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1: Tube DIY Asylum, RE: The 46 a tube so nice i used it twice.... (0.00)
Posted by mwiebe on 2023-09-20, 07:22:28 (77.111.247.57)
Beautiful. Did you use a toroidal interstage? Matt .......
2: MagneQuest/Peerless Forum, RE: Would love to hear some ot those stories... (0.00)
Posted by mwiebe on 2023-03-29, 10:30:12 (77.111.247.233)
Bas, I'll dig around and see what I can come up with. It was mostly in conversation. Matt .......
3: MagneQuest/Peerless Forum, RE: Would love to hear some ot those stories... (0.00)
Posted by mwiebe on 2023-03-28, 14:53:18 (77.111.247.44)
Bas, I'll dig around and see what I can come up with. It was mostly in conversation. Matt .......
4: MagneQuest/Peerless Forum, RE: Mike's passing (0.00)
Posted by mwiebe on 2023-03-27, 06:13:48 (77.111.247.69)
What a rough set of final years Mike went through, but he never let it get in the way good conversation. With me it was motorcycles, bicycles and deep histories of many of the transformers he made. I .......
5: MagneQuest/Peerless Forum, RE: TL-404 , more than one version for impedance taps? (0.00)
Posted by mwiebe on 2023-01-27, 16:46:16 (67.0.226.19)
Ian, For what it is worth here are my TL-404 DCR readings from one autoformer. 1-1 0.7 ohms 1-3 0.9 1-4 0.9 1-5 3.1 1-6 6.9 1-7 11.2 1-8 88.7 So we are essentially the same on our units. The "P" mar .......
6: MagneQuest/Peerless Forum, RE: TL-404 , more than one version for impedance taps? (0.00)
Posted by mwiebe on 2023-01-23, 06:02:14 (67.0.242.229)
Ian, I feel your pain. There were two TL-404 core sizes and a variety of tap, insulation and wire options. And given the requests for tap info for these I'll assume most have nothing written on the co .......
7: Tubes Asylum, RE: Vincent SA-T7 preamp tubes.. (0.00)
Posted by mwiebe on 2021-10-28, 16:36:12 (77.111.247.137)
You are out of luck if you want to plug in your 12a** twin triodes for the tubes you call out. The CV6189 is a single pentode that will probably have substitutes like the E180F, 6J9P, and 6688, which .......
8: MagneQuest/Peerless Forum, RE: BCM11? (0.00)
Posted by mwiebe on 2021-02-24, 06:41:21 (77.111.247.100)
As you point out using the BCM11 with its 100mA current design is not ideal for a plate choke for a 12AX7. The BCP16AG was designed, as Gordon noted, to be used as a plate choke for a 12AX7, 6072. I .......
9: SET Asylum, A Russian 6p21s is not compatible with 6l6, EL34, 6550,KT88 (0.00)
Posted by mwiebe on 2020-12-27, 07:03:45 (77.111.247.4)
Really? Are you suggesting the OP plug in a 6P21S into their MP301 MK3 Deluxe once they have the top-cap sorted? I don't think so. 6P21S has no pin-8 output, the cathode connection on the power tubes .......
10: SET Asylum, Russian 6p21s is a directly heated valve (0.00)
Posted by mwiebe on 2020-12-23, 10:37:09 (77.111.247.66)
The directly-heated 6P21S is not compatible with 6L6, EL34, 6550 etc. These tubes are all indirectly heated. The amp looks like a headphone amp if I understand your reference. You would not want to us .......
11: Tubes Asylum, RE: Varnished copper (magnet?) wire for p2p DIY (0.00)
Posted by mwiebe on 2020-12-02, 15:52:34 (77.111.245.10)
It could be Vampire or Ohno Continuous Cast magnet wire which may or may not be the same thing. It may be difficult to find cast wire in 16 gauge. The quoted text reminds me of Michael Percy who may s .......
12: Tube DIY Asylum, RE: Looking for ready made R-Core transformers... (0.00)
Posted by mwiebe on 2020-01-30, 20:46:55 (77.111.247.68)
Cougar, Here is another possibility but I've never done business with them, http://www.mableaudio.com/en/productview.asp?sid=9033 however Softtone was easy to work with years ago at least. Matt ::: TO .......
13: Tube DIY Asylum, RE: Looking for ready made R-Core transformers... (0.00)
Posted by mwiebe on 2020-01-30, 20:43:16 (77.111.247.68)
Cougar, This maybe a bit over size but your call, .......
14: Tube DIY Asylum, RE: Looking to build an EL-84 power amp (0.00)
Posted by mwiebe on 2018-12-31, 07:32:53 (77.111.246.169)
That is a choke on input, not a transformer, the coil is only on one side. It is there to provide a ground reference for the grid to bias the input tube, just like a more common grid resister. Grid ch .......
15: Tube DIY Asylum, RE: Who has Magnoval sockets? (0.00)
Posted by mwiebe on 2018-11-21, 08:00:08 (77.111.246.46)
The last Cinch Magnoval sockets I got from Leeds Radio but it looks like he is out. There are some listed at Tube World, https://www.tubeworld.com/9pin.htm I'm pretty sure I have some E55Ls plugged in .......
16: High Efficiency Speaker Asylum, RE: great plains audio contact : website err (0.00)
Posted by mwiebe on 2018-08-17, 17:15:32 (77.111.247.71)
Mun, I was having a problem with their website pages loading slow or showing error. I just called Bill yesterday (405) 789-0221 and he is fine. I don't think website maintenance is high on his priorit .......
17: Tube DIY Asylum, RE: Photo (0.00)
Posted by mwiebe on 2017-11-30, 09:45:00 (188.166.58.42)
Thanks again for the info, I should have expected a tube tester would have a socket for these tubes. Still $50 is steep. But it's nice to see what is out there. Anyone know any equipment that spec'ed .......
18: Tube DIY Asylum, RE: Photo (0.00)
Posted by mwiebe on 2017-11-29, 17:35:55 (188.166.7.226)
Thank you for that photo. Do you happen to have the link to where you found it? It's got a Leeds Electric look to it. That socket gives me a 3D printing idea which would be a cleaner solution than wha .......
19: Tube DIY Asylum, 6L4/6F4 tube socket (0.00)
Posted by mwiebe on 2017-11-29, 14:09:29 (188.166.7.226)
I'm looking for sockets for 7-pin acorn tubes like the 6L4 or 6F4. I've used them for years in 5-pin acorn sockets but I've always wondered what a 7-pin acorn socket looks like as I've never seen one .......
20: Tube DIY Asylum, RE: Hook-up wire (0.00)
Posted by mwiebe on 2016-10-13, 07:16:30 (142.0.195.165)
Mouser and I expect other supply sources have plenty of it. .......
21: SET Asylum, RE: Edcor Transformer (0.00)
Posted by mwiebe on 2016-01-07, 19:22:12 (174.28.1.136)
I don't know if that was me or not. I've used both these transformers since Edcor released them. The GXSE5-600-5K has been in daily use for more than five years. They are still so cheap its easier to .......
22: SET Asylum, RE: Pondering DHTs for headphone use (0.00)
Posted by mwiebe on 2016-01-07, 07:53:00 (174.28.1.136)
Thank you for the suggestion. I know they are popular sub-minis but they don't sound as good in the applications I use as do 6088s or the Russians like 1P24B. Matt .......
23: SET Asylum, RE: Pondering DHTs for headphone use (0.00)
Posted by mwiebe on 2016-01-05, 14:47:52 (174.28.1.136)
Jim, I mostly listen to DHTs and headphones (Beyer 600ohms) and Magnequest TL-404, a 2W rated autoformer, so you have to run a DC blocking cap. The TL-404 has taps at both speaker level (4,8,16,32) an .......
24: MagneQuest/Peerless Forum, RE: What's spec's of TL-404 XL? (0.00)
Posted by mwiebe on 2015-09-12, 19:33:08 (174.28.28.72)
Joe, I know we are talking about real power now. But given Mike's conservatism the 404 is probably good for real world 3Ws anyway, and the XL is probably good for 4Ws. I'm building an amp for a colle .......
25: MagneQuest/Peerless Forum, RE: What's spec's of TL-404 XL? (0.00)
Posted by mwiebe on 2015-09-09, 18:41:37 (174.28.28.72)
Mike, So instead of a 2W rating it's 2.6W? What is the application that benefits from that little boost? Matt .......
26: MagneQuest/Peerless Forum, What's spec's of TL-404 XL? (0.00)
Posted by mwiebe on 2015-09-09, 11:37:40 (174.28.28.72)
Mike, I hope you had a great vacation. You've got me wondering about those TL-404XLs. Can you provide a link to more info on those? Are they C-core? Thanks, Matt .......
27: Tube DIY Asylum, RE: Pinging Paul Joppa or anyone else that can (0.00)
Posted by mwiebe on 2015-01-25, 17:01:25 (174.28.3.149)
Xaudiomanx, A search of the Magnequest forum here turned up this. Matt .......
28: Tube DIY Asylum, RE: Cost-Effective Cathode Chokes (0.00)
Posted by mwiebe on 2015-01-18, 16:31:59 (174.28.13.244)
I've used the same Edcor in an "SRPP" between triodes with cathode follower drive, but I cannot find my schematic of that. I've also used some Hammond 1628 as cathode chokes in A2 designs, open second .......
29: Tube DIY Asylum, RE: Cost-Effective Cathode Chokes (0.00)
Posted by mwiebe on 2015-01-18, 09:50:09 (174.28.13.244)
This has always worked fine for me. Granted using the little Edcor I don't push many mA through it but it works just like it should. The primarly is open. Matt .......
30: Tube DIY Asylum, RE: Can I use a resistor instead of the choke for coupling to the 813? (0.00)
Posted by mwiebe on 2014-10-29, 14:47:50 (174.28.23.113)
Vinnie, You have to know the operating points you want to run the power half of the 6EM7 in order to figure out what you need as a decoupler. For example lets say you want to run 150Vs from plate to c .......
31: Tube DIY Asylum, RE: Q About Edcor Transformer Performance (0.00)
Posted by mwiebe on 2014-10-26, 11:10:14 (174.28.23.113)
TK, The GXSEs are probably your best bet, but you probably do not want to hear that the 5K/600 sounds quite a bit better then the 15K version. In trying headphones of different impedances on the tu .......
32: Tube DIY Asylum, RE: Q About Edcor Transformer Performance (0.00)
Posted by mwiebe on 2014-10-25, 13:08:56 (174.28.23.113)
TK, I have not measured the response of any Edcors in my headphone amps. But I have used quite a few in headphone amps. Not knowing the tube you wish to use, plate current, power output, headphone im .......
33: SET Asylum, ELROG 300B (0.00)
Posted by mwiebe on 2014-10-09, 16:14:43 (174.28.23.113)
It's not an EML 300B but Thomas Mayer just announced they are starting production. They appear to have standard 300B parameters. I know nothing about them beyond what is on Thomas' site. With the Taka .......
34: Tube DIY Asylum, Brainiacs (0.00)
Posted by mwiebe on 2014-05-09, 07:01:01 (174.28.11.62)
I've only seen the Brainiacs once and I really like their form factor, they are pretty and Mike speaks highly of them. My 300b has TFA-2004 Sr. and FS100 Plate Chokes gapped for 80ma, a setup visually .......
35: Tube DIY Asylum, Even more plate chokes (0.00)
Posted by mwiebe on 2014-05-08, 13:34:38 (174.28.11.62)
Mike, Just to give your huge line of magnetic offerings a further plug--I don't think anyone has a FULL list of what Mike has on offer and take him at his word he can wind most anything. Here are a fe .......
36: Tube DIY Asylum, RE: Loftin white 2a3 with CCS on 2a3 (0.00)
Posted by mwiebe on 2013-12-06, 13:57:58 (174.28.139.162)
This could be closer to what you are looking for, http://www.diyaudio.com/forums/tubes-valves/188698-best-set-design-2.html#post2566741 You could replace the choke over the power tube, in this example .......
