Search found 51 matches

by Nyquist5
15 Dec 2011, 13:46
Forum: Amplifiers
Topic: matamp series 2000
Replies: 15
Views: 5125

Re: matamp series 2000

Yes, GZ34. I forgot to mention it on the schematic. At least on GTO I had in used diode rectification instead of valves. As I said, there are many vairations on the theme. If you build one, put the effect loop switching jacks the right way round so that you don't run the risk of burning the return t...
by Nyquist5
12 Dec 2011, 12:03
Forum: Amplifiers
Topic: matamp series 2000
Replies: 15
Views: 5125

Re: matamp series 2000

Yep, that's my schematic, visible at nicosonic.com . This is the schematic of one version only of the GTO/2000. I traced it from pictures but got several other Matamp in for repair after that. The amp's design varies (amongst other things, different phase splitter circuits can be used) but I am glad...
by Nyquist5
05 Dec 2011, 09:45
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Marshall - Supa Fuzz (196x) [gut shot picture thread]
Replies: 207
Views: 92034

Re: Marshall SupaFuzz

You mean the Erie electrolytic on the right? That one's contemporary to the pedal. I think Marshall even used that type in some amps. Yes, I know, I have a marshall superlead with those in :wink: . But the way it has been installed on this board tells me it was soldered later on in the pedal's life.
by Nyquist5
30 Nov 2011, 09:23
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Marshall - Supa Fuzz (196x) [gut shot picture thread]
Replies: 207
Views: 92034

Re: Marshall SupaFuzz

Yes, this pedal has been through rough times. The board is damaged and pretty much every single screw has been lost and replaced with an inappropriate one. And a Boss PSU was hardwired to the board, through a hole drilled in the front of the casing... :roll: Talk about throwing money out of the wind...
by Nyquist5
29 Nov 2011, 11:10
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Marshall - Supa Fuzz (196x) [gut shot picture thread]
Replies: 207
Views: 92034

Marshall SupaFuzz

Hey there, Nothing that isn't known about this SupaFuzz, but it uses AC126 so I thought I'd share the guts with you. One Electroytic cap does not seem original and the pots have been changed. It has been well used and abused. Apart from that, it seems stock. The sound is pretty mushy due to failing ...
by Nyquist5
26 Sep 2011, 20:33
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Roger Mayer Voodoo Bass
Replies: 2
Views: 3513

Re: Roger Mayer Voodoo Bass

Yep, the pots are cheap and even a good cleaner won't solve the scratchy problem for very long. I like my Roger Mayer Octavia and Voodoo Axe but the latter one can by very ear-piercing. It works EXTREMELY well in the normal channel of a Marshall Superlead though (and this is why I never modded it).
by Nyquist5
12 May 2011, 10:12
Forum: Amplifiers
Topic: Weber Z-Matcher
Replies: 12
Views: 8028

Re: Weber Z-Matcher

Peavey used to sell the "Automatch" transformer (4, 8 and 16Ohm taps). They still sell a version with different taps...
Otherwise, you should be able to find autotransformers for this application in good electronic component stores.
by Nyquist5
18 Apr 2011, 13:44
Forum: Amplifiers
Topic: Matamp GT/C7 schematics
Replies: 4
Views: 2491

Re: Matamp GT/C7 schematics

I have updated/corrected versions of the C7 and GT schematics. I should be posting them soon on my website...
by Nyquist5
31 Aug 2010, 18:23
Forum: Modern Stompbox Effects (1975 - ...)
Topic: EHX - Big Muff Pi 1977 & 1978 version [schematic]
Replies: 109
Views: 51197

Re: IC Big Muff [schematic]

I own 3 of them (2 in the Little BMP format) and I agree with the fact that you can get pretty close to the SP tone in Siamese Dream. Definetly more so than with a transistor BMP. I put a small cap accross the clipping diodes on mine to remove some of the fizz (I often do that), and it is true that ...
by Nyquist5
15 Dec 2009, 10:32
Forum: Amplifiers
Topic: New Matamp schematics
Replies: 0
Views: 1380

New Matamp schematics

Hi,
I have already published a partial C7 schematic here but I have now traced the Series 2000 schematic. So here they are:
Matamp 2000
C7
Feel free to give me more info on the C7 if you have one (tonestack values, etc...).
by Nyquist5
09 Nov 2009, 16:09
Forum: Amplifiers
Topic: Little help repairing a Carvin Legacy ??
Replies: 6
Views: 1608

Re: Little help repairing a Carvin Legacy ??

