# Audyssey XT32 + SubEQ HT with no LFE sub



## Snappy (Apr 24, 2009)

Will Audyssey XT32 + SubEQ HT provide the same corrections and work the same way if setting LFE/SUB to no and FR/FL mains to Large? I would like to take advantage of the subs in pure direct stereo mode and other by-pass options I am considering. 

This is for a secondary theater room I want to use primarily for music with occasional TV and movie viewing. Setting sub to no sends all LFE content to the mains. Setting the center and surround channels to small sends 80 and below to the mains. Does Audyssey XT32 + SubEQ HT then offer the same low end correction benefits when engaging Audyssey while listening to movies?

With a Bryston 10B sub active crossover I am able to optimally blend my mains and subs at the common crossover points including 80 Hz. The Bryston allows me to sum stereo to a single sub below the crossover point or use stereo subs. I could add more subs through the Bryston crossover in the same manner anyone using the dual LFE sub outs can.

I searched and understand I may be one of a very few to want to configure a system this way but would appreciate input from those that have tried it and especially interested in results from those that have tested and measured it.

Thank you.


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## Talley (Dec 8, 2010)

It's a good solid question and one that I want to try also.

I want to run my subs through the high level inputs and have two subs one for each left/right main. Not even use the LFE channel... since I"m about 50/50 music/movies right now.

I was curious as to what happens to the LFE channel if set to no sub. It actually does get redirected into the left/right mains?


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## Snappy (Apr 24, 2009)

Talley said:


> It's a good solid question and one that I want to try also.
> 
> I want to run my subs through the high level inputs and have two subs one for each left/right main. Not even use the LFE channel... since I"m about 50/50 music/movies right now.
> 
> I was curious as to what happens to the LFE channel if set to no sub. It actually does get redirected into the left/right mains?



I had a Bryston SP2 that did send LFE to the main FR/FL speakers. I believe most current Processors and AVR’s do it as well but I can’t confirm since my current models don't cover it in any manual or document that I can find. I have a Denon 4520 in the room today but could swap it with an Onkyo SC5508 if needed.

I called Denon and the first level agent was less than qualified to answer or even understand the question.

I’m not on here enough to know forum rules to link to other forums but on the JTR forum there is a thread titled “Which Prepro and Receivers can route LFE to the mains?” A few listed models were tested with claims they do route LFE to mains when LFE is set to no and FR/FL is set to large, which is the default option with no sub anyway.

Assuming the 4520 can route LFE to the mains, I assume Audyssey XT32 will work normally but I am not sure if SubEQ HT would work on channels other than the LFE's. I am surprised it has been so difficult to get an answer. We can’t be the only listeners that prefer to optimize for music versus movie listening.


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## chashint (Jan 12, 2011)

I understand what you want to do.
I am interested in your results, but I only have questions about doing this vs useful input.
Other than to try it out, why would you want to connect the subs like this ?
How will the active crossover work? Will it split the AVR speaker output and send <80 to the sub and >80 to the speakers? How is this different for music than letting the AVR do it? 
Or will you be running your main speakers through the sub? If yes where does the active crossover come into the picture?
I don't know how running the speaker signal through the additional loss and group delay of a high pass filter would help anything?
This type of connection is kind of a throw back to the days before 5.1 channels and AVRs with sub woofer outputs.
My AVR uses distance to phase match the subwoofer's phase to the speakers, if the sub was run off the high level speaker outputs the separate phase matching would be lost (in my case).

Please post more, this is interesting.


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## Snappy (Apr 24, 2009)

_Other than to try it out, why would you want to connect the subs like this ?
How will the active crossover work? Will it split the AVR speaker output and send <80 to the sub and >80 to the speakers? 
_
I would use the Front Right and Front Left Pre-outs of the Denon to the Bryston 10B Sub crossover. The 10B outputs would each then go to external amplifiers to drive the speakers; The High pass would go to the main speakers and the low pass to the sub or subs. The 10B has an option for stereo subs ( I realize there is little stereo content < 80 Hz) or to sum the bass of the FR/FL to a single sub out if I want. I could set the High pass at 80 with a 6-db slope and the low pass at 80 with an 18-db slope. 

_How is this different for music than letting the AVR do it?_

When using the Denon in Pure Direct Mode for two channel music, there is no LFE content so your mains need to handle the entire frequency range. The sub out isn't doing anything. I hesitate to list the other reasons since it seems to bring up debates I am not interested in participating in but I would prefer to take full advantage of the high resolution audio I have purchased in the purest form possible. I even have a DSPeaker 8033 to use if I want but would prefer not to.

_Or will you be running your main speakers through the sub? If yes where does the active crossover come into the picture?_

No.

_I don't know how running the speaker signal through the additional loss and group delay of a high pass filter would help anything?_

There is more loss through the Denon than the very high quality Bryston.

_This type of connection is kind of a throw back to the days before 5.1 channels and AVRs with sub woofer outputs._

I used it for years with exceptional results when I still had a Bryston SP2 surround processor. Granted the Bryston was a very respected pre for two channel audio.

_My AVR uses distance to phase match the subwoofer's phase to the speakers, if the sub was run off the high level speaker outputs the separate phase matching would be lost (in my case)._

The phase options on the 10B handle this quite well by setting the high pass at 80 with a 6-db slope and the low pass at 80 with an 18-db slope.


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## chashint (Jan 12, 2011)

Thanks for that breakdown of the setup.
I had thought of it in terms of the speaker output of the amp running through the sub and on to the speakers.


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