37: Tube DIY Asylum, Sorry wrong Darius link, here is his home page on this (0.00)
Posted by mwiebe on 2013-12-05, 12:51:14 (174.28.139.162)
.......
38: Tube DIY Asylum, RE: Loftin white 2a3 with CCS on 2a3 (0.00)
Posted by mwiebe on 2013-12-05, 12:47:28 (174.28.139.162)
To suggest an answer you would need to share your schematic. There is a lot that calls itself Loftin White but is simply direct connect topology. There is a lot of very clever thinking going on with a .......
39: MagneQuest/Peerless Forum, RE: B7 15K/600 ohm and ceramic GS-24B (0.00)
Posted by mwiebe on 2013-10-05, 09:18:24 (174.28.5.101)
Mike, I was just playing around developing a 2-stage highish power SET with cheap "dht" tubes. The Russian ceramics are perfect for that and sound great. The GS-24B and your B7 is a pretty good headph .......
40: SET Asylum, RE: what do you guys think of the James HS123s? (0.00)
Posted by mwiebe on 2013-09-20, 10:01:00 (174.28.129.179)
The JS-6123HS is extremely good, great bass. I've used them with 2A3, 300B and SV811-10 (running A2). Plenty have written about this exact transformer on this site, so lots of opinions via search. Jam .......
41: MagneQuest/Peerless Forum, B7 15K/600 ohm and ceramic GS-24B (0.00)
Posted by mwiebe on 2013-09-08, 09:41:27 (174.28.28.215)
Here is a totally useless data point, but I’m passing it on anyway. The tube is a Russian ceramic GS-24B, running with a plate voltage of 158V, output transformer is B7-15K/600ohms, plate choke i .......
42: Tube DIY Asylum, RE: anode cap for 6CB5A (0.00)
Posted by mwiebe on 2013-09-07, 18:03:44 (174.28.27.2)
I just solder to the plate cap as well. Its 3/8" as has been suggested the Millen are a no brainer. But if you are looking for a stylistic look, and you don't have children or pets, the Bud metal caps .......
43: Tube DIY Asylum, RE: Tube L bracket (0.00)
Posted by mwiebe on 2013-09-02, 06:48:48 (174.28.27.2)
I'm sorry it is not an octal. I wish I could find an octal version of this. Like others, for octals it's aluminum angle. Matt .......
44: Tube DIY Asylum, RE: Tube L bracket (0.00)
Posted by mwiebe on 2013-09-01, 16:19:13 (174.28.27.2)
Apex Jr. has right angle 9-pins that I use a lot. http://www.apexjr.com/Sockets.htm .......
45: Tube DIY Asylum, RE: new (to me) Russian PIO capacitor on ebay (0.00)
Posted by mwiebe on 2013-08-05, 21:19:15 (75.173.6.194)
The K40s never sounded at good as the FT-3 teflons to me. But it's cheap enough to try and find what works in your circuit, that's really the best guide. Matt .......
46: Tube DIY Asylum, RE: new (to me) Russian PIO capacitor on ebay (0.00)
Posted by mwiebe on 2013-08-05, 19:51:25 (75.173.7.78)
I've only tried them in values >1uF and they are no KGB-MN. But they are better than other K75 types I have tried, just a little sibilant edge. They are so inexpensive I would give them a try. They ha .......
47: MagneQuest/Peerless Forum, FS-100 is a plate choke to match FS-100PF (0.00)
Posted by mwiebe on 2013-06-01, 19:03:40 (75.173.4.25)
It's easy to get confused on this series. FS-100 came in a series of plate chokes originally designed for the FS-100PF, a parallel feed SE output.. There also is a FS-100 series feed SE output. If you .......
48: Tubes Asylum, KR T-1610 is a triode (0.00)
Posted by mwiebe on 2013-05-29, 19:30:24 (75.173.4.25)
Since the video is showing mostly KR Audio tubes, the big tube is probably KR's giant T-1610 triode. $2,500 a pair. Matt .......
49: Vinyl Asylum, Article on Pete Hutchison and Electric Recording Company (0.00)
Posted by mwiebe on 2013-05-25, 18:03:13 (75.173.4.25)
http://www.guardian.co.uk/music/2013/may/25/pete-hutchison-interview-new-vinyl-recording .......
50: MagneQuest/Peerless Forum, RE: BAC-80 questions (0.00)
Posted by mwiebe on 2013-05-22, 13:57:28 (75.173.4.25)
Dan, Not to confuse things but I use a FS-100 (gapped 80ma/105H) with a TFA-2004 Senior, which is a great combination for 300B. I have never heard the BAC-80. The FS-100 is also bobbin wound but I'm s .......
51: Tube DIY Asylum, RE: 829B Sockets (0.00)
Posted by mwiebe on 2013-02-25, 21:01:14 (75.173.0.201)
Triode Kingdom, I've used quite a few of them and I've had no problems. The "teflon" isn't as soft as other teflon sockets I've used, kind of hard like the UK NOS loctal teflon sockets if you have use .......
52: MagneQuest/Peerless Forum, RE: Red, Black lead chokes, which is dot? (0.00)
Posted by mwiebe on 2013-02-20, 08:53:29 (75.173.0.201)
Paul, Maybe it is Mike’s low-capacitance windings but I didn’t have much difference between red and black wires with my capacitance meter, but red lead was always a touch lower in capacitance. I know .......
53: MagneQuest/Peerless Forum, RE: Red, Black lead chokes, which is dot? (0.00)
Posted by mwiebe on 2013-02-17, 06:12:05 (75.173.4.48)
Mike, So if black is AC ground, then Red should be the winding start, correct? I'm just curious. Thanks, Matt .......
54: MagneQuest/Peerless Forum, Red, Black lead chokes, which is dot? (0.00)
Posted by mwiebe on 2013-02-16, 07:12:18 (75.173.4.48)
Does anyone know? Thanks, Matt .......
55: Tube DIY Asylum, RE: My ideas on this... (0.00)
Posted by mwiebe on 2013-02-11, 19:42:06 (75.173.4.48)
Triode Kingdom, Interesting idea. How are you going to get the gain you need? The little Edcor WSMs do a good voltage step up for cheap. I assume whatever is driving the amp can overcome Miller. I'm n .......
56: Tube DIY Asylum, RE: Headphone Transformers (0.00)
Posted by mwiebe on 2013-02-11, 09:56:54 (75.173.4.48)
Triode Kingdom, I can only comment on GXSE5-600-5K and GXSE5-600-15K that I use for line stage outputs. In my use I have never gotten close to 5W, mostly 150V/20mA or about 3W. They have plenty of ba .......
57: Tube DIY Asylum, RE: Headphone Transformers (0.00)
Posted by mwiebe on 2013-02-10, 18:53:49 (75.173.4.48)
Triode Kingdom, It gets down to how much you want to pay, series feed or parallel. Electra Print has 10K/32ohm that I expect Jack would work with you to get closer to what you want. Magnequest EXO- .......
58: Tube DIY Asylum, RE: 6 pin DIN plug (0.00)
Posted by mwiebe on 2013-01-11, 06:54:44 (75.173.6.173)
I have used these slightly different Neutrik connectors with 18g wire for years, up to 500V with no problems whatever. Lock into place nicely and work without a hitch. .......
59: Tubes Asylum, Sweet, Thanks so much for sharing that (nt) (0.00)
Posted by mwiebe on 2012-11-11, 10:25:45 (75.173.0.34)
.......
60: Tube DIY Asylum, 717A, 6SJ7 (nt) (0.00)
Posted by mwiebe on 2012-08-21, 13:32:55 (75.173.2.140)
.......
61: Radio Road, RE: Miniature Tuner? (0.00)
Posted by mwiebe on 2012-08-10, 15:53:19 (75.173.7.68)
I was going to suggest an auto tuner since many have pre-amp outputs, so you could still use your amp. But they are ugly without a box and you will still need a power supply of some sort. Rigging the .......
62: Radio Road, RE: Miniature Tuner? (0.00)
Posted by mwiebe on 2012-08-10, 07:48:50 (75.173.7.68)
I don’t know the form size you are looking for but the Sony xdr‑f1hd or ICF-SW100 are small but not cheap. The Pro-Ject tuner box is a little smaller. TEAC AG-H380DAB is a receiver, it’s small b .......
63: MagneQuest/Peerless Forum, RE: Mike, What is this Magnequest line-output? (0.00)
Posted by mwiebe on 2012-06-02, 15:17:47 (75.173.5.161)
Paul, I would be the first to admit my knowledge of Magenquest's extensive catalog is limited. So given your post I started searching for the spec's on a series feed FS-100, and only came up with this .......
64: MagneQuest/Peerless Forum, RE: Mike, What is this Magnequest line-output? (0.00)
Posted by mwiebe on 2012-04-25, 05:44:24 (75.161.74.14)
Mike, Was unaware you made series feed line outputs, so thanks for the information. Matt .......
65: MagneQuest/Peerless Forum, Mike, What is this Magnequest line-output? (0.00)
Posted by mwiebe on 2012-04-24, 08:42:19 (75.161.74.14)
Mike, In the Audio Asylum Trader someone is selling something titled "Magnequest Multitap Custom Line Out Transformers". They do not look like your parallel feed outputs, B7 or TL-404, but I'm not fam .......
66: Tube DIY Asylum, RE: Just be really patient. (0.00)
Posted by mwiebe on 2012-04-20, 07:00:19 (75.161.74.14)
Dan, I've had good luck mounting the 6EM7 over a choke, cathode driving A2 grids. Cheaper and another option that works very well. Matt .......
67: Tube DIY Asylum, RE: 6L6 amp like the PP47? (0.00)
Posted by mwiebe on 2012-04-19, 18:23:48 (75.161.74.14)
GSH, You might want to look at the Fi Primer 6CK4 PP for a really simple schematic along these lines, http://tinpan.fortunecity.com/saints/668/primer/6ck4-pp.gif You can forgo the phase splitting inpu .......
68: Radio Road, RE: Internet Radio (0.00)
Posted by mwiebe on 2012-04-10, 17:51:59 (75.173.5.115)
I'm not really sure what you are asking. I use TuneIn on an Ipod Touch in an Wadia 170i dock. It provides analog or digital output (S/PDIF Coax). If I was looking for something at a lower cost I would .......
69: Tube DIY Asylum, RE: 6S17K planer to GU-15 (0.00)
Posted by mwiebe on 2012-03-23, 07:03:34 (75.173.5.115)
Ray, I really like your "socket" for the tube, would make sorting easy. You would think with as many surplus planer tubes there would be a handful of surplus sockets as well. Swapped in a Magnequest E .......
70: Tube DIY Asylum, RE: 6S17K planer to GU-15 (0.00)
Posted by mwiebe on 2012-03-23, 06:41:19 (75.173.5.115)
They are nothing like nuvister tubes, thankfully--they are extremely non-microphonic. Do an ebay search for 6S17K to see what they look like. They are like US tubes like 6299, 7077, 7266, 8906 etc. bu .......
71: Tube DIY Asylum, 6S17K planer to GU-15 (0.00)
Posted by mwiebe on 2012-03-22, 10:26:32 (75.173.5.115)
Just playing around with a two-stage “DHT” using 6S17K-V planer tubes cap coupled to a trioded GU-15. I had been using a 6L4 acorn as a driver, so I just popped it out and clip-leaded the 6S17K in. So .......
72: MagneQuest/Peerless Forum, RE: EXO-01 Plate load chokes (0.00)
Posted by mwiebe on 2012-03-17, 14:50:50 (75.173.5.115)
John, This may get you started until Mike responds. I know these can be gapped but this is the "stock" spec' I think 10 madc 275 henries dcr approx 825 ohms. Max ac: 245 volts at 20 hertz Matt ::: TOP .......
73: Tube DIY Asylum, RE: 6L4p should be 4L1P, (nt) (0.00)
Posted by mwiebe on 2012-03-16, 18:31:36 (75.161.75.54)
Aldovan, I think that is just a 9-pin loctal base. I've used these from Ned, http://www.tubezone.net/9-Pin-Loctal-Ceramic-Chassis-Socket_p_116.html, before for tubes with 9-pin loctals. But I'm not fa .......
