I've considered adding a small sub (6.5" or 8") to my 2-channel/home theater rig for quite some time. I was curious as to whether or not I could add a sub without adding an extra amp. Could I power my two speakers and sub off of my 7 channel receiver? Could I use channel C to power the sub and install a low pass filter inline with it? I'm not looking for room shaking bass, but rather just something to add a little more punchiness and even out the low end of my LSi9s.