Quote Originally Posted by kexodusc
Second, would there be any drawback to hooking the second sub up by splitting the signal from my receiver to the 2 subs?
Thanks
That would give you a mono signal to the subs. You lose any advantage of stereo bass you may have otherwise achieved.

An alternative approach is to connect each subwoofer to the left and right channels. Set the main speakers to large. If the amp has preouts on the mains, then you can feed this signal to the subwoofers and use the low pass filter on the subwoofer rather than the bass line level output. In parallel you take the preout and also send it back to the "main in" for the main channels. If you don't have this facility, then you can take speaker level inputs which most sub plate amps can accomodate.

As I'm fairly new to HT I can't comment too much on this approach, but I imagine a downside to this is that you don't get remote control of the bass level relative to the other speakers.

Parts Express have a tutorial on this which discusses hooking up a sub in more detail.