# When to set to LFE + Mains



## louisp

Velodyne VDP 1000 Sub

How do I determine the correct setting of LFE or LFE + Mains on my Denon AVR? Other speakers are Infinity Alpha 50's, 37c Center and 20's.


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## drdoan

I would try LFE so that all the bass goes to the sub. The best answer, of course, would be to try it both ways. I prefer to send all the Low Frequency Effects to my sub at 80Hz and below. Have fun. Dennis


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## koyaan

louisp said:


> Velodyne VDP 1000 Sub
> 
> How do I determine the correct setting of LFE or LFE + Mains on my Denon AVR? Other speakers are Infinity Alpha 50's, 37c Center and 20's.


If you have your Main speakers set to "large" on the Denon, LFE will send only the LFE channel to your sub. lfe+mians will send lfe to your sub and send the main channel signals both to your main speakers and your sub.
With Alpha 50s you probably need more bass than the main speakers will produce alone, so this might help, though it will double the bass on those frequencies that both the sub and mains will produce.
If you have your main speakers set to "small" everything below the crossover will go only to the sub anyway.

Best I recall, the Denon doesn't have an selectible crossover point, but simply crosses over everything set to small at 80hz. This is why you need to fiddle around with this setting a bit, your alphas will go well deeper than 80hz before they start rolling off, so you just need to try both and see whitch sounds best.

Hope this helps.
Good luck!


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## Mike Cason

I have the Flagship Denon 5308CI(A) AVR and there is a full setup menu for xover points for all of your speakers, including the center backs. It's a very useful tool. You can also set up the THX default. I disabled this feature and fine tuned my speakers accordingly. Most of my speakers are DIY and modified Bang & Olufsen for side surrounds.


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## Owen Bartley

I like to start with LFE + Main for large speakers. I kind of figure it's a shame to have nice big towers that can play low and not use them, but sometimes it does muddy-up the sound, so I'd agree with a listening test both ways, and then just pick what sounds good to you.


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## gdstupak

Onkyo calls it 'Double Bass' and I use it. Although from the write up in the manual, it seems to share the bass from the main channels with the LFE output, but does not send the LFE signal to the mains.
So, I think my mains are only getting the signal from the L/R mains, and my subs are getting the LFE signals + the L/R main siganls.

My JBL towers can easily handle freq down to 30hz and my outboard amp still has plenty of headroom. 4 subs sounds much better than 2 subs!
The JBL's bass sound (i.e. upright bass, bass guitar, tom tom's, pipe organ) is more realistic than either my HSU sub or Tempest homemade sub. I like to hear the bass that comes out of the JBL towers, and I like to feel the bass that comes out of the outboard subs.


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## Owen Bartley

I don't know of any system that sends the LFE channel to the mains, I don't think, unless you have the sub set to "none". Glenn said it better than me... if your mains sound good down low, then use 'em! 

Ideally if you had good extension from the mains, and an adjustable crossover on the processor, you would be able to bring it down so there wasn't overlap in one region which might make things sound bloated or boomy if the subs are playing over top of the mains. I checked my setup at home and I'm running LFE+Main, and I like it. I kind of figure that if you aren't using the towers... why not just go with a sub/sat system instead?


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## gdstupak

Owen Bartley said:


> I don't know of any system that sends the LFE channel to the mains,


I thought my old Yamaha AVR had a setting to do that, but I might be remembering it wrong.


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## caper26

This is a confusing topic for some entusiasts. First thing is first, we need to get something straight:
*There are 2 kinds of "Bass". *

The LFE channel (the .1); and 
the low frequency components in the main mix (all the channels minus the LFE).
The only way the LFE will go to mains is if you have NO SUB, and set the receiver LFE setting to "NO sub", or "Mains only" or whatever. (Usually this is not the standard option for most HT users)
Next comes the meaning of "Large". This usually means a FULL RANGE speaker capable of delivering deep bass accurately. 
Next comes Crossover setting (XO). What is it? How does it work? Basically it is a filter for the low frequency components that get re-directed from the other speakers to the subwoofer.
Next comes the setting in the AVR: "LFE" and/or "LFE + Mains". There are different combinations available here, and this is where it gets tricky and confusing. You have to consider the XO point, whether your mains are full range, and whether you want deep bass played through your mains or not, in addition to your sub.
For someone like me with flat panel speakers, the answer is easy. I select my LFE setting to "LFE", since I want any deep bass in the main mix to be redirected to the sub (in addition to the LFE channel which ALWAYS goes to sub in my case).
Someone with full range speakers, may want to experiment with LFE and 'LFE + mains'. In such cases, depending on the AVR, only the bass from the surrounds will get redirected to sub and/or mains. Also in this case, the PHASE setting becomes important since you have more than one source for bass. 
Hope this helps!!
~cape


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## louisp

Thank you for this very clear explanation.


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## caper26

No problem. Hope it helped some.


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