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If my subwoofer has no LFE input...

I am considering a new subwoofer. Many very nice, but older models do not have inputs appropriate for LFE from a processor. Given that the subwoofer would be connected in parallel with the main speakers:

1. Can most processors be told not to send LFE to the sub channel and direct all low frequencies to the mains?

2. What kind of sonic degradation occurs, from a home theatre perspective, with this kind of setup (presumably the 2 channel sound would be excellent)?

Any help/information is welcome. Thanks very much.
ssblount
gunbei
2,327 posts
 
No problem at all.

Sounds like the Audio Physic cabinets will make a good looking and good sounding combination!

Good luck.
richingoth
326 posts
 
If I remember correctly the Denon AVR receivers have in the speaker, subwoofer menu (when set to on) THX and THX + Mains. So if a subwoofer is not connected to the sub pre out you could still get the LFE info to your Left and Right Main speakers when set to THX + Mains.
Regards
Rich
richingoth
326 posts
 
In the above post the correct nomenclature is LFE, so subsitute LFE for THX (in the speaker configuration, sub menu on the on screen display). ie. LFE and LFE + Mains. Sorry for the confusion.
nighthawk
241 posts
 
Rich, the only way to get the LFE content in the mains is to select the no subwoofer option. The LFE, LFE+main is what goes to the sub, not the fronts. I've tried both, and greatly prefer the LFE only going to the sub. LFE+main causes some weird phase cancellations between the sub and full-range mains. However, this can be a good way to use the sub to extend the range of nearly full-range (40Hz) mains set to large. You set the sub output to LFE+main and set the sub's crossover to a very low frequency, such as 30Hz, to provide bottom fill only. This works better for audio than HT.
richingoth
326 posts
 
Nighthawk, according to my DENON AVR-4800 manual and the on screen display you have to set the subwoofer to "On" to get to subwoofer mode screen: "LFE -THX-" or "LFE + Main".
That is you have the flexibility to choose how the bass information is distributed to your speakers if you have large front left and right speakers and a subwoofer as part of your home theater speaker system.
By selecting the "LFE + Main" option, you will be sending the same bass frequencies to both the front left and front right, AND to the subwoofer speakers simultaneously.
If the "LFE -THX-" option is selected, bass for the large front left and front right goes ONLY to the front left and front right speakers. Bass going to the subwoofer comes from the LFE signal and any speakers which you have designated as "Small".
I believe this is the only way for DENON receivers to get an LFE signal to the front speaker outputs so that a subwoofer with no LFE RCA input could ultilize it's high level speaker inputs.

http://www.usa.denon.com/catalog/pdfs/avr4800dfu.pdf
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