I doubt that 12TC’s rather high capacitance is bothering the Bryston enough to result in extra heat.
There is always some heat from a power amp; as Erik said, whatever power it’s drawing winds up as heat. The B3 series runs cool compared to some of the competition. I tried a Pass X250.8, which puts out 400 watts of heat at idle -- as much as the heater I use to warm the audio room in the winter.
If the heat is a problem in your room, I suggest you look into some of the newer Class D amps. I’ve heard great sound from them, and they run cool.
P.S. I had a 14BSST, and loved it very much -- except when I had to move it.
There is always some heat from a power amp; as Erik said, whatever power it’s drawing winds up as heat. The B3 series runs cool compared to some of the competition. I tried a Pass X250.8, which puts out 400 watts of heat at idle -- as much as the heater I use to warm the audio room in the winter.
If the heat is a problem in your room, I suggest you look into some of the newer Class D amps. I’ve heard great sound from them, and they run cool.
P.S. I had a 14BSST, and loved it very much -- except when I had to move it.