I, too, own the BP-2000's (original, not TL's), with the CLR-2000 center, BP-X on the sides, and a pair of BP-20's as rears. (BTW, I run a Sunfire Stereo into the mains and a Cinema Grand into the other five; plenty of power.)

I had the mains set to 'large', the center set to 'small', and the rears set to 'large'. I also use a second processor in 3-channel mode to extract a rear-center channel, split to two amp channels, to drive the rears.

I have the second processor's center set to 'large', and the mains (driving the sides, remember) set to 'small', so the surrounds' lows come from the rears, which do bass well. All of this means that only the center's lows were redirected to combine with the LFE channel into the subs.

I originally had the pre/pro's LFE out Y-split to the two low-level inputs, despite Def Tech's recommendations. When I put my gear into the 'hole in the wall', I replaced the links and ran the sub amps with the speaker leads, as I didn't have long interconnects handy.

Of course, I set my pre/pro's bass mgt. to 'no sub', and thus began running my subs in stereo. There was a distinct improvement in the bass quality, not just bass level. I know the LFE channel's signal was split to both subs, as a mono signal, but there was a new, distinct fullness.

However, the stereo sound above the X-over frequency still gave enough directional cues that even the deep stuff seemed to have direction. Since any speaker can reproduce more than one sound at a time, each sub could do half of the mono LFE and the stereo signals' own bass at the same time.

I've read several posts that either suggest, or say outright, that having a mono signal played through two subs ruins their ability to simultaneously reproduce stereo bass, with discernable separation.

Personally, I don't understand why that would be. As I said, a speaker can play more than one sound, so why can't two play stereo audio and a common bass? That's what every two-channel system does with a common bass sound anyway.

Anyway, I recently rewired my speakers again, by removing the links and running a new pair of interconnects, but this time, I used a full-range stereo output instead of a low-pass-filtered output, allowing the subs' LP filters to do the crossing-over, as recommended by Def Tech.

Guess what?! Another improvement in sound. A bit tighter and deeper. A casual play of a bass-test CD shows an increase at 30 and 20 Hz. I sometimes detect stereo separation in even low-frequency sounds.

Let us not forget that all channels are capable of full-range sound, even the LFE if the engineers so choose. There's no reason that 20-Hz bass couldn't be separately recorded in any two or more channels in- or out-of phase, and/or at different levels.

Anyway, I just wanted to point out that there's no technological reason that the non-LFE channels must be devoid of the same deep-bass sounds that the LFE usually carries. The LFE channel is intended for just that: Low Frequency Effects.

Sure, a redirected LFE channel will be mono, but there are plenty of directional cues (harmonics) in the remaining channels, as well as actual low-frequency content, that could certainly benefit from stereo subs, even if it's only a result of phase differences.

There's certainly no harm done.



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Larry Fine
www.fineelectricco.com
My system