As The_Lhc's post. From personal experience iv'e found it depends on the amp, Denon 1910, Yamaha 767 were / are fine. The Pioneer 1017 i prevously had, it strangled, so plugged it straight into the wall, was fine after that. My advice for A/V Amps or amps in general, would be to try it with & without to hear which is best, it wont do any harm.
All my kit, except the subwoofer, is plugged in to one now.
Regards.....