In the interests of making sure I don't inadvertently blow something up:
Is it OK to leave my front speakers plugged into my Yamaha HTR-6160 while testing another set of speakers via the front pre-outs on the Yamaha, hooked up to a power amp (Hafler 9505)? If I can just leave the front speaker wires attached and jump back and forth between the old speakers being driven by the 6160 and the new speakers driven by the Hafler by unplugging the preouts to the Hafler things will be marginally easier for me.