What is the correct way to connect the SVT-4 Pro with the BBE Bmax preamp? At the rear panel of the Ampeg there are lots of inputs & outputs. I read the user manual but I confused! I use the Ampeg with an Ampeg SVT 410HLF Heritage cabinet. The cab is 500W RMS and the amplifier is 1600W at mono-bridged mode and 625W when I use only channel A. So I think it's safer to use the 625W. So, how should I connect the external preamp BBE to the amplifier with an external loop?