Might be a dumb question but how will I know how much power this amp will make with my speaker setup? Specs on amp say 150 watts per channel @ 8 Ohms and 200 Watts per channel @ 4 Ohms. Per Chet, from Deft tech he said set the amp in 4 ohm mode as the speakers are 4-8 ohm. So how do I do this? Or will the amp already know what power to make by just hooking up the speakers.