-12-26, 16:09:29 (66.177.177.194)
The 6E5P is a Russian tube capable of 8.3watts dissipation Ik max is 100ma Absolutely no oscillation I can see on a scope. Maximillion (Magz) used this tube to drive a 833, it's a nice tube and behave .......
428: Tube DIY Asylum, RE: IXCP10M90S (0.00)
Posted by deafbykhorns on 2016-12-26, 13:53:33 (66.177.177.194)
I did replace the 10M90s. Somehow the input voltage is setting up the current and it wont revert back. This is the same regulator as the 10M45s only a higher voltage rating. It's dissipating about 6.5 .......
429: Tube DIY Asylum, RE: G3 to cathode oscillates (0.00)
Posted by deafbykhorns on 2016-12-26, 12:58:04 (66.177.177.194)
The 7788 tube did not perform well with G3 tied to cathode, distortion and hum which sounded like some HF oscillation. With G3 tied to ground, oscillation went away but tube did not perform, plate vol .......
430: Tube DIY Asylum, RE: IXCP10M90S (0.00)
Posted by deafbykhorns on 2016-12-26, 12:17:29 (66.177.177.194)
. .......
431: Tube DIY Asylum, CCS Issue (0.00)
Posted by deafbykhorns on 2016-12-26, 09:20:25 (66.177.177.194)
I modeled this CCS in LTSpice and voltage and current are right on the money when I fired this thing up. Seems to perform well and doing its job. However, I stumbled on an issue when I fired up the am .......
432: Tube DIY Asylum, RE: question regarding halo transformers..... (0.00)
Posted by deafbykhorns on 2016-12-26, 05:36:38 (66.177.177.194)
I cut off the extra unless you want to leave it for future tubes (might need more wraps) .......
433: Tube DIY Asylum, RE: Article far from KISS (0.00)
Posted by deafbykhorns on 2016-12-25, 07:10:29 (66.177.177.194)
I think this guy likes to hear himself talk. Too much rambling Should of applied KISS to his writings...... .......
434: Tube DIY Asylum, RE: Check the phase splitter (0.00)
Posted by deafbykhorns on 2016-12-25, 06:10:20 (66.177.177.194)
I found unmatched tubes can make it sound grainy .......
435: Tube DIY Asylum, RE: What mail? (0.00)
Posted by deafbykhorns on 2016-12-24, 19:15:51 (66.177.177.194)
Don't see any mail.... .......
436: Tube DIY Asylum, RE: i phoned a friend (0.00)
Posted by deafbykhorns on 2016-12-24, 12:41:02 (66.177.177.194)
And he said to tie G3 to cathode and G2 to the plate (anode) 2 vs 1 answers so far.... .......
437: Tube DIY Asylum, RE: What are you using to drive the output transfomer? (0.00)
Posted by deafbykhorns on 2016-12-24, 12:34:37 (66.177.177.194)
The 833? That might happen once I retire.... .......
438: Tube DIY Asylum, RE: What are you using to drive the output transfomer? (0.00)
Posted by deafbykhorns on 2016-12-24, 08:50:47 (66.177.177.194)
Jeff, not my Khorn system, this is for my office system which drives 88db speakers I had a nice Audio Research D115 but the GM70 is a little nicer, just need a little more gain on the front end. ::: T .......
439: Tube DIY Asylum, RE: Pentode or tetrode in triode mode (0.00)
Posted by deafbykhorns on 2016-12-24, 08:47:10 (66.177.177.194)
"I have the same question about G3" About using a grid stop or where to tie? .......
440: Tube DIY Asylum, RE: Been there,, done that (0.00)
Posted by deafbykhorns on 2016-12-24, 08:44:46 (66.177.177.194)
Just experimenting and learning how to use other tubes. I have not grasped the use of pentodes and tetrodes. Trying to drive a JJ2A3 with a little more gain other than using your standard 12ax7 variet .......
441: Tube DIY Asylum, Pentode or tetrode in triode mode (0.00)
Posted by deafbykhorns on 2016-12-24, 04:55:04 (66.177.177.194)
Do I tie G3 to anode? And where does the screen G2 tie?cathode?with or without a resistor? .......
442: Tube DIY Asylum, RE: What are you using to drive the output transfomer? (0.00)
Posted by deafbykhorns on 2016-12-24, 04:52:47 (66.177.177.194)
GM70 is driving the OPT IT is after the JJ2A3 .......