74: Tube DIY Asylum, RE: 4L1P should be 4P1L (nt) (0.00)
Posted by mwiebe on 2012-03-16, 18:24:33 (75.161.75.54)
Andy, I'm so dyslexic it's surprising I know which side of the bed to get up from. But you're right, no matter what I call them they are a nice sounding tube. Matt .......
75: Tube DIY Asylum, 6L4p should be 4L1P, (nt) (0.00)
Posted by mwiebe on 2012-03-16, 10:33:39 (75.161.75.54)
.......
76: Tube DIY Asylum, Hammond (0.00)
Posted by mwiebe on 2012-01-16, 12:51:31 (75.161.66.9)
Hammond makes a few, http://www.hammondmfg.com/HWCHAS.htm http://www.hammondmfg.com/dwg20CWW.htm http://www.hammondmfg.com/dwg21CWW.htm Matt .......
77: Radio Road, My 8-year old son did (0.00)
Posted by mwiebe on 2011-12-24, 06:36:24 (75.161.66.9)
VoltSecond, It was a very simple kit to put together. It's been years so I don't really remember what was involved. He still uses it and enjoys it's portability . The "horn" speakers are quite fragile .......
78: MagneQuest/Peerless Forum, I second TL404 request (0.00)
Posted by mwiebe on 2011-11-22, 15:00:22 (75.173.1.173)
Mike, I'm also interested in TL-404 versions. Matt .......
79: SET Asylum, Millett Jonokuchi (0.00)
Posted by mwiebe on 2011-11-16, 17:49:41 (75.173.1.173)
I bet the Jonokuchi could be built to that budget. While I know the tube well I have no experience with the Jonokuchi. Matt .......
80: Radio Road, RE: does anyone make such a thing? (0.00)
Posted by mwiebe on 2011-09-20, 13:17:44 (75.161.67.33)
Since you are recording digitally anyway I would suggest the $0.99 Tunein app for an itouch, iphone and maybe others. It allows you to tune into most any FM or AM station anywhere in the world that st .......
81: MagneQuest/Peerless Forum, RE: PP 6EM7 schematic (0.00)
Posted by mwiebe on 2011-08-23, 19:26:16 (75.173.4.63)
Keto, Thanks for sharing. I've got a similar design I'm working on with input phase splitting 1:1. The plate loads for the input has me taking pause. I don't want to use a pair of EXO-99s and I wonder .......
82: Tube DIY Asylum, RE: Need a preamp for brother (0.00)
Posted by mwiebe on 2011-03-25, 21:31:44 (75.161.71.165)
Dan, XSM if you want an easier solution. I'm not sure I would pick a parafeed cap at this point, you may need to tweak that to taste. In my Magnequest TL-404 pre I rotate between Russian K-75s, Audioc .......
83: Tube DIY Asylum, RE: Need a preamp for brother (0.00)
Posted by mwiebe on 2011-03-25, 21:03:11 (75.161.71.165)
Dan, You can bring the gain down by using a lower mu tube or cathode drive, as I'm sure you know. The GXSE5-600-5K is a very nice output trans. If you are shooting for a buffer there are other ways of .......
84: Tube DIY Asylum, RE: Need a preamp for brother (0.00)
Posted by mwiebe on 2011-03-25, 20:19:13 (75.161.71.165)
Dan, I'm not sure about the cap couple or the SRPP before the output transformer. This Edcor, GXSE5-600-15K, takes a bit of current, easily 10ma. The GXSE5-600-5K sounds better and you can use anythin .......
85: MagneQuest/Peerless Forum, RE: Hi Matt, it's a Magnequest coating....I got a choice (0.00)
Posted by mwiebe on 2011-02-23, 10:53:53 (75.161.94.199)
Mike, Fair enough its now discontinued. My vote that it's a nice option. Matt .......
86: MagneQuest/Peerless Forum, RE: RIT 5 coating (0.00)
Posted by mwiebe on 2011-02-23, 07:34:01 (75.161.94.199)
Bas, Is that a coating you did or a Mangequest option/standard? Sure looks nice. Matt .......
87: Tube DIY Asylum, RE: To reduce the gain of my new Monarchy SE160 poweramp, can I simply... (0.00)
Posted by mwiebe on 2011-02-22, 06:40:13 (75.161.94.199)
Without knowing the schematic it is hard to say. There is always swapping in a 12AU7 or similar, bypassing a gain stage or putting a voltage tap on input. You could always try a passive preamp, or a n .......
88: Tube DIY Asylum, RE: Has anyone tried parafeed 845? (0.00)
Posted by mwiebe on 2011-01-12, 12:19:17 (75.173.5.187)
Magnequest produced a run of iron to do just that, parallel feed transmitter tubes. The outputs are FS100 PF, spec'ed 10,000 ohm primary, 4,8, and 16 ohm secondary 30 watts at 15 hertz, primary DCR 27 .......
89: SET Asylum, RE: Driver tube choice for GM70 (0.00)
Posted by mwiebe on 2010-09-06, 14:22:33 (75.173.4.120)
If you are interested in a two-stage GM70, Andrea Ciuffoli has done a few with Da3, http://www.audiodesignguide.com/Claudio845/845amp.html and with 6HV5A http://www.diyaudio.com/forums/tubes-valves/13 .......
90: Tube DIY Asylum, Spice on Mac (0.00)
Posted by mwiebe on 2010-08-30, 14:39:13 (75.161.89.17)
Andy, It's possible to run LTSpice on a Mac without bothering with Windows. Check out Crossover software from Codeweavers. You can run Duncan's PSUD as well. The trial version is free. Once you get it .......
91: DIY HiFi Forum, KEF's take (0.00)
Posted by mwiebe on 2010-07-24, 13:02:05 (75.161.85.18)
Brian, From experience it pays to pay attention to the different B110s and the model you need to replace. KEF pretty much lays it out, http://www.kef.com/ca/about/ls35a As you can see B110 doesn't des .......
92: Tubes Asylum, RE: Lowering bias on a fixed bias amp? ;^) (0.00)
Posted by mwiebe on 2010-05-24, 06:03:16 (75.161.93.133)
It would be easy to check those caps for leakage. It sounds like the issue here was slightly higher B+. If the caps were leaking DC that would increase plate current a bit. Matt .......
93: Tubes Asylum, RE: Lowering bias on a fixed bias amp? ;^) (0.00)
Posted by mwiebe on 2010-05-23, 19:15:38 (75.161.93.133)
Lars, There are voltage readings on that schematic so you can check if your mains voltage has bumped things up, I expect there is a good chance of that. The 6P14P-EV is nice and plugging those in woul .......
94: Tubes Asylum, RE: Lowering bias on a fixed bias amp? ;^) (0.00)
Posted by mwiebe on 2010-05-23, 14:37:46 (75.161.93.133)
Lar, This is a direct-coupled amp, so it uses a tuned combination of cathode bias, R3, R4, R11 and R12 and driver plate voltage to set power tube grid bias that are in no way fixed. There is a lot go .......
95: MagneQuest/Peerless Forum, RE: .... note for Matt and other FS-100 Plate Choke users.... (0.00)
Posted by mwiebe on 2010-04-09, 15:32:58 (75.161.94.90)
Mike, We are building in a tower so height is not a problem. We did consider horizontal mounting, but those chokes are so heavy the mounting feet distort a bit. Your layer wound TFA-2004 Juniors still .......
96: MagneQuest/Peerless Forum, RE: High inductance 55/60mA plate choke (0.00)
Posted by mwiebe on 2010-04-09, 09:37:33 (75.161.94.90)
Well Phil and I are working on a 2A3 amp, nickel TFA-2004 Jrs and FS100 Plate Chokes gapped for 80ma. Those little outputs next to the FS100s look real out of place. I'm also in camp that likes the so .......
97: Tube DIY Asylum, RE: silver mica caps (0.00)
Posted by mwiebe on 2010-04-07, 13:20:00 (75.161.81.81)
On ebay, http://cgi.ebay.com/0-1uF-500V-Silver-Mica-Capacitors-KSG-2-Lot-24-NEW_W0QQitemZ390161928826QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad776927a Or double up these, http://cgi.ebay.com/S .......
98: MagneQuest/Peerless Forum, RE: Where did you get the corner extrusions? (0.00)
Posted by mwiebe on 2010-02-18, 17:21:33 (75.161.73.246)
Paul, I never noticed Front Panel Express offers those, thanks for pointing that out. Now if Front Pannel Express would add a Mac program I'll be set. I do like how you did it with the flush front, th .......
99: MagneQuest/Peerless Forum, Where did you get the corner extrusions? (0.00)
Posted by mwiebe on 2010-02-18, 13:04:02 (75.161.73.246)
That looks nice. I'm assuming the corner pieces receive the top and side plate. I've been looking for that type of an extrusion for awhile. Where did you source them? Matt .......
100: Tube DIY Asylum, RE: Anyone heard these? (0.00)
Posted by mwiebe on 2010-02-16, 19:53:20 (75.161.73.246)
I've got a pair and I used them off and on for three years. They are not as cheap as you think, shipping is quite a bit. I had one that didn't survive the trip, so I had to order one more. They are ok .......
101: Tube DIY Asylum, RE: Spud amp with the 6HS5 (0.00)
Posted by mwiebe on 2010-02-06, 10:24:09 (75.161.73.33)
Thomas, Thanks for the info. Do you have a website for your comercial business? For some reason I cannot google it up. Matt .......
102: Tube DIY Asylum, RE: Spud amp with the 6HS5 (0.00)
Posted by mwiebe on 2010-02-06, 10:02:28 (75.161.73.33)
Thomas, The 60H/40ma chokes have a “For Thomas Mayer” designation, are these chokes you sell or Lundahl? What ultrapath cap are you using NOS, Russian or current manufacturer? I’ve .......
103: Tube DIY Asylum, RE: Can I light only half the filaments of a dual triode? (0.00)
Posted by mwiebe on 2010-02-05, 14:17:53 (75.161.73.33)
I've run them 1/2 way for years with no problems. As you have already figured out, if you light the opposite halfs for a stereo amp you can just swap the 3A5s from side to side to light up the "new" h .......
104: Tube DIY Asylum, RE: 4V rectifiers (0.00)
Posted by mwiebe on 2010-02-03, 06:51:49 (75.161.73.33)
Theo, 3DG4 can easily deliver 100ma. Fil is 3.3V/3.8a Matt .......
105: Tube DIY Asylum, RE: OT: Instrument solder (0.00)
Posted by mwiebe on 2010-01-20, 06:57:16 (75.161.69.119)
The water key was in the wrong place from a previous repair and it bugged me, that's why I broke it off and repositioned it, now it hits the cork just right. Well reading on the net I saw people using .......
106: Tube DIY Asylum, OT: Instrument solder (0.00)
Posted by mwiebe on 2010-01-19, 20:16:34 (75.161.77.8)
I hate to break in, but as I had to fix the spit valve on my boys trumpet today I had to ask. I did the repair with Kester Sn/Ag/Cu and it appears solid, but is there a standard solder you all use? My .......
107: Tube DIY Asylum, RE: Everything Gets a Bad Rap (0.00)
Posted by mwiebe on 2010-01-14, 21:55:44 (75.161.77.8)
I agree with Triode Kingdom. I expected the transition A1/A2 to sound as we’re not working with zero impedance, but it seems like the opposite, the music sounds freer--the reverse of “stru .......
108: Tubes Asylum, RE: miniwattamp tubes (0.00)
Posted by mwiebe on 2009-12-12, 15:10:35 (75.161.77.8)
Howie, I don't have that amp, but I think the 6P1 Shuguang and the Russian 6P1P (6P1P-EV) look to be plug in compatible. 6P1P are cheap, just get a '70s or early '80s version. 6V6 is an octal so it w .......
109: Vinyl Asylum, RE: generic source for silicone tonearm fluid? (0.00)
Posted by mwiebe on 2009-12-11, 18:56:57 (75.161.77.8)
Just google "silicone tonearm fluid" and you will find sources. Matt .......
