I've always found Yammy amps to be quite "slow". At the tv station I used to work at, we had Tannoy passives (system 800? Can't remember...hated them) being driven by an old P2100...and the combo kinda worked...tamed the fatigue factor somewhat. Out of interest, I hooked up my Chevin Research amp to see if the Tannoys would work better with a blindingly fast amp. Result: Completely unlistenable. Hard. Sharp. Earbleedingly brutal. Made JBLs seem DULL.
But...
The old Yammy's were reliable, built like tanks, and pretty good bang for the buck...and in 10 years at that joint they never ever broke down.
Cheers,
Tim