If your head unit doesn't have an amp turn on/off option, your amp may have a gain adjuster that will allow you to turn it on or off or your other option (which is quite simple) would be to wire a switch up in parallel with the amp turn on lead.
98' Contour SVT
#607 of 6535
05' Mazda 6s
Audio/Visual enthusiast because it's one of the many things I went through 4 years of hell for
