How to add woofers to Wadia, Classe, Wilson setup?

I recently purchased a pair of Entec SW-5s to supplement my system.

I'm not happy with the bass I'm getting from my Wilson Watt Puppy 3/2's

My front end is a Wadia 860 connected via balanced outputs to a Classe CA-2200 Amplifier--no preamp. I'm using volume control via my Wadia. My dip switches on the Wadia are set to output very low voltage so I can keep my volume control in the upper range.

Now for the problem. I hooked up the Entec crossover to the unbalanced output of the Wadia. The Entec's didn't put out much sound since the voltage was far below line level.

So I think I'm going to have to hook up my pre-amp (an adcom 750) for volume control and set the Wadia switches to output true line level outputs.

Should I continue to feed the Entec crossover with my Wadia or should I hook it up to one of the sets of unbalanced outputs from the pre-amp?

I hope this makes sense.