110: Tube DIY Asylum, RE: Rimlock adapter? (0.00)
Posted by mwiebe on 2009-11-10, 12:07:19 (75.161.89.91)
Rimlock bases come in a few different versions as do 9-pin so its a little hard to say if they are bolt-in replacements, some are too big some are too small. As for an adapter I wired up a rimlock bas .......
111: Tube DIY Asylum, RE: Edcor WSM 600/600 wiring question, project schematic shown (0.00)
Posted by mwiebe on 2009-11-08, 18:04:06 (75.161.89.91)
Joe, If those little dots you have in your model are the start ends of the coil, you may want to try flipping the secondary of that tranny over the 5687 plate so the “dot” goes to the gri .......
112: Tube DIY Asylum, Steve at ApexJr says he has 100s of these sockets (nt) (0.00)
Posted by mwiebe on 2009-10-14, 09:18:07 (75.161.95.35)
.......
113: Tube DIY Asylum, Perfect and Thanks, I hope they have them in stock (nt) (0.00)
Posted by mwiebe on 2009-10-13, 21:17:09 (75.161.95.35)
.......
114: Tube DIY Asylum, RE: Sourcing 9-pin horizontal sockets (0.00)
Posted by mwiebe on 2009-10-13, 12:51:02 (75.161.95.35)
Yea but using the correct socket is so much easier. I bought 30 of these years ago and I'm down to my last 4. They are so easy to use I would like to stock up again. Mine were from Oneida Electroni .......
115: Tube DIY Asylum, Sourcing 9-pin horizontal sockets (0.00)
Posted by mwiebe on 2009-10-13, 08:56:14 (75.161.94.91)
I'm looking for 9-pin minature 90-degree sockets. Anyone know where I can find some? Thanks, Matt .......
116: MagneQuest/Peerless Forum, RE: 6EW7_2A3 Parafeed PP (0.00)
Posted by mwiebe on 2009-10-06, 13:46:47 (75.161.94.91)
John, Since you want to listen to a few options with this topology you are limited on the hi-mu plate voltage. I usually run this up around 180-200Vpk around 5ma but I’m not sure how to do this .......
117: MagneQuest/Peerless Forum, RE: 6EW7_2A3 Parafeed PP (0.00)
Posted by mwiebe on 2009-10-06, 11:51:28 (75.161.94.91)
John, I’ve used a few 6EW7s, but none as a P-P driver like you have. What is your plate to cathode voltage on the high mu triode and the lo-mu triode? I expect there is a bit of voltage drop ov .......
118: Tubes Asylum, RE: Help read 6P1P-EV Russian data sheet (0.00)
Posted by mwiebe on 2009-10-01, 14:56:25 (75.161.95.33)
I'm not sure what you are looking for exactly, but this link might help? Matt .......
119: MagneQuest/Peerless Forum, RE: TL-404 is an autoformer (0.00)
Posted by mwiebe on 2009-09-15, 19:24:13 (75.161.84.28)
Chris, That is not the schematic symbol for an autoformer, use the symbol of a choke if you have it. It's important to get it right visually because it reminds you there is no isolation of any kind in .......
120: MagneQuest/Peerless Forum, TL-404 is an autoformer (0.00)
Posted by mwiebe on 2009-09-15, 17:16:43 (75.161.84.28)
Chris, The way you have the output wired will not work. Matt .......
121: SET Asylum, RE: What's the cheapest decent OPT for a SE 300b? (0.00)
Posted by mwiebe on 2009-09-11, 13:08:09 (75.173.3.188)
Not to thread jack, but did you actually receive your #1 Edcor suggestion? I would be curious to hear what you thought of the combo. Matt .......
122: Tube DIY Asylum, RE: DIY clips for octal base pins? (0.00)
Posted by mwiebe on 2009-09-02, 05:05:10 (75.161.77.155)
Dogwan, Here is a socket that might work, scroll down to (TUA) 77MIP-9S. Leeds Electronics may also have what you need, http://leedsradio.com/parts-sockets.html Amphenol MIP 9 (same pin circle as octa .......
123: Tube DIY Asylum, http://groups.yahoo.com/group/gm70/ (0.00)
Posted by mwiebe on 2009-08-19, 07:24:09 (75.173.5.192)
Bas, If your focus is on GM70 power supplies you might want to read the archive of this group. Lots of suggestions and schematics to think about. Matt .......
124: Tube DIY Asylum, 6CJ3 (0.00)
Posted by mwiebe on 2009-08-18, 15:05:09 (75.173.5.192)
Bas, This is one of my favorites but there are plenty of other 6.3V that handle the voltage, remeber to float or raise the heater voltage and most are single plate so you will probably need two. Just .......
125: K&K Audio / Lundahl Transformers, Thanks, I'll look at the bigger ones (nt) (0.00)
Posted by mwiebe on 2009-08-15, 15:05:51 (75.173.5.192)
.......
126: K&K Audio / Lundahl Transformers, RE: Suggestions on amp input phase splitter (0.00)
Posted by mwiebe on 2009-08-14, 21:24:11 (75.173.5.192)
Kevin, 20V would be max, I expect it will mostly be at 6 to 10V so consider this to be the input range. I use an active preamp so my amps are low gain. Thanks, Matt .......
127: Tubes Asylum, My mistake on 6N3P, memory moment (nt) (0.00)
Posted by mwiebe on 2009-08-14, 12:46:35 (75.173.5.192)
.......
128: Tubes Asylum, RE: Lets analyze closely what I said. (0.00)
Posted by mwiebe on 2009-08-14, 11:22:21 (75.173.5.192)
Don, There is no such 6N3C-E Russian power tube, these English letters refer to a Russian twin-triode. From the first post you can see that the tube discussed is to replace a US type 6L6GC. The Russi .......
129: K&K Audio / Lundahl Transformers, Suggestions on amp input phase splitter (0.00)
Posted by mwiebe on 2009-08-13, 17:51:55 (75.173.5.192)
It seems like the LL1540, LL1544A, LL1591, LL1592, LL1676 and LL1690 will all work as input phase splitters. The LL1591 is the splitter with the stock ST-70 board, the LL1544A the upgrade for that sam .......
130: Bottlehead Forum, RE: EF40 "Sub" For EF86 In Eros?--Doc/PJ/Paul Et.Al. (0.00)
Posted by mwiebe on 2009-07-22, 06:55:58 (75.173.0.8)
Grainger, The EF40 is as similar to an EF86 as your 7N7 is to a 6SN7. If you properly rewire the socket it works great. The bases are easy to find but are slightly larger then the small 9-pins, so you .......
131: MagneQuest/Peerless Forum, RE: Hey Mike, how about this idea? (0.00)
Posted by mwiebe on 2009-04-30, 11:27:47 (75.161.94.152)
Keto, Only answering your Q 4. I built my preamp for a 26 using a 15K B7 (M6) output and I put the plate choke on jumpers so I could switch between a variety of Mike’s plate chokes. I agree wit .......
132: Radio Road, RE: Sherwood S-3000 II tube list? (0.00)
Posted by mwiebe on 2009-04-24, 16:36:02 (75.161.81.21)
No worries but you need a sense of humor with Sherwood. As you noticed my Ser. # is below 936000 yet my tube complement matches Sherwood schematics over that Ser. #. Your S-3000 II should match that 9 .......
133: Radio Road, RE: Sherwood S-3000 II tube list? (0.00)
Posted by mwiebe on 2009-04-24, 13:18:00 (75.161.81.21)
No worries but you need a sense of humor with Sherwood. As you noticed my Ser. # is below 936000 yet my tube complement matches Sherwood schematics over that Ser. #. Your S-3000 II should match that 9 .......
134: Radio Road, RE: Sherwood S-3000 II tube list? (0.00)
Posted by mwiebe on 2009-04-24, 06:10:12 (75.161.81.21)
The number on my S-3000II is 935815. They could have switched to a 6GN8 at some point in the series, but as I mentioned my tube line up is the same as yours except for the 12AZ7 difference. Matt ::: T .......
135: Radio Road, RE: Sherwood S-3000 II tube list? (0.00)
Posted by mwiebe on 2009-04-23, 12:48:04 (75.161.81.21)
You probably know Sherwood changed circuits when they found improvement rather then at model changes. That said my S-3000 II has a 12AZ7 in place of your 12AT7. The S-3000 II schematic I have shares y .......
136: Tube DIY Asylum, RE: L3, L4 (0.00)
Posted by mwiebe on 2009-04-21, 06:41:38 (75.161.81.21)
I expect you can get away with AC heaters but you may have hum. Look over other phono preamp filament supplies and see what is used most often, that would be your best bet. Tube rectifiers don't have .......
137: Tube DIY Asylum, RE: L3, L4 (0.00)
Posted by mwiebe on 2009-04-20, 17:47:48 (75.161.81.21)
I expect you are talking about a common mode choke for which both legs, plus and minus, share the core. This type of choke is not identified in the schematic. A common mode choke addresses common mode .......
138: Tube DIY Asylum, L3, L4 (0.00)
Posted by mwiebe on 2009-04-20, 16:29:13 (75.161.81.21)
I'm not sure what you are trying to do with these? It looks like you are wanting to run AC heaters on a phono preamp for some reason. I expect you may end up going to DC but what do I know. I doubt th .......
139: Tube DIY Asylum, RE: Stacked supplies - what does this phrase mean? (0.00)
Posted by mwiebe on 2009-04-11, 09:07:26 (75.161.90.139)
You have two different power supplies. The ground of one supply is hooked to the high-voltage end of the other supply. So they end up stacked one on the other. It is like bucking or boosting using tap .......
140: Tube DIY Asylum, RE: Solen SM polypropylene & tin foil (0.00)
Posted by mwiebe on 2009-04-02, 10:20:37 (75.161.64.112)
A search for "tin" AND "Solen" turns up 78 results, "tin" and "SCR" 56, with lots of crossover. I use them as couplers and really like them, not so much as a parallel feed blocking cap. Matt ::: TOPIC .......
141: Radio Road, RE: Scott 350B Power Supply (0.00)
Posted by mwiebe on 2009-03-12, 19:49:25 (75.173.1.226)
Dave, Eli's method is the cleanest suggestion. I have the same tuner, 350B, and caps are so small now I just fit them in around the base of the multi-cap. they fit just fine. Getting a cap board mount .......
142: Radio Road, RE: Ok (0.00)
Posted by mwiebe on 2009-03-12, 19:44:34 (75.173.1.226)
I couldn't agree with you more. My Dynaco FM3, Scott 350, Scott 350B all sound better, much better then the Sony--all on an APS-9B rooftop antenna. The Sony compresses the sound stage substantially in .......
143: Vinyl Asylum, Poo Bah Records 2636 E Colorado Blvd (0.00)
Posted by mwiebe on 2009-03-12, 10:32:33 (75.173.1.226)
I haven't been in Poo Bah's since it was in a small house 1101 East Walnut St. I don't know if they are in multiple locations now, but the selection of vinyl was always interesting and to my taste. Ma .......
144: Radio Road, Mike Zuccaro is here (0.00)
Posted by mwiebe on 2009-03-09, 18:23:41 (75.173.2.8)
Mike's website is here. He has been great servicing my Charlie Tuner as well. http://audiocraftsman.com/ 8795 Corvus place San Diego, Ca 92126-1920 Phone: 858-271-8294,email:mjzuccaro@aol.com Matt ::: .......
145: Tube DIY Asylum, RE: XSM15k/15k with nickel UPDATE (0.00)
Posted by mwiebe on 2009-03-02, 18:52:22 (75.173.2.8)
Dan, If the nickel core is run at full XSM15K/15K spec' then everything she says is true. Take the DC away and run it parallel feed I expect you will find it works just fine. How are you planing to us .......
146: Tubes Asylum, RE: EF86=EF40 (0.00)
Posted by mwiebe on 2009-02-18, 16:46:16 (75.161.89.32)
EF40s are electrically identical to EF86s, but they require an unusual base. Pin-out is different. If you have the correct base and can read this you can probably rewire a socket to make them work. Go .......
