does anyone have a CM Labs 911 Schematic


does anyone have a CM Labs  911 Schematic

Hi anyone I´m looking for a CM Labs model 911 Schematic,
 any help will be Great!--
 I cant seam to find one or a CM Laboratory   911
I have a 2v dc off set problem I think it should be 0v.
I checked all caps and resistors all ok I just replaced the main B+ caps
unit works OK but for the 2v dc on both sides of the speaker outputs that I  cant adj out 
also the balance and bias controls are wire wound pots I am wondering if I can 
get away with 1 watt or smaller on these controls?

madman2000
Thank you very much that solves the wave form balance problems
also I have a good schematic now but it does not show the wattage of the pots 
or  where to get and how much bias voltage should be.
I may have to buy the schematic and hope it is in there.
I never could get a answer from Mr Wayne Chou I hope he is OK.
and he is just a busy guy.
thanks again.

The 8mv from the output is due to the leakage current of the output capacitor, I think your amp is over 40 years old so best to replace those caps.
The 911 is a single rail power supply, output capacitor coupled power amplifier, I don't think you can adjust "DC offset" on this amp. I believe the "balance adjust" pot is to adjust the voltage before the output capacitor (at the + side of the cap) for max output without clipping, in most case is half the value of the power supply rail voltage.
It's best to obtain a service menu for bias and balance adjustment.
Good luck
ok I get 8mv with a 8 ohm load but balance adjust doesn't do much stays at 8mv also 3v across ? ohms on wire pots = ? wattsalso what points do I measure bias adjust from and what are they set at ?
unit works OK but for the 2v dc on both sides of the speaker outputs that I cant adj out
Did you connect a load to the amp output to do the measurement?
The 911 has a output capacitor, if no load connected, it will show some DC reading!
also the balance and bias controls are wire wound pots I am wondering if I can get away with 1 watt or smaller on these controls?
You can measure the voltage across the pot to calculate the wattage required.
Hope it help, regards
 
cool I could not find anything- thanks much but it is to hard to see the values of the resistors and caps in this photo plus I need the part numbers also again thanks for the try. color me still looking.---
If you’re a forum member of either diyaudio.com or audiokarma.org, you can contact him through those site.
His last post at audiokarma was Aug 2018, at diyaudio his last post was May 2008, so the best site to contact him will be audiokarma:

https://audiokarma.org/forums/index.php?threads/cm-laboratories.216659/page-2#post-11851274

If all you need is just the CM Labs model 911 Schematic, this is one:

https://www.diyaudio.com/forums/attachments/solid-state/128876d1236871919-labs-35d-cm911-copy-jpg

You need to be a diyaudio.com member to open it.

The designer of CM Labs 911, Wayne Chou, is a active member of audiokarma.org, maybe he can give you some help.

https://audiokarma.org/forums/index.php?threads/cm-labs-preamp.315531/

There's a downloadable online service menu for $10.95

https://www.analogalley.com/osccart/product_info.php?products_id=789