Uber expensive repair at United Radio

This thread is delivering on every level

"...I feel like a cheap old bastard :-). Final reply on this subject..."

I feel your pain, $2000 for a repair is a lot of money but if it goes back in service for another decade or more, probably well spent.  

Just realize the subject of the thread, when I finally looked in..

Classe 600 monoblocks.
I nearly worked on one, once (last year). I regained my senses at the last minute... and since classe had been reborn, so to speak, I had the store involved send it back to classe.

I’ll take on just about anything, electronically, a good electronics fistfight and beatings (emerge with black eyes but triumphant) or whatever... but that amp ... is a bit of a bear, to say the least. This, when I spent a good 20 years repairing audio commando style --- no schematics, ever. Is one a tech or a board swapper? Lets see who’s really got it, or not...can you hang with the tough crowd, or will you crash and burn? What does one do when discipline, logic, brains, and patience are required?

Any tech looking inside of it and seeing what it is.... and dealing with a ’ghost in the machine’, with overbearing unknown software that serves as a lock out on error.... means that finding that ghost, from a position of ignorance about the circuit... makes buying lottery tickets look like a better idea.

One of those ones that should be left with the orignal company that made it. They are really not all that common, these overbearingly complex unknowns about complex unknowns... but this is one of them. I hate giving in and and rarely do, but this was one of those rare times.

These are not all that common and you are from the Kingston area?

Maybe it was your amp that I turned down repairing...

A lot of very good points made by many here.  Very good posts.

As some mentioned, exactly how long does it take to diagnose where exactly the problem is?  That actually takes more time than pretty much anything else.  The OP mentioned two chipsets.  Well, how long did it take to find that the problem was the two chipsets? 

Typically, unless the amp displays error codes like modern cars, the tech has to start in certain sequence and move forward.

For example, disconnect everything from the power supplies and see if the power supplies are actually working.

If so, connect one side of the amp to the power supply, see if it works, then disconnect that side and connect the other.  Slowly bring up the voltage.

These are just small examples. 

Diagnose the protection circuitry, etc.  yep, I hate to tell you but, these take some time.  Unless I knew exactly what the problem originally was, I would take my time and go in sequence.
So, the time spent, actually does make sense to me.

I work on electronics all the time and I also restore classic cars and I work on cars also.

I own and restored a 1983 Volvo 244 Turbo.  It had a low oil pressure reading on the gauge and the idiot light.  Know what the problem was?  wasn't the gauge or wiring, wasn't the oil pump, bearings, etc.  it was a stupid five cents o ring on the oil pickup tube.  yep.  had to drop the oil pan (stupidly difficult on this car), had to move the steering rack and lots of other things to get that oil pan off, remove the oil pump tube.

This took an entire weekend.

So, having worked on (and still to) and repair and upgrade audio equipment, I can tell you that although it took them some time, I can see why it might have.

enjoy

Alt take: original fault that damaged the chipset fries them again.