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Posted By: MarkHB Setting Dual Subwoofer Distances & LFE + Main - 01/31/22 07:52 PM
I have two subwoofers, both connected to a single output on my Denon AVR. When I use Audyssey it obviously provides me with one distance (that doesn't match the distance to either of the subs from the sweet spot). Should this distance be altered? Doesn't this impact when the subwoofer signal reaches my seat vs the other speakers?

I'm also getting conflicting advice on-line about whether set subs to LFE or LFE+Main in a 5.2.2 home theater system. Your thoughts?
Hi Mark

Are the subs equidistant to the main listening position? If so you might be fine.

I would recommend set to LFE and set all speakers to small with a crossover of 80hz to begin. If you are using small satellite speakers you may want to increase your crossover as required.

Im not a fan of LFE+Main. It may work in some rooms if the subwoofers arent placed or sized correctly. You are just artificially bolstering bass content by 6db or so below 120hz. With two subs set in opposing sides or front wall at 1/4 points you dont need to enable LFE+main.

You just need to calibrate your subs to mains correctly. Im not sure on your level of comfort with measuring tools, but to do this properly with multiple subs you cannot use an automated process. To add to this, if your subs are corner loaded the phase distortion caused by their placement makes it especially tough. Lots of output though…

Let us know if you want to go down the manual path. If auto is your speed then I would leave as LFE with 80hz and trust audyssey unless you hear boom or “slow bass”.
Originally Posted by TrevorM
I would recommend set to LFE and set all speakers to small with a crossover of 80hz to begin. If you are using small satellite speakers you may want to increase your crossover as required.

The magic number is 120hz I believe or else you will loose all the sound on the LFE channel between 80-120hz as it will be simply dropped by the receiver in the configuration you suggested.
Correct. The LFE (sub) channel is a discrete channel with content mixed 120hz and below.

The LFE setting and speaker crossover setting are two different things.

The crossover point for other channels is not related to the LFE in the way you state unless you use LFE+Main where bass content below the crossover point in the “small” channels is mirrored to the LFE and L/R channels.

You should NOT use LFE+Main if you care about system headroom in your amplifier. Time aligning your mains to subs and group delay will also be less ideal. -But a good idea if spl quantity is the goal for sure.
WRONG!!

After reading the x6700H manual settings section the bass region from all speakers is added to the LFE output when LFE+Main is selected. Vague and yucky. Lol.
Haven’t done any critical listening but things seemed much better on LFE vs LFE+main. I’ll try some movies this weekend.
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