I believe all equipment will worked best within their comfort zone, I recommend use the sub line-output high pass the signal to feed the power Amp, your Amp and speakers will thanks you for doing that.
Best Subwoofer Connection
OK, so I'm waiting on delivery of a JL Audio e110 subwoofer. I have a 2 channel setup. The on-line manual recommends connecting the preamp outs to the subwoofer's line in (l/r), and then going from the sub's line outs to the power amp. OTOH, I could just go from the second set of preamp outs to the sub's line in and run the signal in parallel without using the sub's internal xover. Which connection is preferred and best for a music only setup? I've searched this issue here, but I haven't found an answer that makes sense to me. Thanks.