McIntosh (MC601) amplifier overheating problem


Hello everyone - A buddy of mine has MC601s that have recently started overheating.  Each amp went into protection mode after emitting a burning smell, and both had to have an output transistor replaced (at different times).  

My internet digging has revealed that ThermalTrak transistors are not very reliable, or at least the early batches were not.  Ayre has also reported overheated MX-R amps with the same problem.  They apparently can fail after years of use, which is not good news for owners!

I'm trying to get a feel for how widespread this problem may be (at this point in time)?  Each transistor replacement is $400, and there's an awful lot of output transistors in MC601s...!!  I convinced my brother to also get MC601s so I'm starting to get really worried his will fail too in the near future.

So far, McIntosh's response to my inquiry has been vague and reticent, unlike Ayre who apparently went to great lengths to remedy this issue for their owners.  Has anyone out there had this problem with McIntosh or Ayre?  

aball

Showing 1 response by biketony

I had the same overheating problem with a mc-352.  I have two and run them mono. I bought both used. The unit in question would overheat then shut down.  Then after a few would come back on. While the other would not have any problems with the same input. Eventually the unit made a Burning smell and shutdown for good.
Took the bad unit to a authorized service center in royal oak Michigan. They went through it found what they thought was wrong and reassembled. They then wanted to make sure that they had solved the problem, so they ran the unit for a few days on their bench, and the same problem occurred. It fried again. They went back in and replaced a whole side of output transistors. (I saw the bag of transistors they replaced, it was a bunch).
 The whole process of th repair took almost 6 weeks (evaluation, ordering parts, labor, testing, evaluation, ordering parts, labor, testing). In the end the bill was $650.00.

So with the repair cost of $650.00 and the $2700.00 I spent on the unit I have $3350.00 into a mc-352. It’s not the greatest deal I ever made, but I wouldn’t say that I am unhappy with my purchase.