147: Tube DIY Asylum, RE: Nickel! Now we're cooking with gas! (0.00)
Posted by mwiebe on 2009-02-03, 06:35:01 (75.161.89.32)
Andy, You have to ask for nickel as it depends on what lams they have on hand. They will pretty much make you anything if they have the parts and price it reasonably. I have only used the WSM nickel a .......
148: Tube DIY Asylum, RE: Edcor interstages - update (0.00)
Posted by mwiebe on 2009-02-02, 20:17:20 (75.161.89.32)
Andy, I'm not sure what you are asking. If you are asking about the difference between XSM and WSM series, I've used both as interstages---single-end to single-end, single-end to P-P. I have not used .......
149: Tube DIY Asylum, RE: 6AK5/408A in triode (0.00)
Posted by mwiebe on 2009-01-19, 10:59:02 (75.161.89.205)
Look on the last page. http://frank.pocnet.net/sheets/138/5/5654.pdf .......
150: Tube DIY Asylum, PEC Water pipe (0.00)
Posted by mwiebe on 2008-12-13, 21:02:25 (75.161.95.15)
It's cheap and works great. Matt .......
151: Tube DIY Asylum, RE: Power transformer as a choke. (0.00)
Posted by mwiebe on 2008-12-05, 21:22:11 (75.161.67.68)
Dave, Thanks for that. I sometimes wonder if I could boost the L of a gapped output transformer used as a plate choke playing around with the secondary. Matt .......
152: Tube DIY Asylum, RE: Power transformer as a choke. (0.00)
Posted by mwiebe on 2008-12-04, 18:30:56 (75.161.67.68)
Dave, Any significant increase in L if you buck the secondary with the primary? Matt .......
153: Tube DIY Asylum, Hammond 166L2 (0.00)
Posted by mwiebe on 2008-12-03, 21:04:21 (75.161.67.68)
Iczerman, Like everyone is saying that's the wrong transformer. I expect things will work out better for you using one transformer per 2A3 (2.5V at 2.5A), so you need two transformers if you are using .......
154: MagneQuest/Peerless Forum, RE: T6 MagneQuest BCP-16Ni Grid Choke implementation question (0.00)
Posted by mwiebe on 2008-10-19, 20:29:12 (75.161.94.51)
Are you getting toggling voltage at the plate of the 300B in each amp or just one amp? Have you ever listened to music out of these amps which then developed this, or is this something you found on th .......
155: MagneQuest/Peerless Forum, RE: T6 MagneQuest BCP-16Ni Grid Choke implementation question (0.00)
Posted by mwiebe on 2008-10-19, 20:02:29 (75.161.94.51)
The most important thing is that you get the amp working correctly with the grid resistor back in the circuit. If you cannot stop it from oscillating adding the grid choke is just going to make troubl .......
156: MagneQuest/Peerless Forum, RE: EXO-35 terminal identification (0.00)
Posted by mwiebe on 2008-10-19, 19:42:57 (75.161.94.51)
Byron, If your meter used AC at about 30 hz to provide your resistance reading you would get closer 2.5K and 16 ohms. I expect your multimeter uses DC and there is not much resistance to DC through a .......
157: MagneQuest/Peerless Forum, RE: EXO-35 terminal identification (0.00)
Posted by mwiebe on 2008-10-19, 15:06:06 (75.161.94.51)
Byron, Convention is usually to have the writing on the primary side. However, it is also good practice to double check the transformer just to be safe, especially something as precious as cobalt. As .......
158: MagneQuest/Peerless Forum, RE: T6 MagneQuest BCP-16Ni Grid Choke implementation question (0.00)
Posted by mwiebe on 2008-10-18, 18:51:51 (75.161.94.51)
I know nothing about that particular amp, so my help is limited. If you hook the 220K resistor back up does it stop oscillating? Are you using a bypass resistor under the 300B cathode? The 1K grid res .......
159: MagneQuest/Peerless Forum, RE: Is the BH-7 Plate choke a catalog item? (0.00)
Posted by mwiebe on 2008-10-17, 07:25:34 (75.161.95.116)
Paul, Thanks for the additional info. I don't have any size constraints so it looks like the BAC-80 may be a good choice with the TFA-2004 for 300B like use. Though the Bottlehead packages are great v .......
160: MagneQuest/Peerless Forum, RE: Is the BH-7 Plate choke a catalog item? (0.00)
Posted by mwiebe on 2008-10-17, 07:20:05 (75.161.95.116)
Mike, The problem is the products link on the forum page goes to, http://www.magnequest.com/products.htm Which does not list all the Bottlehead iron. The link you suggested, www.magnequest.us, has it .......
161: MagneQuest/Peerless Forum, Is the BH-7 Plate choke a catalog item? (0.00)
Posted by mwiebe on 2008-10-16, 18:41:31 (75.161.95.116)
Mike, I see reference to the BH-7 choke as a production piece in the archives but I do not see it listed in your Bottlehead upgrade kits. Is this part available? If so what are its spec's and price? T .......
162: Tube DIY Asylum, Edcor EX-103 (0.00)
Posted by mwiebe on 2008-10-16, 11:03:42 (75.161.95.116)
Dan, Tell me about your autoformer volume control. I could not find an Edcor EX-103, do you have the spec’s for it? I’ve thought about using those multi-tap Edcors so I’m interested .......
163: Tube DIY Asylum, RE: recommendations for IDHTs (0.00)
Posted by mwiebe on 2008-10-16, 06:05:41 (75.161.95.116)
Thomas, A 6C41C works well below 400V, plate dissipation 25W, low Rp so transformer design is easy, and easy to drive and cheap. 6E6P or 6E5P trioded work as good cheap drivers. Matt .......
164: MagneQuest/Peerless Forum, RE: PING: Matt url for 12AX7 preamp (0.00)
Posted by mwiebe on 2008-09-16, 17:49:21 (75.161.95.116)
Triode3, I sure don’t know anything but I will comment nonetheless. As for philosophical questions, try this output impedance calculator, http://amps.zugster.net/tools/triode-calculator You can .......
165: Tube DIY Asylum, RE: DDDAC USB dac in passive I/V mode. (0.00)
Posted by mwiebe on 2008-09-16, 10:27:57 (75.161.95.116)
Wheezer, I bow to your efforts, most of my mods remain in the thought stage. What value are your Jupiter output caps? I've been wanting to put an iron based regulator supply on mine and get rid of m .......
166: Tube DIY Asylum, RE: Modified USB DAC board, DDDAC with triode buffer (0.00)
Posted by mwiebe on 2008-09-16, 08:29:21 (75.161.95.116)
wa2ise, I have always loved your submini tube work, and a big thanks for this. I've got the same DDDAC board and I have wanted an option to that big electrolytic, this will get me started. Matt ::: .......
167: MagneQuest/Peerless Forum, RE: PING: Matt url for 12AX7 preamp (0.00)
Posted by mwiebe on 2008-09-15, 19:30:22 (75.161.95.116)
Mike, Not only is the guy’s construction beautiful, his photography is just as good.That’s very hard stuff to shoot so my hat’s off to him. I liked his comment that the gain of the 1 .......
168: MagneQuest/Peerless Forum, RE: PING: Matt url for 12AX7 preamp (0.00)
Posted by mwiebe on 2008-09-15, 14:22:13 (75.161.95.116)
Mike, Thanks for the link, I will look it over. Matt .......
169: Tube DIY Asylum, 5676 to 1S5 (0.00)
Posted by mwiebe on 2008-09-15, 09:39:22 (75.161.95.116)
Michael, Sorry if the write up on the board suggested the 5676s were outputs, I was busy when he was writing all that stuff out and I wasn’t paying attention. It was actually a 5676 driving a 1S .......
170: Tube DIY Asylum, RE: 1st Tubed Project for Youngsters (0.00)
Posted by mwiebe on 2008-09-14, 21:47:43 (75.161.95.116)
Eli, Sounds interesting. My 7 year old built a 1S5 amp for a "science" fair, actually it was supposed to be a boom box run on bleach batteries, but we never could get the voltage or current we needed. .......
171: Tube DIY Asylum, 6BK5 6BD5 (0.00)
Posted by mwiebe on 2008-09-09, 08:55:55 (75.161.95.116)
Of course I have no idea what tube Douglas is so cagey about. But a cool feature of Duncan Amps Tube Data Sheet Locater (TDSL), a free download, is the ability to search for tubes by various parameter .......
172: SET Asylum, Wow, that's a beauty, thanks for posting (0.00)
Posted by mwiebe on 2008-08-08, 10:26:13 (75.161.72.80)
.......
173: MagneQuest/Peerless Forum, RE: HabLabs PA10 (0.00)
Posted by mwiebe on 2008-05-28, 16:47:58 (75.161.75.1)
Jamie, I'm not sure what your question is. I have used the 6E5P, 6E6P quite a bit and they work fine with the EXO-173 phase splitting choke and pretty much any of Mike's plate chokes that are 60H or b .......
174: MagneQuest/Peerless Forum, these are my hole fillers in the line (0.00)
Posted by mwiebe on 2008-05-21, 08:13:52 (75.161.75.1)
Mike, I know you have discontinued many of the parts I listed above, its just nice to see all that you have done over the past years. And you know I could list more. Do you want to note your core op .......
175: MagneQuest/Peerless Forum, I don't see these products listed (0.00)
Posted by mwiebe on 2008-05-21, 07:57:43 (75.161.75.1)
Mike, You might also want to list all your Bottlehead update iron as production units? I do not see these plate chokes listed: BCP-16 (400H/1ma), is the EXO-002 the same as EXO-001? The first is the .......
176: Tubes Asylum, RE: More thoriated tungsten nighttime goodness... (0.00)
Posted by mwiebe on 2008-04-18, 09:29:57 (75.161.85.15)
Jim, Nice. I'm doing something similar with SV811-10 and 6FD7, kind of a 6EA7 in a bloated 9-pin bottle. I'm setting the 6FD7 power triode over a choke and running my SV811 A2. I really like the SV811 .......
177: Tube DIY Asylum, My bad (0.00)
Posted by mwiebe on 2008-04-10, 19:12:22 (75.173.1.251)
Those pin outs for the 6N33B are correct, my problem I assumed the cut lead marked #1 like it does on the 6N28B which I was just working with. The cut lead on the 6N33B is #7 and then it all falls int .......
178: Tube DIY Asylum, RE: 6N33B 6H33 Russian subminature pin out? (0.00)
Posted by mwiebe on 2008-04-09, 20:35:38 (75.173.1.251)
Unfortunatly that pin-out is not for the 6N33B, but thanks anyway. If I get time in a few days I will figure it out myself. Matt .......
179: Tube DIY Asylum, 6N33B 6H33 Russian subminature pin out? (0.00)
Posted by mwiebe on 2008-04-09, 08:23:33 (75.173.1.251)
The pin out of this Russian subminature tube with flying leads on the net are incorrect. This tube has nine flying leads and pins 3 and 8 appear to be the filament. Can any one help out? Thanks, Matt .......
180: MagneQuest/Peerless Forum, RE: Tungar (0.00)
Posted by mwiebe on 2008-03-24, 09:48:09 (75.161.84.214)
You also hear a lot of stuff about how noisy mercury rectifiers are. I haven’t tried tungars yet but I intend to for filament/field coil supplies. The old Motiograph, RCA and WE tungar field coi .......
181: MagneQuest/Peerless Forum, Tungar (0.00)
Posted by mwiebe on 2008-03-23, 07:17:08 (75.161.84.214)
Steve, These tubes were used to recharge batteries, power field coil speakers and other low-volts high amps needs. Many come with threaded mount like a light bulb. Matt .......
182: Tube DIY Asylum, RE: Quick Q about IT's (0.00)
Posted by mwiebe on 2008-03-16, 06:20:23 (75.161.84.214)
They work great as phase splitters or interstage transformers. Though normally I use the WSM 10K/10K to split phase at the input and direct couple after that. They will need to be used in parallel fee .......
183: Tube DIY Asylum, RE: Anyone have a Dyna MK III chassis? (0.00)
Posted by mwiebe on 2008-03-11, 20:32:08 (75.161.84.214)
Jeff, I'm sure you know but you can buy new MkIII chassis $90, http://www.dynakitparts.com/store/product.aspx?id=197 Matt .......
