Oh how I wish Class D amps ...

Ckoffend - I might be wrong about heatsink since they talked about ADDITIONAL heatsink (module has its own) but I don't really know If REF100 has additional heatsink (picture shows some heatsink).

Continuos power rating doesn't make much sense anyway since average music power delivered is only few percent of the peak.

"Atmasphere, OK. But FWIW, there should be no problem with almost any preamp, tube or transistor, driving a class D amp.

From my non professional experience. I was immediately taken by my first switching amplifiers lack of fatigue and its unusually transparent presentation. It did, however, pose some difficult issues regarding RF and/or EMI. An afternoons worth of a VAC upgrade and the RF issues were resolved. Now I was hearing my tube preamp, its noise and sonic colorations. After some extensive auditioning I found my current battery powered solid state preamp to be a key partnering with my switching amplifiers technology.

I agree, there shouldn't be a problem with other preamps and to a great extent there aren't. Still, the isolation of a battery powered pre proved to be a surprising sonic advancement in my system. Partnering the H2O with the Fire pre is another example.

I'd like to mirror Muralman, switching amplifiers require system refinement to varying degrees. Cable materials and size, shielding, and VAC supply all play a large part in system refinement.

All my amplifiers have their shortcomings but the switchers have far less. They are different and they do have their own presentation. None that I've auditioned even come close to sounding like a tube amplifier or solid state.

I'll add that my OHM F5s are about as power hungry as they come. I bought the Bel Canto ref1000ms as a low or no compromise solution for reasonable cost. I like to play music that should be loud, loud. The BC has fit the bill perfectly. They are the first amps I have tried (of 3) that have never run out of steam no matter what I do. THe music just continues to expand and inflate as I increase the volume to whatever high level might be needed. No signs of stress or distortion and one often does not even realize how loud things are until you try to hear somebody near you talk.

I cannot find any fault. Some might prefer a more lively top end I suspect, but the top end is all there quite nicely. That's about it.

"Continuos power rating doesn't make much sense anyway since average music power delivered is only few percent of the peak."

I think that is the essence of how a switching amp is able to achieve the performance levels it does in such a small and energy efficient package.

Regardless of design, in the end, its all in the execution. How well does a product do its thing. The better Class D amps these days would seem to indicate that the answer is "really good", even if not to everyone's particular taste.

"No signs of stress or distortion"

- that might be due to line and load regulated power supply in your REF1000. 99% of the other amps have completely unregulated supplies - that is why class AB amps have monstrous size toroidal transformers and a lot of capacitors (to minimize voltage drops).