It appears that at least one of the power tubes has conducted current from cathode to heater as R79 has burned up. This could have been caused by improper bias, simple tube failure or a failing component in the bias circuit. A burnt up PCB becomes conductive. This means that you need to replace it o...
by Nyquist5
30 Oct 2009, 07:51
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Some great Stand Alone effects units..
Replies: 49
Views: 10042

Re: Some great Stand Alone effects units..

Of course you are right.
Nevertheless, from a "market" point of view, it is analog and that's news to me!
by Nyquist5
29 Oct 2009, 16:48
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Some great Stand Alone effects units..
Replies: 49
Views: 10042

Re: Some great Stand Alone effects units..

Is it because it is the end of a hard day's work or I am right in saying that this DC50 is in fact analog. I can see the "digital" part in it :scratch:
by Nyquist5
22 Oct 2009, 16:23
Forum: Amplifiers
Topic: Questions about the Sovtek Mig50
Replies: 3
Views: 1181

Re: Questions about the Sovtek Mig50

The insides of Sovtek amps vary wildly from model to model. Yours may be an original one even if the innards don't look like other ones you've seen on the net. However, there is a guy on ebay selling Mig 50s that are not original. The transformers he puts on original chassis are undersized (usually ...
by Nyquist5
07 Oct 2009, 09:18
Forum: Amplifiers
Topic: Help with a Sunn Concert Bass?
Replies: 26
Views: 7086

Re: Help with a Sunn Concert Bass?

I had the same problem with my late 70's Concert Lead that I got for very cheap (plus the 6x10 cab :applause: ). I replaced all output transistors and drivers with similar or higher rated components. Now it works like a charm for either guitar or bass (circuit is the same as the Bass model). These t...
by Nyquist5
23 Jul 2009, 10:07
Forum: Amplifiers
Topic: PEavey Deuce | in half?
Replies: 10
Views: 4993

Re: PEavey Deuce | in half?

I will try this, i never biased the deuce because you dont have to bias the amp.. (its a fixed bias) Not in the schematic you posted: look at the 50k pot on the first page... If your amp doesn't have it, it is advisable to modify it to this schem's topology (with all due precautions when working on...
by Nyquist5
23 Jul 2009, 07:13
Forum: Amplifiers
Topic: PEavey Deuce | in half?
Replies: 10
Views: 4993

Re: PEavey Deuce | in half?

Hi Andersom, To reduce power output, simply remove the two outmost 6L6, and rebias accordingly. To do it properly and ensure that the output valves see the right reflected impedance, you'd need to plug a dummy jack into the Main output (to open the connection to ground) and connect the speakers to t...
by Nyquist5
23 Jul 2009, 06:48
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Boss - DS-2 Turbo Distortion [schematic]
Replies: 2
Views: 2080

Re: boss turbo distortion [schematic]

The turbo switch adds the Q23 stage as a sort of "boost" to intensify the downstream stages overdrive.
by Nyquist5
17 Jul 2009, 06:54
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Roger Mayer - Voodoo Axe [schematic]
Replies: 10
Views: 5537

Re: Roger Mayer - Voodoo Axe ( schematic ) [schematic]

From memory, the "Axis Fuzz" transistors are 2n3906 and 2N3904, and the input buffer transistor is BC549C.
P2 is indeed linear and P1 is 2,2k.

I don't have the pedal at hand but I can check within a few days.