184: MagneQuest/Peerless Forum, RE: More EIMACs, more parafeed, more fun (0.00)
Posted by mwiebe on 2008-03-11, 07:56:48 (75.161.84.214)
Gianluca, Thanks for that. You've got more iron in that little box then I thought. No wonder its on wheels. Matt .......
185: MagneQuest/Peerless Forum, RE: More EIMACs, more parafeed, more fun (0.00)
Posted by mwiebe on 2008-03-11, 05:53:53 (75.161.84.214)
Gianluca, Nice and simple. How are you heating your 801A filaments? I kind of got lost in the archive if you have explained that before. Given all that iron it doesn't look like you have an iron solut .......
186: SET Asylum, RE: Cathode follower or power tube as 211 driver (0.00)
Posted by mwiebe on 2008-03-10, 18:55:35 (75.161.84.214)
As Douglas mentions, you cannot use a cap to couple as it blocks DC. Cap coupling’s DC impedance is really high by design, consequently it cannot provide any grid current. All grid current is bl .......
187: Tube DIY Asylum, Power Transformer Resistance readings (0.00)
Posted by mwiebe on 2008-03-09, 19:45:37 (75.161.84.214)
Dan, I just noticed I had these power transformer readings of the replacement transformer VTL sold me. I'm assuming the transformer lugs are numbered, but I have no idea if these numbers correspond to .......
188: Tube DIY Asylum, RE: Bias and bad Power Transformer (0.00)
Posted by mwiebe on 2008-03-09, 18:37:09 (75.161.84.214)
Dan, You should not have any continuity between the filament windings and the B+ High voltage winding. And the resistance readings of the filament windings will be less then the high-voltage winding b .......
189: Tube DIY Asylum, Bias and bad Power Transformer (0.00)
Posted by mwiebe on 2008-03-09, 15:51:25 (75.161.84.214)
Dan, When you pull the bottom off the amp you will see four adjustable plastic pots, and four test points, adjust the pots so you are 0.180V across the test point to ground for each of the four el84s. .......
190: Tube DIY Asylum, RE: Troubleshooting a VTL TT-25 (0.00)
Posted by mwiebe on 2008-03-09, 09:18:39 (75.161.84.214)
Dan, That is my readings of two amps, unit#1 and unit#2, the readings on the EL84s is the same so a reading for one applies to all four. Matt .......
191: Tube DIY Asylum, RE: Troubleshooting a VTL TT-25 (0.00)
Posted by mwiebe on 2008-03-09, 05:52:31 (75.161.84.214)
Dan, As Michael said, swap tubes around and see what happens. I have a set of those amps and they are a bit hard on tubes, they run them hot. You will have to pull the red anno cover off to adjust bi .......
192: MagneQuest/Peerless Forum, RE: vacuum tube archeologist..... (0.00)
Posted by mwiebe on 2008-03-05, 14:09:59 (75.161.84.214)
Mike, I don’t think the 26 or thoriated filament tubes are quaking in their boots. I’m just looking for filament frugal tubes that sound good. I still use battery filaments/B+ so longer .......
193: MagneQuest/Peerless Forum, RE: Bas are you using your B7 yet? (0.00)
Posted by mwiebe on 2008-03-05, 09:56:51 (75.161.84.214)
Dyna Saur, Thanks for the data page. I remain impressed with the sound of the 1J17B for what it is, but not so with the 1J24B. I still have to socket 1J18B 1Ж18Б, 1J24B 1Ж24Б, .......
194: MagneQuest/Peerless Forum, RE: Not using the B7's yet unfortunately...but it is the next project (0.00)
Posted by mwiebe on 2008-03-05, 06:57:59 (75.161.84.214)
Bas, A 4-pin socket, or octal, with wires ending in alligator clips makes swapping between acorns and sub-miniatures easy. I’ve linked an Ebay 1J17B auction below. “Urals” seems to o .......
195: MagneQuest/Peerless Forum, Bas are you using your B7 yet? (0.00)
Posted by mwiebe on 2008-03-04, 09:45:44 (75.161.84.214)
Bas, I don’t know if you have your B7 in use but if not here is an easy suggestion to try. I’m always on the lookout for cheap--filament frugal because I use batteries--directly heated .......
196: Tube DIY Asylum, SV572, 6.3V/4a 125W (nt) (0.00)
Posted by mwiebe on 2008-02-17, 09:24:58 (75.161.83.35)
.......
197: MagneQuest/Peerless Forum, RE: Needs more iron (0.00)
Posted by mwiebe on 2008-02-10, 19:11:57 (75.161.83.35)
Mike, No wonder that input trans threw me for a loop, but I see your idea now, a P-P platform—something like the Seth iron package for pentodes, with similar upgrade path. I wonder if fixed bia .......
198: MagneQuest/Peerless Forum, Needs more iron (0.00)
Posted by mwiebe on 2008-02-10, 09:49:27 (75.161.83.35)
Mike, All those CCSs when you make such nice iron seems bad for business. I would like to hear more about the input phase splitter, which is complicated with the volume control and one end grounded r .......
199: Tubes Asylum, RE: Is Ned gone from Triode Electronics? (0.00)
Posted by mwiebe on 2008-02-06, 20:50:20 (75.161.83.35)
Ned is here, www.tubezone.net Matt .......
200: SET Asylum, RE: Useless Fi Primer Hum POT? (0.00)
Posted by mwiebe on 2008-02-03, 17:13:03 (75.161.83.35)
AC on indirectly heated tubes depends on their Mu, the circuit and some other things. Mostly you can get away with it. If you suspect AC hum on your driver, bias the heater 10 to 20V over the cathode .......
201: SET Asylum, RE: Useless Fi Primer Hum POT? (0.00)
Posted by mwiebe on 2008-02-03, 12:19:41 (75.173.1.241)
I’ve used Tent supplies, current/voltage supplies, bench supplies, batteries and LCLCs--in comparison AC sounds just fine sometimes. It becomes a balance between hum tolerance, which is speaker .......
202: SET Asylum, RE: Useless Fi Primer Hum POT? (0.00)
Posted by mwiebe on 2008-02-03, 12:17:32 (75.173.1.241)
I think your ears told you whether you needed the pots for your linear supply. Sometimes it is that simple. Matt .......
203: SET Asylum, RE: Useless Fi Primer Hum POT? (0.00)
Posted by mwiebe on 2008-02-03, 12:02:21 (75.173.1.241)
You are right, there is quite a bit of AC on the schematic filament design and the hum pot would be needed. I was commenting on the original posters use of a linear bench supply for filament heating f .......
204: SET Asylum, RE: Useless Fi Primer Hum POT? (0.00)
Posted by mwiebe on 2008-02-03, 07:14:54 (75.173.1.241)
As you've noticed hum pots serve no purpose with DC filament supplies. However they make a big difference for AC heating. With DC one filament is positive, one negitive, so think about what might be g .......
205: Tube DIY Asylum, KOA SPR2 from Mouser the same (0.00)
Posted by mwiebe on 2008-02-01, 17:12:35 (75.173.1.241)
The SPR2 look identical to Kiwame at about $0.30 each, but limited selection of 1W and 2W. Only one value of 5W SPR at Mouser.FWIW. Matt .......
206: Tube DIY Asylum, Thanks (0.00)
Posted by mwiebe on 2008-01-27, 11:26:32 (75.161.68.28)
The historical context makes sense for consumer battery radios, but one would think there are still a few military tubes. I think there are a few more sub-minis I haven’t found yet. Thanks for t .......
207: Tube DIY Asylum, What are some small directly heated Russian tubes? (0.00)
Posted by mwiebe on 2008-01-26, 17:09:12 (75.161.68.28)
I’m looking for some Russian directly heated tubes--triode, tetrode or pentode--to play with that are not made to Western spec’s like 2A3, 300B, 6B4G (6C4C), or the big ones like the GM10 .......
208: Vinyl Asylum, Making alternative ESL headshell (0.00)
Posted by mwiebe on 2008-01-17, 11:17:03 (75.161.85.218)
I don’t know if this has been covered before but I’ve wanted an alternative headshell for my ESL arm with a diamond configured pin-out--rotated 45-degrees from normal. I purchased a Sumiko .......
209: Tube DIY Asylum, Push-pull Class A is not immune to PS (0.00)
Posted by mwiebe on 2008-01-15, 15:20:57 (75.161.85.218)
Class A P-P being immune to PS variations makes sense, but it is not what I have experienced. Given the way I build, easily swappable signal and power supply combinations, I can swap between tube regu .......
210: Tubes Asylum, RE: So how does it sound? (nt) (0.00)
Posted by mwiebe on 2008-01-10, 08:47:07 (75.161.85.218)
It sounds fine. Better high-end then a 6C45 spud but less bass and a lot like a 8233 spud. But then that was all different iron and speakers so what’s it all mean? 6E5P/6E6P are cheap so what is .......
211: Tubes Asylum, How about a 6E5P Spud? (0.00)
Posted by mwiebe on 2008-01-09, 10:33:13 (75.161.85.218)
There is also the similar 6E6P. I've just used them as cathode A2 drive to a 6HS8, for which they worked fine. Matt .......
212: Tube DIY Asylum, RE: power amp input transformers Q . (0.00)
Posted by mwiebe on 2008-01-03, 20:54:50 (75.161.79.164)
I’m surprised with the EF37 you are looking for gain, nevertheless with center taps you have quite a few options to play around with. At the end of the day stepping down the preamp only to step .......
213: Tube DIY Asylum, RE: power amp input transformers Q . (0.00)
Posted by mwiebe on 2008-01-03, 19:28:21 (75.161.79.164)
Is the 20K side center tapped at all? Running them input into 20K/output 600 ohms is quite a bit of step down, twice since you are stepping down your preamp as well. If you have lots of gain to burn g .......
214: Tube DIY Asylum, RE: The 5676 - no Lifetime Achievement Award! (0.00)
Posted by mwiebe on 2007-11-26, 15:17:58 (75.161.84.37)
I don't know what to say. I've read about longevity issues with this tube, but in my experience using about a dozen over 10 years, they are not noticeably short lived. My only guess is your filament s .......
215: Tube DIY Asylum, RE: The 5676 - no Lifetime Achievement Award! (0.00)
Posted by mwiebe on 2007-11-26, 11:43:58 (75.161.84.37)
Andy, I’ve not had issues with 5676 short life, seems like a few pairs have well over 600 hours on them. Mine are Raytheon branded with red lettering if that means anything. Many small battery .......
216: Tube DIY Asylum, 6H30Pi Octal (0.00)
Posted by mwiebe on 2007-11-19, 05:38:15 (75.161.73.92)
To keep it octal this is one possibility. Same specs as the 6H30 9-pin but with chunky octal ceramic base. Lower mu (15 vs. 22), lower rp, higher conductance compared to ECC99. Both great tubes that w .......
217: High Efficiency Speaker Asylum, RE: Field coil question.. (0.00)
Posted by mwiebe on 2007-11-17, 15:46:19 (75.161.72.136)
I think a lab supply is best. Just ramp up your voltage slowly and feel the motor so it doesn't get too hot. There is plenty on this in the archives. Open baffle use may require less voltage then othe .......
218: Tube DIY Asylum, I second nothing (0.00)
Posted by mwiebe on 2007-11-17, 14:18:11 (75.161.72.136)
As pointed out Amity does it. K&K’s schematic encourages it, http://www.kandkaudio.com/images/PPAmpInput.pdf I use Edcor’s $10 WSM10K/10K, Altec 15355s with paired resistor center tap on t .......
219: Tube DIY Asylum, RE: Looking for low to moderately complex 100% DHT schematic (0.00)
Posted by mwiebe on 2007-11-17, 11:22:06 (75.161.72.136)
So you want to get away of the CCS on top of the T20. I'm going to try a Magnequest EXO-099 (serial 10ma 750H 2,200 ohms DCR) over the 35T first as I've read folks use them nicely over 3C24s, 15E. I'm .......
