10dB resonant peak at 40Hz

Yes, DSP would do it. I'm not using a sub.

Last speaker was the JBL L82 and even the KEF LS50 Meta (which I did not think even went to 40Hz) does it. If I plug the speaker ports, the resonance goes away but so does too much of the bass.

@erik_squires you mean THIS?

I’ll try moving them around this weekend. Right now, they are 50" out from front wall and 30" from side walls. I did calculate 15 ft resonance is 37 Hz - sounds about right.

Since plugging the ports worked, sealed box may be another idea but would need a larger cabinet.

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.

The best way to break up standing waves is by using subs placed asymmetrically about the room. They must not be active above about 80Hz else they will attract attention to themselves.

This approach to dealing with standing waves is known as a Distributed Bass Array. If your main speakers make decent bass, you really only need two subs to sort things out.

I have not had much success with DSP or room treatments. I think the best solution is get 2 subs but where do I put them?

My current speakers only go to about 70hz so low bass will only be from the subs. I was looking two The Cube Active Acoustic Suspension Subwoofer but open to other suggestions.

My room is 13 x 15. I can try to single sub aimed at the wall.

Does it help if the speakers do not go below 70Hz?

@deep_333 

Modal peaks will ’linger’ and kill all your room resolution.

Not clear what you mean. The 2 subs will produce this? Timing is important to me. If they can not integrate properly might as well forget it.

The subs have variable phase control. Are 2 subs enough? Not real clear about placement.You mean 1st sub 1/4 of the length and next to he wall on the width? The second sub on opposite wall  placed 3/4 of the length? Which way do they aim?

I think I was missing the point. You are using a subwoofer to break up the 40Hz standing wave produced by the loudspeaker? Not to produce bass itself?