a friend has a peavey cs-800 stereo amplifier and i was considering buying it but i wasnt too sure if it would work for powering any kind of speakers. it puts out 400 wpc at 4 ohms and my speakers can take 350 a channel at 6 ohms. Will this amp damage my speakers if i try to use it with them? And is there a lower end stereo preamp i could use with it?