220: Tube DIY Asylum, RE: Looking for low to moderately complex 100% DHT schematic (0.00)
Posted by mwiebe on 2007-11-17, 10:13:44 (75.161.72.136)
Sweet project. I'm headed that direction with 35T A2 to 211. Why are you pulling the T20s? They sure look nice. I love the bass from those James as well. Matt .......
221: Tube DIY Asylum, RE: Re: efficiency (0.00)
Posted by mwiebe on 2007-11-16, 18:37:46 (75.161.72.136)
Adam Rated adequately, do you mean for a 2A3 running 65ma or so? Magnequest EXO-030, BAC-80, SPJC-60 Electra Print AC6031 gapped for 65ma www.vt4c.com 050-80H65, I know he rates this for less current .......
222: Tube DIY Asylum, RE: Looking for low to moderately complex 100% DHT schematic (0.00)
Posted by mwiebe on 2007-11-16, 12:35:11 (75.161.79.147)
Adam, Your low speaker sensitivity is working against you. Assuming you meant 6SN7 driven 2A3, given your speaker sensitivity that would be a rare fit, unless you listen to music quietly and in a smal .......
223: MagneQuest/Peerless Forum, RE: Hi Matt, here is the post by Paul (0.00)
Posted by mwiebe on 2007-11-14, 08:38:53 (75.161.88.27)
Bas, I can’t speak for Paul. I do not follow what is being suggested. Signal ground and chassis ground are entirely different things, though it is suggested to hook chassis and signal together a .......
224: MagneQuest/Peerless Forum, RE: Why should the B7 be connected to ground (via centertap) (0.00)
Posted by mwiebe on 2007-11-14, 07:00:42 (75.161.88.27)
Bas, I don’t know to what schematic you are referring to, but connecting the secondary center-tap to ground is a good way to make a phase splitter or balanced drive. While I haven’t hook .......
225: Tube DIY Asylum, RE: How important is low DCR for class A PP? (0.00)
Posted by mwiebe on 2007-11-06, 16:03:12 (75.161.73.37)
As a heuristic Jeff’s suggestion that the voice coils boogie better with low DCR is suggestive for what I hear. The music is more liquid and musical in the same way an A2 amp sounds different fr .......
226: Tube DIY Asylum, RE: How important is low DCR for class A PP? (0.00)
Posted by mwiebe on 2007-11-05, 11:51:41 (75.173.2.102)
I was also curious so I plugged my low-DCR supply--Signal Transformer DU-1/2, Cree full-bridge, Hammond 159ZC, 50uF, Triad C-47U, 50uF, Triad C-40X, 50uF--onto a 6V6 P-P amp a while ago. This supply r .......
227: Tube DIY Asylum, RE: Sound Practices 13 (0.00)
Posted by mwiebe on 2007-10-31, 14:35:32 (75.173.0.44)
They are pretty easy to come by on Ebay so that may be your best bet, seller n5kat. This topic comes up frequently here so if you search you may find other ways of getting back issues. Matt ::: TOPIC: .......
228: Tube DIY Asylum, RE: RCA Amps--Information Appreciated (0.00)
Posted by mwiebe on 2007-10-24, 13:55:01 (75.161.84.178)
You may look on the RCA archive link at Oswald Mill Audio site. I didn't see your model name listed but it may be there under a different name. You could also ask on their forum I expect. Good luck, s .......
229: Tube DIY Asylum, RE: Edcor Interstages - 10k and 15k (0.00)
Posted by mwiebe on 2007-10-20, 16:33:52 (75.161.84.178)
The 15K versions are relatively recent, past 6 months or so, whereas the 10K versions have been available for years. That probably is why there are more comments on the 10K and few on the 15K. In my .......
230: MagneQuest/Peerless Forum, Re: parafeed push-pull schematics (0.00)
Posted by mwiebe on 2007-02-20, 18:18:28 (71.213.176.90)
Steve, If you just want a generic description of some parallel feed P-P topologies this might help, http://www.nutshellhifi.com/library/ETF.html Scroll down towards the bottom for P-P circuits. Matt : .......
231: SET Asylum, Re: 26 instead of 27 driver w/45 (0.00)
Posted by mwiebe on 2007-01-29, 13:41:30 (71.213.176.90)
Quite a lot. Changing from a 5-pin socket to a 6-pin will be the easiest change. While the mu of the tubes is similar the 26 may require you to drop the B+ a bit. The real issue is going to be figurin .......
232: MagneQuest/Peerless Forum, Re: BCP-16 DC current (0.00)
Posted by mwiebe on 2007-01-15, 12:10:31 (71.213.176.90)
Its size factor and low drop have me thinking about low-voltage battery stuff with a 6088, 6GM8, 1LE3, 5798 or 6CG7 for which its load is too high but should work. Matt .......
233: MagneQuest/Peerless Forum, Re: BCP-16 DC current (0.00)
Posted by mwiebe on 2007-01-13, 15:46:34 (71.213.176.90)
Mike, Thanks for the response, I would be interested in a pair of these small plate chokes next time you have a production run going. Sounds like something fun to play with. Matt .......
234: MagneQuest/Peerless Forum, BCP-16 DC current (0.00)
Posted by mwiebe on 2007-01-13, 13:20:56 (71.213.176.90)
I know these were a Freed design for plate loading a 12AX7 mic preamp. What is the DC limit of these plate/grid chokes? Both the M6 and Nickel versions? Thanks for any info. Matt .......
235: MagneQuest/Peerless Forum, Re: OT: if your from Santa Fe... you'll enjoy this photo (0.00)
Posted by mwiebe on 2007-01-08, 18:53:17 (71.213.176.90)
Mike, Note how the fork is turned around so the rider can get closer to the Derny, though this looks like its heading for faster then Derny speed. I haven't got around to the TA call yet, too busy. .......
236: Tubes Asylum, Re: JAN-832A Tubes (0.00)
Posted by mwiebe on 2006-11-02, 15:52:39 (71.213.162.209)
I'm not sure using a 832A would be my first project but have at it. Here is a link to a 829A amp which is a slightly larger 832A. http://www.pmillett.com/829b_amplifier.htm I’ve only used the 83 .......
237: High Efficiency Speaker Asylum, Re: Jensen A12 A-12 field coil drivers (0.00)
Posted by mwiebe on 2006-10-28, 15:54:56 (71.213.162.209)
Andy, I would be wary, vary wary, of just applying 100V to any field coil. Some field-coils are designed for 12Vs and you can imagine what 100V would do to them. If the power rating of the field-coi .......
238: MagneQuest/Peerless Forum, Isn't the EXO-030 spec' closer to 50H (0.00)
Posted by mwiebe on 2006-10-22, 10:56:13 (71.213.162.209)
Maybe it's part of Magnaquest urban legend but I thought the 30H rating on the EXO-030 was a mistake never corrected. I thought this choke was closer to 50H. Matt .......
239: Tube DIY Asylum, Re: 6V6 PP with Interstage Transformer? (0.00)
Posted by mwiebe on 2006-10-21, 07:46:01 (71.213.162.209)
Here's something to get you started. B+ is low for some reason I forgot since I was using parts at hand. Sounded nice for something so simple. Driver tube could be anything with mu of 35 up. Matt ::: .......
240: MagneQuest/Peerless Forum, Re: EXO-01 (0.00)
Posted by mwiebe on 2006-04-20, 05:59:20 (168.103.112.225)
The 717A in the Yamamoto is hooked up as a pentode. So it may not be the best thing for the plate, but I guess you could use it on the screen. But I expect you would get better bang for your buck usin .......
241: MagneQuest/Peerless Forum, My Mom still loves me (0.00)
Posted by mwiebe on 2006-03-26, 19:14:24 (168.103.112.225)
Mike, I was just having fun, I figure you would gladly sell to whoever ponies up the money. And you haven't shammed me into top shelf construction techniques because alligator clips have never let m .......
242: MagneQuest/Peerless Forum, Forbidden fruit (0.00)
Posted by mwiebe on 2006-03-26, 17:38:49 (168.103.112.225)
Mike, "reserve them for top shelf projects and OEM's."--Wow that hurt, it must of been some of my clip-lead project photos. Well I better keep my eye pealed for a few more falling off the worktable an .......
243: MagneQuest/Peerless Forum, When will Extra Linear Chokes Be Offered? (0.00)
Posted by mwiebe on 2006-03-26, 15:17:11 (168.103.112.225)
Mike, I know the 845/211 plate choke is an Extra Linear design, and it sounds like the BCP-15s you just wound for Bottlehead were Extra Linear. Is this now an option on all your plate chokes going for .......
244: MagneQuest/Peerless Forum, Re: Mike! What would be the Henry for (0.00)
Posted by mwiebe on 2006-03-08, 20:04:16 (67.41.99.87)
Tanker, Mike ran some RIT sims for me. I hope Mike corrects me if I'm wrong but there is little change from 20ma to 30ma, both about 30H. I didn't have him run any lower current sims. Matt ::: TOPIC:: .......
245: Tube DIY Asylum, Re: 316Apushpull (0.00)
Posted by mwiebe on 2006-03-08, 08:19:09 (67.41.99.87)
Fred, The lower DCR of the choke may allow the designer to get a direct cathode connection to the grid of the 417A at the operating points chosen without recourse to a negative supply under the 717A c .......
246: MagneQuest/Peerless Forum, Re: Ingot eye candy III (0.00)
Posted by mwiebe on 2006-03-07, 07:09:20 (67.41.99.87)
Clever feet idea if I'm seeing what I think I am. I may borrow the idea using Nosler Ballistic Tips for a non-maring approach. Matt .......
247: MagneQuest/Peerless Forum, 6HS5 in A2 (0.00)
Posted by mwiebe on 2006-02-20, 10:56:47 (67.41.99.87)
I still need to play with this a bit. Using the SJPC I hoped to pull it off without recourse to a negitive supply but I'm going to probably drop the bottom of the choke by 2V or so to get more current .......
248: MagneQuest/Peerless Forum, What's order deadline? (0.00)
Posted by mwiebe on 2006-01-30, 12:40:35 (168.103.102.14)
Mike, I know voltage spec' for parafeed is somewhat irrelevant compared with series but I was wondering about the freedom to move the blocking cap around. What “high-voltage” means to yo .......
249: MagneQuest/Peerless Forum, Re: got it: FS-100PF for 211/845 apps (0.00)
Posted by mwiebe on 2006-01-30, 09:28:54 (168.103.102.14)
Mike, Such good news, I'm in too but would like a bit more clarification. What is the recommended voltage of the Kraft paper version? What is the recommended voltage of the Nomex? Is the "Super" opt .......
250: MagneQuest/Peerless Forum, Re: hooking up 15335 for phase splitting duty (0.00)
Posted by mwiebe on 2005-07-26, 18:56:22 (65.102.100.51)
Mike, Thanks, not what I was expecting but I understand. Hopefully I will get to try it this weekend or next. Nice to use those things other than as interstages. Matt .......
251: MagneQuest/Peerless Forum, You've got my attention--15335 input-phase splitter (0.00)
Posted by mwiebe on 2005-07-26, 15:03:55 (65.102.100.51)
Mike, Here I was looking for a small phase splitter for a 6EM7 P-P amp and your email hits. I got a pair of 15335's but never considered them. Since I have two voltage amps with the 6EM7s I may use .......
252: MagneQuest/Peerless Forum, No worrys Mike, I'm away from home for a few weeks (nt) (0.00)
Posted by mwiebe on 2005-02-27, 19:40:08 (71.33.56.138)
nt .......
253: MagneQuest/Peerless Forum, Re: I wish I had a prize for you (0.00)
Posted by mwiebe on 2005-02-26, 19:13:02 (71.33.56.138)
Dugast feels about his tires what you feel about your iron, enough said. As to reward if I get those SJPC 60ma/100H chokes I have on order before I'm out of tights, that's prize enough. Fixed is the p .......
254: MagneQuest/Peerless Forum, OT: Not going to touch that, A Dugast Paris/Roubaix Silks (0.00)
Posted by mwiebe on 2005-02-25, 09:52:10 (71.33.56.138)
OT .......
