George, note though that one of the OP’s concerns was heat generation. A pair of XA-160.5 monoblocks apparently draws a total of 1200 watts, all the time (when powered up), since it is biased in class A. While the power consumption of his Ref150 is spec’d as 420 watts at idle, and 730 watts at rated output. So the Pass will generate a good deal more heat than the Ref150.
A similar issue would arise with most comparably powerful class A amps, whether tube or solid state.
Regards,
-- Al
A similar issue would arise with most comparably powerful class A amps, whether tube or solid state.
Regards,
-- Al