mesa boogie 20/20 schem

[JC@]

I would need a schematic for this amp. It is the newer all black model, don't now if that matters.
The amp works ok I believe, but I would like to have a look at the bias circuit.

Anybody please?
Thank you

[JC@]

No one please?
With so many tube brands and characteristics, pretending that just plug and play a new set of tubes will be ok doesn't work for me. Too many amps come in with 'charred' glass or sounding horrible because of the nonadjustable preset bias.
I have looked hard in the web for the 20/20 schem with no success.

[Chuck H]

I know you probably want it instantly...Like me. But if the amp is out of warranty Mesa Boogie may send you one. Since the amp is still in production it's a "maybe". But they are generally very helpful if you call.

Chuck

[JC@]

Instantly?
The owner has a venue tomorrow and another one on Sunday!

[Chuck H]

Well since this is Friday you may reach someone at Mesa today. Otherwise it's your a$$.

Call and see if they can Email or fax it. At the very least they can tell you the R#s to target in the bias circuit.

Your sure to get nothing if you don't ask.

Mesa Boogie: (707) 778-6565

Chuck

[Gregg]

http://www.bnv-gz.de/~ooehmann/schematics/mb/20_20.zip

[JC@]

got it got it got it!!!
Thank you

[JC@]

Current draw of the whole circuit is so important in this amp with it's design and little transformers that I soon relized that it would be better to choose the tubes from the 50 box I just received and that was a good decision as at the first attempt I could nail 21mA per tube quite easily and mantain the HT in the plates at 293 volts.
I was lucky I must admit it.
The amp was playing clean and with great dinamics.
Gregg, thanks again, the schematic was very helpful.

[vintagekiki]

mesa boogie 20/20 schem

http://www.about-guitar-amps.com/gui...s/marshall.htm
Registracija je besplatna.
http://www.about-guitar-amps.com/gui..._BackBoard.pdf
http://www.about-guitar-amps.com/gui..._BackBoard.pdf
http://www.about-guitar-amps.com/gui..._BackBoard.pdf
http://www.about-guitar-amps.com/gui...FrontBoard.pdf
http://www.about-guitar-amps.com/gui...ValveBoard.pdf

[shotgunn]

I have been searching for the 20/20 schematic for a while. Any chance someone could share it with me? The above link is now dead... Sorry for the bump.

[Pedro Vecino]

Mesa Mod
See bottom of the page

[vintagekiki]

I have been searching for the 20/20 schematic for a while. Any chance someone could share it with me? The above link is now dead... Sorry for the bump.

The above link is for Marshall 20/20 and not is dead. You must be registered. Registration is free.

Link for Mesa 20/20 is here. See attachment 2020 poweramp.pdf
To see link you must be registered. Registration is free.
http://www.freestompboxes.org/viewtopic.php?f=2&t=1452

Links to Mesa Boogie schematics
http://music-electronics-forum.com/t8403/

[Gregg]

You can get the schematic from this thread:

http://music-electronics-forum.com/t22622/