Sounds like you've had audiophile heaven experience a few times.My problem is I have a set of Alpine 6 1/2 spr17 coax's rated for 110rms/330 peak and sound outstanding being pushed by an Xtant 604x but you probably know by reading that statement that i'm putting way too much power too these coax's.I agree;gain settings input 3/4 up and output gain 1/4 up,getting Alpine's crossover's smokin' (burnin out the ceramics).They can't handle the high power.What do ya suggest other than lowering gains even more?I have the x-over settings set pretty high to keep the bass out,but as you may or may not know Xtant is just a guess without guages to verify exact settings.Thanks