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.