I find it hard to believe that the pop on power off would have killed an amp - this is the sign of a very bad amp design, at best.

One of our customers has come up with a simple, 2-relay solution to the pop-on-poweroff problem, which is quite neat. Firstly, put a relay in the amp remote line, controlled by the accessory line (so that when the power goes off, the amp gets turned off with the ignition).

Then, connect the empeg's red wire to a permanent 12v feed though another relay. Power this relay from the accessory line through a diode and 330uF capacitor (the value of the capacitor needed will vary according to the size of the coil in the relay):

            diode
accessory ---->|---.----------------- relay coil
                  +|
                   = capacitor
                   |                 
ground ------------.----------------- relay coil

...this gives a good 0.5 sec between amp-off and empeg off.

Hugo