No Sub-Mojo

I have an Accuphase E-202 integrated amp that I'd like to use with a subwoofer since it has preamp/main out outputs. I tried to connect to a sub a few months ago, but was not able to get a signal to activate the sub. Anyone out there who has an E-202 and is using it with a sub? This is confusing to me, because I also have a Pioneer Spec-1 preamp that I'm using the preamp outputs to drive a sub, and that works beautifully.

Maybe you can try connect the sub to 'MAIN IN' instead of 'PRE OUT' while the switch is at 'NORMAL' position. If no signal output to the sub, next thing to try is using a 'Y' adapter connect one end to 'PRE OUT' and the other end to 'MAIN IN' to loop the signal back to power amp section. The sub connect to RCA female end and set the switch to 'SEPARATE'.