443: Tube DIY Asylum, Hammond GM70 opt (0.00)
Posted by deafbykhorns on 2016-12-23, 20:10:34 (66.177.177.194)
Seems I need some new OPT iron unless I'm missing something? Purple trace is output of IT Yellow is Hammond OPT with 8ohm resistor Shots taken at 1k,5k and 10khz Replaced IT with monolith magnetics, s .......
444: Tube DIY Asylum, RE: 240 volt modules (0.00)
Posted by deafbykhorns on 2016-12-22, 18:47:20 (66.177.177.194)
I was able to get mine down below that voltage. In fact, I got the 120v version to 5v so the 220v version should almost drive a 2A3 .......
445: Tube DIY Asylum, RE: Have you tried the Colemans yet? (0.00)
Posted by deafbykhorns on 2016-12-15, 06:21:06 (96.94.54.198)
. .......
446: Tube DIY Asylum, RE: lighting transformer 2a3 (0.00)
Posted by deafbykhorns on 2016-12-13, 18:44:55 (66.177.177.194)
You can remove about 40% of secondary windings before the transformer quits working. As triode_k said, adding primary windings is the best way It's about a 12:1 (or more) winding ratio depending on wh .......
447: Tube DIY Asylum, RE: Converting 2 stages 845 amplifier with GM70? (0.00)
Posted by deafbykhorns on 2016-12-11, 14:58:39 (174.227.142.212)
That's a lot of voltage for an IT One company that comes to mind is Monolith magnetics .......
448: Tube DIY Asylum, RE: Converting 2 stages 845 amplifier with GM70? (0.00)
Posted by deafbykhorns on 2016-12-11, 11:41:12 (174.227.9.251)
The mu is only a couple points different Maybe 2-3db more sensitive I would say build it as shown. Did you find any spice models on that driver? It has a mu of 300? .......
449: SET Asylum, RE: Is that why SS sounds like crap? (0.00)
Posted by deafbykhorns on 2016-12-10, 15:20:35 (66.177.177.194)
Solid state does the same thing, they basically parallel transistors in most amp circuits. Some manufacturers match transistors which brings us back to the subject of smearing. I think if you match th .......
450: Tube DIY Asylum, RE: Use DALE RH-25 or RH50 and heat sink them (0.00)
Posted by deafbykhorns on 2016-12-10, 15:12:47 (66.177.177.194)
Keep in mind, these may not protect your OPT from catastrophic failure. You would want to monitor the current, fuse or have the cathode resistor fail open if the tube shorts. I use an arduino to monit .......
451: Tube DIY Asylum, RE: Using a 220v input Electronic Transformer-No mods to oscillator (0.00)
Posted by deafbykhorns on 2016-12-10, 15:01:34 (66.177.177.194)
Here's one from a company called YAM No mods needed on oscillator as this one is set from factory with 2 turns for a net of 62KHZ. 220v Input with 120v line voltage nets about 7.8 volts. Pull off a co .......
452: Tube DIY Asylum, RE: Lighting Transformer for transmitting tubes GM70 (0.00)
Posted by deafbykhorns on 2016-12-10, 10:37:32 (66.177.177.194)
Yes, scope shot is under load. That makes more sense on the toroid tx, I wasn't sure if it was the wire wrapped around primary or core. Either way, that sq wave wave looks pretty darn good! I'm doing .......
453: Tube DIY Asylum, Lighting Transformer for transmitting tubes GM70 (0.00)
Posted by deafbykhorns on 2016-12-10, 06:25:49 (66.177.177.194)
Here's a 160watt electronic transformer modified for the GM 70 Added 3 windings to toroid to net about 20volts Removed all but 1-1/2 windings from oscillator Added 220uf cap to rectifier Ultrasonic fr .......
454: Tube DIY Asylum, RE: Dowdy Llama inspired? (0.00)
Posted by deafbykhorns on 2016-12-09, 21:17:29 (66.177.177.194)
Except for the driver and operating voltage, it sounds like a dowdy amp .......
455: SET Asylum, RE: as well as entertaining (0.00)
Posted by deafbykhorns on 2016-12-09, 19:18:20 (66.177.177.194)
,! .......
