Anyone using the Transistor Research LabsM 225's

Tvad,

They are cool at all times. I keep them on 24/7 and even when run hard they stay cool to the touch.

They are now named Samson amps as Bob mentioned above.

I just finished a full review that should post soon.

I owned the Nuforce Ref 9 (not SE) amps and they were cold sounding. Forgot to mention those in my listing of other amps. Had them for a month, but I needed more body and texture then these were capable of. The Samson amps are not Class D, but A/B amps.

Also, a friend of mine owns the D225 amp and it is also wonderful, but the new Samson mono's are certainly better.
Paul and Brian have new learnings and thus the birth of Samson.

I can see why you would think Digital or Class D Grant.

They have far more scale, body, texture and dimension to them as compared to my past Nuforce experience.

It is not Class D, although you are correct that regarding heat distribution it resembles a Class D design. Sonically IMO that is not the case.

It is a well known fact that information and specs on TRL components is hard to come by. While Paul Weitzel measures his equipment the main design goal is the end result which is always about the sound. It is also well documented that specs don't always tell the whole story about a particular component, TRL or others.

So with that said from what I've been able to gather the design is biased Class A up to a certain point, then A/B. Another tidbit that I discovered is that from a current draw this amp design is incredibly efficient. The capacitance within the amp also factors in an immense storage capacity for reserve power when required. That in part is why I think many can equate the sound of this amp to a live experience. Transients are amazing and the amp responds in lightning quick fashion.

The amp is dead quiet and the new power supply design is supposed to be the best yet. Not that the old one or the battery power supplies were shabby either. One thing I can say is Paul has an excellent understanding of electricity and power supplies. Also as a recording engineer he certainly has his own understanding and opinions on live sound.