2. amps-preamps
  3. 136143-1060

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
g_nakamoto's avatar
g_nakamoto
348 posts
 
did your buddy buy these new? how long has he had them? are they still under warrenty? take it back to where he bought them. if he bought it from a private party, good luck!
aball OP
2,016 posts
 
He bought them new from a McIntosh dealer, but they are out of warranty by 2.5 years. However, Ayre didn’t care if they were under warranty or not - they repaired them all regardless. In fact, there is a thread about all this on another forum where Ayre themselves posted and said so! Great customer service from Ayre because they realize the amps were defective in manufacturing.

I’ve been a McIntosh owner for the last 20 years. I still love mine (I have 6 Mc pieces right now). I am just disappointed that McIntosh was not willing to do what Ayre did. It’s a bummer. I saw them fully as equals until now. I just hope that my lovely MC152 and my brother’s MC601s won’t develop the same problem...!
g_nakamoto's avatar
g_nakamoto
348 posts
 
kind of strange that both units are over heating.
aball OP
2,016 posts
 
Hi g_nakamoto,  it's normal that both are overheating because they both have bad transistors in them.  The ThermalTrak transistors are the problem (which were made by On Semi, not McIntosh).  Going by the amp serial numbers, there appears to be hundreds of amplifiers with bad transistors in them, so we won't be the only ones with this problem.  We just happen to have experienced it, and, said something here about it.  Unfortunately, only a tiny percentage of McIntosh owners are active in the forums.

While I'm at it, a quick update:  McIntosh told me they would have the built heatsink/transistor assemblies made for us in 25-40 days.  It has now been 40 days and I haven't heard anything, so I sent them an email just now asking for an update.  Fingers crossed they at least come through with this.  Stay tuned.
yuchuinlu
7 posts
 
I was thinking about buying 601 used in the near future. Looks like I need to by 611 instead? Better to save more money now!
More to discover