456: Tube DIY Asylum, RE: Parafeed GM70 Prototype Build (0.00)
Posted by deafbykhorns on 2016-12-09, 19:01:13 (66.177.177.194)
I thought it was a pentode with that mu! Great operating point for the gm70, I had mine at 1200v but lowered just under 1100v. How did you configure the power supply, who's toroidal? I used spice to m .......
457: Tube DIY Asylum, RE: Parafeed GM70 Prototype Build (0.00)
Posted by deafbykhorns on 2016-12-09, 18:17:37 (66.177.177.194)
What kind of voltage and current are you running on the outputs? Cathode bias? Are you using the same high voltage for the pentode? Is the pentode in triode mode or pentode? Don't you have to run thes .......
458: Tube DIY Asylum, RE: Does the H in Hammond stand for hum? (0.00)
Posted by deafbykhorns on 2016-12-09, 18:13:12 (66.177.177.194)
I forgot about Fair Radio! Did you have cap or choke input? I assume these where powering your 211's I might not need the cap input with 1900volts. With 120-123v input on a 1900v output should net me .......
459: Tube DIY Asylum, RE: Does the H in Hammond stand for hum? (0.00)
Posted by deafbykhorns on 2016-12-09, 18:05:38 (66.177.177.194)
That will lower the voltage about 15%-20% which might not be a bad thing. Chokes are rock solid and way oversized, dead quiet with cap. .......
460: Tube DIY Asylum, Does the H in Hammond stand for hum? (0.00)
Posted by deafbykhorns on 2016-12-09, 14:33:25 (66.177.177.194)
GM70 supply 90ma 726 series Hammond 300ma 6ax4 rectifier CLCLC First cap is .7uf Mechanical hum Hammond replaced one that was really bad but they still hum Any suggestions for a better built potted? O .......
461: Tube DIY Asylum, RE: an interesting journey (0.00)
Posted by deafbykhorns on 2016-12-09, 05:12:12 (96.94.54.198)
Start another thread for your build. I have a GM70 build right now and can share my experiences. .......
462: Tube DIY Asylum, RE: an interesting journey (0.00)
Posted by deafbykhorns on 2016-12-08, 16:25:45 (66.177.177.194)
Only thing your missing now is a Rod Coleman supply. These are pretty sweet for the 26 tubes. .......
463: Tube DIY Asylum, RE: final update for my halo trans sojurn..... (0.00)
Posted by deafbykhorns on 2016-12-08, 09:53:30 (96.94.54.198)
Are you still using the hum pot method with the bias? Dave Slagle brought up a good point if your grounding one side .......
464: Tube DIY Asylum, RE: 240 voltage modules better for lower voltage tubes (0.00)
Posted by deafbykhorns on 2016-12-08, 09:51:26 (96.94.54.198)
The best I could reduce the voltage before the transformer quits working is about 8-9 turns off or about 5volts. I ordered some 220v supplies and will post results once I start testing. My thought was .......
465: Tube DIY Asylum, RE: Why is Square / Rectangular Wave Deal of the Day? (0.00)
Posted by deafbykhorns on 2016-12-08, 06:24:33 (96.94.54.198)
In Dave's cathode supply where one leg is tied to ground without a humpot, I can see where that may be an issue. I might experiment with this on a GM70 once I get the 120w units. Attached a picture of .......
466: Tube DIY Asylum, RE: Picture of latest Ebay board (0.00)
Posted by deafbykhorns on 2016-12-07, 17:51:42 (107.181.69.204)
Same method as above just the newer boards you can find on Ebay. Just search for "Electronic transformer" and find one that looks like the attached picture. You can find them up to about 130watt and .......
467: Tube DIY Asylum, RE: Modifying the Lighting Transformer (0.00)
Posted by deafbykhorns on 2016-12-07, 17:43:15 (107.181.69.204)
Triode, what if he reversed the winding direction? Does it matter? .......
468: Tube DIY Asylum, RE: Photo and notes of modifications (0.00)
Posted by deafbykhorns on 2016-12-07, 17:39:34 (107.181.69.204)
. .......
469: Tube DIY Asylum, RE: My shots at different scales w & w/o capacitor (0.00)
Posted by deafbykhorns on 2016-12-07, 15:59:04 (66.177.177.194)
Now this gets interesting, this is on my variac with 60vac in. Output freq goes up and voltage is about half. I wonder if a 220-230v electronic transformer would do the same with 120vac input. Might w .......
