FrankHarveyHiFi:
Well I'm going to fly in the face of what seems to be common opinion - I've just been running the SCM11's off the 8XPD, and while it sounds ok - can't help thinking it could be better - the 8XPD isn't enough for those that like slightly louder volumes. I ran it for about half an hour at-20dB, and it was almost sizzling hot - so obviously this isn't going to do the job for those that like a decently long and loud enough listening session. For me, I'd like to know there's a bit more in reserve, but I'd have been scared to turn it up any louder or run it for much longer. It will be the same results with the SCM40's, as their sensitivity is the same.
There may be many people out there running this range on amps with less power than the 8XPD - all I can say is they must be listening to their systems at background levels, average levels, or for short periods of time. Whatever the opinions, this is proof the 8XPD isn't enough to run the SCM range safely or sufficiently. I stand by my recommendation, and the other guys here, of a pre/power combination for the SCM series.
Not quite sure I understand - maybe the 8XPd's natural operation is to get hot - like Class A amplifiers? Also, you don't mention the adverse effect on sound quality, if any?