H.T. newbie - Subwoofer questions...

Hi everyone, I'm new to home theater - just purchased a Denon AVR4800 receiver, surrounds, center channel and subwoofer. I hooked everything up and it works GREAT, but I have a question about the subwoofer. It's a Klipsch KSW-12, and I would like to use it for both home theater AND just audio. The way I have it set up now it's only being driven when in THX or surround modes because I don't have my main speakers (Martin Logan Sequel electrostatics) plugged into it - they are just hooked up to the receiver. If I understand this correctly, I can unplug my MLs from the receiver and plug them into the right and left outputs of the sub and then plug the sub into the right and left outputs of the receiver so it will then "catch" all the low frequency signals before they hit the MLs, thereby eliminating the ML subwoofers, which is fine by me. Is this correct? Also, would I just leave the other connection to the subwoofer output of the receiver so when I'm watching a movie, it will process the low freq stuff that way? What would happen if I was listening to music in stereo mode and then switched to 5 channel stereo? Would both the front speakers and the subwoofer output be driving the sub at the same time??? Any advice would be greatly appreciated. Thanks!
This can get quite complicated. You can send the signal into the sub, use its crossover so that it sends the rest of the signal (all frequencies above whatever you set the sub's cross-over at) to the mains, and set up your processor so that it thinks there's no sub. Most processors send the LFE effects to the mains when set up that way, so they'll go to the sub. You'll also get sub action when playing CD in 2 channel. There's a couple of annoyances with doing it this way, though. You'll probably want to use different crossover points for music and HT, as LFE effects can get up to 100 or 120 hz. Second, I've heard that sub, and I gotta throw my two cents in here - it would be a crying shame IMO to have it producing base in frequencies that the martin logan's could. those are much better speakers than the klipsch. Third, and perhaps most importantly, inserting the sub in the signal path from the main amp to the speakers will almost always degrade the sound quality.

Most surround processors have a built-in crossover, such that whatever the source is (DVD, CD, satellite, whatever), you can select a frequency, below which the signal is sent to the sub. With some processors it just sends the frequencies above the crossover to the speakers, however with some processors you can decide whether you want that or to have the entire signal to the speakers. Running them 'large' means they will sound the same as they always did, and the sub will be an addition at the lower frequencies. Running them 'small' means they produce the frequencies above the crossover, the sub produces the frequencies below it.

However, if you'd like to do it the other way, it will work.
Hey Dbw1,

thanks for the response. I did some testing with the sub and the settings on the receiver and found that it does indeed send signals to the sub in 2 channel stereo mode without hooking the speakers up to it. I agree with your advice about the MLs reproducing LFs better than this sub, so I got out my manual for the sequels and set the sub right at the point where the MLs picked up the LFs. It sounded pretty good, but I still may mess with it some more this weekend. Thanks again for the advice!!