470: Tube DIY Asylum, RE: take a look at the my photo in "another update" (0.00)
Posted by deafbykhorns on 2016-12-07, 15:44:54 (107.181.69.204)
The center winding does not have any wraps. The outside windings are just one wrap, not sure if direction makes a difference but I would think so, keep each winding identical just in case... ::: TOPIC .......
471: Tube DIY Asylum, RE: My shots at different scales w & w/o capacitor (0.00)
Posted by deafbykhorns on 2016-12-07, 15:32:40 (66.177.177.194)
The Fluke seems to somewhat agree with the scope. Without the cap is 12v, with the cap is 14.7 I believe removing about 3 windings from the toroidal will net about 10.5 if I recall. .......
472: Tube DIY Asylum, RE: another update.... (0.00)
Posted by deafbykhorns on 2016-12-06, 18:07:10 (66.177.177.194)
We appear to both have the same supplies/boards If you haven't removed any windings, you should net about 13v with a 220uf cap. I did this with a 1.3amp load, here's a scope shot of what mine looked l .......
473: Tube DIY Asylum, RE: yes, that's the one (0.00)
Posted by deafbykhorns on 2016-12-06, 17:47:37 (66.177.177.194)
Just unsolder, rewind and resolder .......
474: Tube DIY Asylum, RE: a breakthrough at last...... (0.00)
Posted by deafbykhorns on 2016-12-06, 08:44:18 (66.177.177.194)
32.5khz is correct prior to removing some coils off the oscillator transformer. I have this same exact supply, removing a couple coils should net you around 65KHZ. That needs to be your next step and .......
475: Tube DIY Asylum, RE: it does get flaky, try playing with range (0.00)
Posted by deafbykhorns on 2016-12-05, 10:28:22 (96.94.54.195)
I found on my Fluke 87 that if I use a certain range, its pretty close. Automatic range will bounce back all sorts of voltages depending on which range scale the reading falls on. I can back check thi .......
476: Tube DIY Asylum, RE: The lower wattage have toroidal (0.00)
Posted by deafbykhorns on 2016-12-04, 18:35:14 (66.177.177.194)
I have the 60 and 80w units .......
477: Tube DIY Asylum, RE: pull some windings off the smaller choke and (0.00)
Posted by deafbykhorns on 2016-12-04, 10:36:15 (66.177.177.194)
You should raise the output freq .......
478: Tube DIY Asylum, RE: Making it Work (0.00)
Posted by deafbykhorns on 2016-12-04, 06:32:34 (66.177.177.194)
Why not just unwrap one of the windings on toroidal, one or two shouldn't hurt anything. I was able to drop it down to 4.5 volts before the transformer gave out(saturated?) .......
479: Tube DIY Asylum, RE: ok, what is happening here???? (0.00)
Posted by deafbykhorns on 2016-12-03, 20:10:08 (66.177.177.194)
Mine looks a lot better than that one. I removed a couple turns and got it down to 10volts I use some old used up 6550's in series to load the supply before using the real tube .......
480: Tube DIY Asylum, RE: Cathode caps? (0.00)
Posted by deafbykhorns on 2016-12-02, 18:44:00 (66.177.177.194)
. .......
481: Tube DIY Asylum, RE: what are those large weird looking caps? (0.00)
Posted by deafbykhorns on 2016-12-02, 17:31:34 (66.177.177.194)
. .......
482: Tube DIY Asylum, RE: Well all the parts finally got here...... (0.00)
Posted by deafbykhorns on 2016-12-02, 16:46:29 (66.177.177.194)
I've done a few of these halogen supply's in the past. Just don't forget to add the capacitor to the supply Anxious to see how you like it! .......
483: Tube DIY Asylum, RE: Your nails need trimming... (0.00)
Posted by deafbykhorns on 2016-11-27, 16:39:55 (66.177.177.194)
. .......
484: Tube DIY Asylum, RE: Not enough gain on 76 (0.00)
Posted by deafbykhorns on 2016-11-27, 16:36:47 (66.177.177.194)
Yeah, probably why I never liked my 300b amp with two stages. 76-26-300B was magic .......
485: Tube DIY Asylum, RE: This looks good on paper (0.00)
Posted by deafbykhorns on 2016-11-27, 15:12:15 (66.177.177.194)
A little tweaking and this might work well. About 1 volt input for full A1 power output Or should I use the other half of 5687 for CCS? .......