255: MagneQuest/Peerless Forum, Re: ignition coil output autoformer (0.00)
Posted by mwiebe on 2005-02-24, 17:24:04 (71.33.56.138)
So how much power supply ripple reduction does a 225/16 steel belted radial have? Thanks for the link, kind of wakes one up to thinking again. Matt .......
256: Tubes Asylum, Re: EF40 socket? (0.00)
Posted by mwiebe on 2004-03-03, 11:18:16 (63.230.99.196)
Kevin, I bought a few from AES last year sometime. Give them a call and ask, they may still have a few. Matt .......
257: Tube DIY Asylum, Ultrasonic (0.00)
Posted by mwiebe on 2004-02-03, 20:11:03 (63.230.99.196)
So far I haven't had hum bother me so I haven't tried Bench's suggestions. Guess I need more efficient speakers. Your reports have got me looking at ultrasonic as well, especially the little lighting .......
258: Tube DIY Asylum, Not quite what you suggest but close using DHT (0.00)
Posted by mwiebe on 2004-02-03, 14:03:55 (63.230.99.196)
This approach feeds it back via the filament but its close. Matt .......
259: Bottlehead Forum, Sorry, Different Mike W <nt> (0.00)
Posted by mwiebe on 2004-02-01, 16:02:00 (63.230.99.196)
.......
260: Bottlehead Forum, Re: 45s in Paramour (0.00)
Posted by mwiebe on 2004-02-01, 10:41:15 (63.230.99.196)
Mike, I just took the line voltage down to get about Vp-c 280V on the 45, Ip was ballpark 35-37ma or something like that with the Paramour's stock bias resistor/bypass. Heater voltages for the 45 an .......
261: Bottlehead Forum, 45s in Paramour (0.00)
Posted by mwiebe on 2004-02-01, 07:17:04 (63.230.99.196)
A while back I put my Paramours on a Variac so I could drop in some 45s in place of the 2A3s. This turned out to be an improvement in sound for me. I was A/Bing between Sovtec and Valve Arts, since it .......
262: Tube DIY Asylum, How about DHP phono? (0.00)
Posted by mwiebe on 2003-02-22, 06:58:40 (67.41.98.235)
I know you asked for a DHT how about a direct heated pentode? Steve Bench’s battery DHP phono pre at, http://members.aol.com/sbench/6088pre2.html I’ve been using it for about two years now and it soun .......
263: Tubes Asylum, Re: Dynaco Mark III tweaks (0.00)
Posted by mwiebe on 2003-01-29, 16:01:17 (63.230.96.123)
I'ld agree with T-Tiger. I have played with my MK-III for years finally doing the whole Curcio thing to one pair, though circa '81. I recently decided to rebuild another stock pair with a stock board .......
264: Bottlehead Forum, Re: Foreplay with B7 OPT vs. Soul Sister (0.00)
Posted by mwiebe on 2003-01-13, 11:28:04 (63.230.97.246)
You may want to have a look at how VoltSecond plumbed his Sowter transformers into his Foreplay. http://www.siteswithstyle.com/VoltSecond/Foreplay_headphone/Foreplay_to_Headphones.html The only way yo .......
265: Bottlehead Forum, Re: Anyone ever try battery biasing their driver tubes? (0.00)
Posted by mwiebe on 2003-01-09, 16:59:30 (63.230.97.246)
Mike, It is certainly very easy to do for the 12AT7 driver. You will need to measure your current grid bias, pin 7 to pin 8 to keep as a reference. Than it looks like two 1.1V nicads will get you clo .......
266: Bottlehead Forum, Re: OT: Good place to get enclosures other than Hammond? (0.00)
Posted by mwiebe on 2003-01-06, 17:34:07 (63.230.97.246)
Enclosures are hard to come by if you cannot find someone local with a break to do some metal work for you. If your wood skills are okay, you can use copper clad circuit boards (Radio Shack, Mouser, D .......
267: Tube DIY Asylum, Re: help with parafeed IT transformer setup... (0.00)
Posted by mwiebe on 2003-01-01, 19:39:15 (63.230.97.246)
Check that your grid bias--Ia--for the 6BQ5s is the same with the Edcors as it was with the 6N1P phase splitter. You may have pushed opperating points about more than you think. Kind of sounds like yo .......
268: Welborne Labs, Are you paralleling 6GM8 sections? (0.00)
Posted by mwiebe on 2002-12-30, 10:45:31 (63.230.97.246)
Nice preamp! Are you using one triode section a channel--to switch tubes on aging--or are you paralleling sections? I'm just curious since battery life would be greatly extended with only one tube. By .......
269: Tube DIY Asylum, Re: supposedly i need a lot more than just the batteries for power (0.00)
Posted by mwiebe on 2002-12-29, 10:30:40 (63.230.97.246)
There are plenty of tubes you can get by using a few 9V batteries for B+. The ECC86/6GM8 7N7 recommended is quite nice and sounds good on as little as 18Vs. Its 6.3V heater should be easy to supply. A .......
270: Bottlehead Forum, Re: Need Resister question answered or no chance of Paramour birth tonight (0.00)
Posted by mwiebe on 2002-12-23, 07:01:15 (63.230.97.246)
280K metal film would be fine, and you can probably get up to 30% off on that part and not hear much difference if driven by most tube gear. It loads the output of what ever is up stream. Taking a CD .......
271: Tubes Asylum, Re: bias adjustment kits - do they do the job? (0.00)
Posted by mwiebe on 2002-12-10, 15:23:13 (67.41.98.15)
This is not what you need. I had a 299C a while ago and I don't think it has bias adjustment but I don't have a schematic at hand to look. You may want to ask this question on the www.hhscott.com foru .......
272: Tube DIY Asylum, Re: hold your horse..too many tips! (0.00)
Posted by mwiebe on 2002-12-02, 20:50:54 (63.230.96.235)
With the Magnaquest line transformer (B7?) you will need a parallel feed (Soul Sister) so that settles some of your circuit. Don't worry about a fancy current source use a 18K wirewound resister, list .......
273: Tube DIY Asylum, Re: 5676 life time..only 100 hours? (0.00)
Posted by mwiebe on 2002-12-02, 19:17:27 (63.230.96.235)
Have fun. I don't think you will find tube life an issue if you keep them vertical and filament around spec. The filaments must flop around a bit if you give them too many volts. I have run B+ as low .......
274: Tube DIY Asylum, Re: 5676 life time..only 100 hours? (0.00)
Posted by mwiebe on 2002-12-02, 18:09:17 (63.230.96.235)
Sorry, I didn't mean to alarm you. Antique Electric Supply had 5676s on sale last year for $0.50 and at that price I did some things to DHTs I wouldn't normally. I tortured them a bit hard with taking .......
275: Tube DIY Asylum, Re: Has somebody tried 5676 ? (0.00)
Posted by mwiebe on 2002-12-02, 16:07:14 (63.230.96.235)
I have made a few line stages from them, RC and transformer coupled, and they sound quite nice. Also use them as drivers for 5902s, and 6397 sub-mini power tubes. If you search the net you will find a .......
276: Tube DIY Asylum, Re: anyone try this battery powered phono? (0.00)
Posted by mwiebe on 2002-11-08, 05:25:13 (63.230.96.235)
Eric, I'm not so good on the sonic flavor description. I use a Dynavector 10X4 MkII and the gain through an ElectraPrint Ultrapath preamp is all I ask for. It has great imaging and a relaxed sound a .......
277: Tube DIY Asylum, Re: anyone try this battery powered phono? (0.00)
Posted by mwiebe on 2002-11-06, 17:07:46 (63.230.96.235)
Chiggy, I cannot comment on that particular one. But I built Steve Bench's battery powered 6088 (http://members.aol.com/sbench/6088pre2.html)last year and love it. You have to watch fillament voltage .......
278: Tube DIY Asylum, Re: SRPP with IT ? (0.00)
Posted by mwiebe on 2002-11-04, 14:03:12 (63.230.96.235)
Why not SRPP with IT? Can someone point me to something to read on this, either how to plumb the IT into the topology or why it wont work no matter what? I admit I have tried it without good results. .......
279: Bottlehead Forum, Re: Choke mounting (0.00)
Posted by mwiebe on 2002-10-28, 08:40:07 (63.230.96.235)
Surplus Sales has small Triad 10H/90ma chokes (270 DCR) for sale ($22) that are not much bigger than the 155H, though twice the cost. Matt .......
280: Bottlehead Forum, Choke mounting (0.00)
Posted by mwiebe on 2002-10-27, 16:58:44 (63.230.96.235)
John, I used a Hammond 193B since I had a pair. I screwed them into the wood base centered under the power switch, laminations vertical. I kept the leads long and hanging in air so I could pop the top .......
281: Bottlehead Forum, Paramour’s iron enrichment diet (0.00)
Posted by mwiebe on 2002-10-27, 16:02:18 (63.230.96.235)
Got my Paramours together and haven’t added the CS4 yet. I wanted to get used the sound so I could better hear the CS4 addition. Well the 23mV hum, even for my 83dB LS3/5As, was too much. I added a .......
282: Bottlehead Forum, Re: 6021 preamp w/ c4s [pic] (0.00)
Posted by mwiebe on 2002-09-05, 19:07:11 (63.230.97.136)
Berlin, Those 6021s are impressive, especially nice at the 50 cent price AES sells them for on occasion. And they don’t ring no matter what. I haven’t really played much with operating points, using .......
283: Tubes Asylum, Re: Battery bias (0.00)
Posted by mwiebe on 2002-08-21, 12:59:06 (63.230.97.136)
I have used batteries for cathode bias on small power tubes (5902 P-P) but I would think size of cathode current for larger tubes would demand pretty big batteries. For larger tubes pushing the grid a .......
284: Tubes Asylum, Re: Just ordered some. Who needs them? (0.00)
Posted by mwiebe on 2002-08-20, 05:29:13 (63.230.97.136)
Dan, I will buy four if you are able to change your order. Thanks for the offer regardless. Matt .......
285: Tube DIY Asylum, Re: Want to try something new... (0.00)
Posted by mwiebe on 2002-03-18, 07:33:52 (63.230.99.116)
Jeff, It sounds like you have nothing to loose if you try it, maybe some output watts if you can't swing things properly. I have used parallel connected 6021s and 6011s-kind of super minature 6SN7s-t .......
286: Tube DIY Asylum, Re: Ultrapath in PP amps and cathode bypasses (0.00)
Posted by mwiebe on 2002-03-18, 07:08:47 (63.230.99.116)
Ryan, I don't know what is best. But for some reading you may also want to look at few things if you haven't already. Steve Bench reviews a variety of amp topologies (http://members.aol.com/sbench/ou .......
287: Tube DIY Asylum, Re: 829B amp schematic (0.00)
Posted by mwiebe on 2002-03-07, 15:35:49 (63.230.99.145)
Richard, AES has sockets, P-ST7-310, I think they are the same base used for 6C33s. The same base also fits the 832A. Matt .......
288: Tube DIY Asylum, Re: Allied Interstage Transformer (0.00)
Posted by mwiebe on 2002-02-28, 17:59:45 (63.230.99.145)
Yves, When I talked with Edcor about that transformer they said 60ma DC. The transformers are so small it makes you wonder, but they work fine for me. The most I have run through a side was 25ma. Sorr .......
289: Tube DIY Asylum, Re: Allied Interstage Transformer (0.00)
Posted by mwiebe on 2002-02-26, 20:27:59 (63.230.99.145)
Mint, I have been using Edcor's 10K/10K line matching transformer (http://www.edcorusa.com/magnetics/audio/WSM/WSM10k-10k.htm) to do just what you are doing though with much less current. I have been .......
290: Tube DIY Asylum, Re: Recomendations for iron for "Ultra path Pree?" (0.00)
Posted by mwiebe on 2001-11-03, 21:07:47 (63.230.97.96)
I have an Ultrapath using Electra-Print's L3500-C which I love. But I wanted to play around more with the design-Soul Sister et al. So I purchased some 10K/600ohm matching transformers from Edcor (htt .......
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