Amplifier gets HOT on one channel, shuts down - any ideas? Class CA-2100 (not PS Audio)

My Amp, which is a Classe CA-2100, has been acting up. It has a status LED light in front that usually stays Blue, but lately, the left channel LED turns RED and it shuts down. Whenever that happens when I goto the Chasis, the LEFT SIDE is extremely HOT! Like super hot to touch. NOT the right side.

The company is in restructuring so I am trying to see if I could get any support, but being a computer engineer and knowing a few things about electronics, is there a way for me to test and see what component is failing? I have access to multimeter to do some measurements if necessary.

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.

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This Classe Amp doesn’t have those setting at least visibly. I opened it up and can’t see anything visually alarming.

However, I THINK I fixed it, and it maybe something completely unrelated to the Amp. The left channel banana plug was LOOSE, so I THINK the connection was cutting in/out and probably putting too much load on the left side. I fixed that and will see if the problem goes away!

I was gonna say flip flop all connections. Speaker cable… preamp hookups etc. see if the problem changes sides

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Maybe message Darren. If memory from the various forums serves, he used to work at Classe before joining PS Audio, and may have a few ideas.

Thanks. I actually think I fixed the issue by fixing the speaker connection. It sure seems to have been the issue. So far so good. Btw, I opened up the amp and it’s a BEAUTY! Great construction and materials. Here are some pics. Highly recommended in the used market.