486: Tube DIY Asylum, Not enough gain on 76 (0.00)
Posted by deafbykhorns on 2016-11-26, 18:32:19 (66.177.177.194)
Feeding a 300b (JJ2A3) to drive a GM70 (via Monolith Magnetics IT) Though the 76 has that magical sound, it needs a preamp to drive to full power. Gain is about 10x on the 76, need more like 20x. Any .......
487: Tube DIY Asylum, RE: Thanks! And Happy Thanksgiving to all (0.00)
Posted by deafbykhorns on 2016-11-23, 18:19:59 (66.177.177.194)
Our friends on Tube DIY! .......
488: Tube DIY Asylum, RE: Equals maybe? (0.00)
Posted by deafbykhorns on 2016-11-23, 05:55:08 (96.94.54.198)
Fairchild has SSP1N60, SSP2N60? or a IXCP10M90S Infineon SPA02N80C3 has models, not sure if its a close equal. Higher voltage/current .......
489: Tube DIY Asylum, AOT1N60 mosfet spice (0.00)
Posted by deafbykhorns on 2016-11-22, 17:59:11 (66.177.177.194)
Looking for some spice files for this mosfet as well as some other popular HV mosfets. Trying to model some power drive circuits .......
490: Tube DIY Asylum, RE: i like the ultrasonic better (0.00)
Posted by deafbykhorns on 2016-11-19, 11:37:06 (66.177.177.194)
than the colemans. Much easier to implement too. For the output tube... I use the colemans for my 26 tubes .......
491: Tube DIY Asylum, RE: that appears to be a LED dimmer (0.00)
Posted by deafbykhorns on 2016-11-19, 11:36:12 (66.177.177.194)
Ive used these in the field for lighting. I believe these are pulse width modulated for LEDs .......
492: Tube DIY Asylum, RE: remove some turns from the toroidal (0.00)
Posted by deafbykhorns on 2016-11-19, 11:32:52 (66.177.177.194)
next to those transistors I think I ended up with 3 turns to get 65khz .......
493: Tube DIY Asylum, RE: I use the Colemans on the DHT preamp stages (0.00)
Posted by deafbykhorns on 2016-11-19, 11:28:25 (66.177.177.194)
They are a good compromise between AC and standard DC supplies .......
494: Tube DIY Asylum, RE: Gives you the best of both worlds (0.00)
Posted by deafbykhorns on 2016-11-18, 16:53:25 (66.177.177.194)
He mentioned he uses them for his 211 tubes in a post a couple weeks ago. RayP is doing the same thing with good results, see his post above. I think some are hesitant to try since it takes some tinke .......
495: Tube DIY Asylum, RE: You have a Fluke 87? (0.00)
Posted by deafbykhorns on 2016-11-18, 15:33:37 (66.177.177.194)
check the frequency of the AC voltage or use your scope. Since its a switching supply, its probably a a frequency above hearing levels. Like the ultrasonic supply in another post They are usually 50kh .......
496: Tube DIY Asylum, RE: Gives you the best of both worlds (0.00)
Posted by deafbykhorns on 2016-11-18, 15:24:45 (66.177.177.194)
Ultrasonic above hearing levels AC heated!!! All you do is add a capacitor at the rectifier to smooth the waveform. Depending on the frequency, you can make it higher by removing a couple windings. Fr .......
497: Tube DIY Asylum, RE: This would work well (0.00)
Posted by deafbykhorns on 2016-11-18, 12:32:50 (96.94.54.198)
from 50-160 watt Do the math, I would use 200% duty or twice the current rating. I would think the 120w would be more than enough .......
498: Tube DIY Asylum, RE: Do both (0.00)
Posted by deafbykhorns on 2016-11-09, 16:41:36 (66.177.177.194)
I used the 26 and 76 in front of my 2A3 Best of both worlds Here's a quickie I did using cathode follower .......
499: Tube DIY Asylum, RE: Take a look at some DHT tubes (0.00)
Posted by deafbykhorns on 2016-11-08, 18:38:42 (66.177.177.194)
I'm loading my 76's in that same range Very sweet indeed! .......
500: Tube DIY Asylum, RE: That's a damn good looking man cave! (0.00)
Posted by deafbykhorns on 2016-11-08, 18:31:02 (66.177.177.194)
Nice work on the breadboard too! .......
Found total of 500 records, Query: , Author: deafbykhorns in All Forums, Time: 1 sec.