I used to make adjustments on my Classe CA400, but it has been stored away for quite a long time.
I do not know what the current Classe amplifier topology is, but I can try to relate what I used to perform.
There where 2 main adjustments to check;
DC offset and either voltage or current ( I can’t remember which ) across the output devices.
In the center rear portion of the amp was a stack of capacitors and on top of that stack was a circuit board with 4 pots and 4 small ceramic fuses that where mosfet fuses.
2 pots where for the right and left channel DC offest adjustments and 2 pots where for the right and left output device adjustments.
I think that the DC offset had to be adjusted to zero or as close to zero as possible first for each channel.
Then you would take readings across all of the output devices for each channel. There was an average range that the devices had to be within. I say average because with my amp, Classe used a variety of output devices and removed the info off of all of them. I estimated by taking readings, that there were 3 - 4 different output devices. If the output devices average did not fall in range, then you would adjust the pot.
The output devices in my amp where on both the top and bottom of the amp, so both the top and bottom plate had to be removed.
My amp had a main fuse, 4 mosfet fuses and I think 8 rail fuses for the output devices. The main fuse and rail fuses where easy to check in my amp. You must drain the cap bank before trying to check or remove a mosfet fuse, they are charged by the caps at a high voltage, so beware.
I am sorry that I can not be more specific, but it has been years since I serviced the amp.
There was a gentleman over on the Amp/Preamp forum on AudioAsylum that sent me the info.
If you post your need there, someone may be able to help you out or point you in the right direction.
I was not aware that Classe was going through another restructuring. I had a DAC-1 that I needed to have serviced and they repaired it for free, I only paid shipping. I can’t remember the name of their amp tech in service, but he was always able to take my calls.
You may be able to locate a good tech close to you. I had a lightning strike behind my home that damaged the plate amps in both of my Avantgarde Sub225s bass units. Shipping to Germany for repair was $400 one way plus the repair cost. I found a tech that I could ship to for $50 one way and the repairs where only $200.
