10dB resonant peak at 40Hz


Hi all, room is 13' x 15' and am getting a 10dB room resonance at 40Hz

How to eliminate? Can't move the speakers and room treatment would need to be minimally invasive.

cdc

Your thoughts?  

@mashif 'It depends'. If the subs are only active below 80Hz than interactions won't be a problem unless you place them side by side and operate them out of phase.

If you have only one sub (and its only active below 80) then its a matter of placement; you have to move it around bit by bit until you find a spot (which you may already have found) where all frequencies can be heard at the listening position. Two subs makes that go a bit easier; 3 even more so and you really don't need to go past 4.

My room has a pretty bad bass cancellation at the listening position and my speakers are flat to 20Hz. To break up the standing wave causing the problem I added two subs- one to the left of the listening position and the other to the rear and a bit to the right. It was pretty easy dialing them in.

Thanks for all the responses. So there are many options to address this problem.

Walking around the room, the bass is more resonant in the corners and near the back wall. I listen above 3 feet from the back wall and even there is audible.

My personal conclusion: this is a room, not a speaker problem. There is nothing wrong with the speakers per say. Second, I have not had good success with DSP as it changes the FR but also degrades the sound quality. Third reducing sound at 40Hz does not address the problem. Sure the hump is gone but I think I would loose bass quality as what is left is still a resonance and not music.

So looking into it as a room problem, I tried moving the speakers around and nothing helped. If there is some magic spot, I could not find it.

- One foot front the front wall.

- Middle (7 feet out) of the room.

- Speakers 5 feet apart up to 10 feet apart.

If you want to test your system, I play Madonna’s " I don’t search I find". When she drops that depth charge at 0:46 my room goes kaboom.

I heard back from GK Acoustics and they say "you’ll need a decent amount of coverage all over the surfaces of your room" with 10.5-17" thick panels to get any decent attenuation.

So it looks like Atmasphere’s "Distributed Bass Array’ is only viable solution.

Second, I have not had good success with DSP as it changes the FR but also degrades the sound quality.  Third reducing sound at 40Hz does not address the problem. Sure the hump is gone but I think I would loose bass quality as what is left is still a resonance and not music.

What did you use for DSP?

 

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Your concern about hearing resonance rather than music can be addressed by a combination of HP filter and sub. By reducing the energy below 60hz in your mains and REPLACING it with a sub with DSP that you can move around, you would have some control over the low end. The SVS subs have great DSP software that can tailor the FR precisely in the low end without affecting the overall SQ of your mains.