Magtech amplifier over heating.


I bought a magtech amp a few years ago and have had to send it back twice in less than a year. The Motorola thermal track transistors are not reliable. When the thermal sensor goes the amp will become very hot even in idle. The left channel failed back at the beginning of 2015 and then the right channel failed in October.The amp still worked but the heat sinks were very hot even at Normal listening. Roger has no problem with fixing the amp. But how often is this going to happen. I have an Aragon amp that I've had for 30 years and only had it repaired once due to my negligence. Has anyone else have this problem.
buddy2
I had a Sanders ESL amp for almost 6 years and never had a problem with it.

Roger and Angela are fantastic people and will always take care of you. Also their product has a lifetime warranty.

Sorry you've had problems, but just be glad that you had this amp and not some other that only offered a few years of warranty and would have cost you to fix it.
negotiate with Roger so he'll give you another amp and your amp he'll keep on fixin' indefinitely. this will save lots of money shipping it back-fourth. test Roger if he's good enough to make that happen.
You need to know that ThermalTrak have had a bad reputation for failures and SOME models were allegedly discontinued a few years ago.

I suggest you read this thread http://www.diyaudio.com/forums/solid-state/237929-thermaltrak-transistors-have-been-discontinued.html for a typical discussion, but keep in mind it's also true that some other models may be back or are still in production, for example see http://www.onsemi.com/PowerSolutions/product.do?id=NJL3281D

Then read up http://www.whatsbestforum.com/showthread.php?16924-Viola&p=306879&viewfull=1#post306879 on Viola claiming to be getting "low yield", meaning, a lot of dead wood; but the units that did pass QC have had no problems.

The point being is that you should talk to Roger and figure out best course of action, loaded with this info: what models is he using, what's his QC process, why so many failures in your case, etc...

I have also found out through the years that the more expensive amplifiers tend to have a lot more device-matching done on them, and a lot more QC; but this statement is not universal (e.g. have witnessed all too many expensive tube amps blow up and take speaker drivers with them).
I bought one about 2 years ago...It failed shortly after I bought it, and I sent it back. Roger sent me a new amp as he was waiting for a part . The new one failed a bit later , and back it went again.

It runs warm at idle, which I was surprised about, as owners and reviewers commented on how cool it ran. One of my cats loves to sleep on it, as it is like a heated bed!

When operating, it tends to be very warm, and when I listen loudly, it is so hot you can't hold your hand on it for long.

Roger told me that it was being overdriven, as I have Magnepan 3.7's and he stated they are very inefficient, which is so.
I've since turned down the volume, and so far no issues, but the shipping cost for repairs tends to balance out he great price, as does being without an amp for a few weeks.
I love the sound, and have even considered the mono blocks...should it fail again, I'm sure I would discuss other options with Roger.
He stands behind his product, surely.

If it's a QC issue, then maybe my ownership will be shorter than I planned.
A tough call.
So which manufacturer is better one with poor design but nice or one with solid design but not nice?