Booming Bass

[Spartan88]

Hi all,

Looking for ways to tame booming bass.

Watched Tenet last night which is rather bass heavy anyway but it really seemed to boom.

Front speakers are a pair of Technics Hi-Fi speakers on Fisual Dynami stands (two columns front larger than rear) and a small, old Yamaha centre with an old Yamaha sub.

Potential problems below:

- When soundtrack plays I can feel reverberation down through the speaker stand. The speakers are sitting only on small rubber pads, only a millimetre or two thick.

- The centre is sitting directly on an Ikea Besta Unit and reverberation can be felt through this.

- Sub was turned down quite a bit. It sits directly on the floor and is somewhat trapped in a corner. I will find it difficult to reposition. Does it need feet/legs/isolation from the floor?

Floor itself is suspended wooden floor with laminate flooring. The majority or the space between the speakers and listening position is covered by a thick, heavy rug.

All speakers are being replaced at some time in the near future but want to tame the bass with these and whatever new speakers are deployed. Assuming some mix of feet/isolation for the speakers and perhaps something to fill the stands if that will lessen the reverberation.

Any suggestions received with thanks.

 

[BriD]

Do you have the ability to move the sub around the room a bit? Is it in a corner?

 

[Stuart Gray]

What receiver are you using?

 

[MI55ION]

What source are you using?

Sounds like you have an issue where bass frequencies <250hz are exciting room modes. For illustration, the giant peaks you see on this graph would cause the "boom" to dominate you're listening experience.

You can lessen the effect somewhat by blocking all ports in your speakers/subs so there is less output at lower frequencies. Also moving the sub/speakers and listening position away from corners and walls can have an effect.

Whatever speakers you buy in the future will likely have issues at the same frequencies. Even when optimally positioned, some combination of room absorption and electronic EQ would go a long way to help. Some receivers have built in auto EQ or room correction specifically to combat what you are experiencing. There is also the option of plaback software that support EQ if your source is a PC.

Really depends how deep you want to go down the rabbit hole. If you have the time and inclination consider getting a usb microphone and Room EQ Wizard.

 

[Spartan88]

Do you have the ability to move the sub around the room a bit? Is it in a corner?

It is tight to a corner at the moment. I may be able to move the sub permanently by moving some bookshelves around (that are against the same wall. Sub will still be close to back wall and between bookcase and TV unit but with more room. I will test again tomorrow with sub pulled out of the corner into the room.

What receiver are you using?

Yamaha RX-v767

 

[Spartan88]

What source are you using?

Sounds like you have an issue where bass frequencies <250hz are exciting room modes. For illustration, the giant peaks you see on this graph would cause the "boom" to dominate you're listening experience.

View attachment 1453944

You can lessen the effect somewhat by blocking all ports in your speakers/subs so there is less output at lower frequencies. Also moving the sub/speakers and listening position away from corners and walls can have an effect.

Whatever speakers you buy in the future will likely have issues at the same frequencies. Even when optimally positioned, some combination of room absorption and electronic EQ would go a long way to help. Some receivers have built in auto EQ or room correction specifically to combat what you are experiencing. There is also the option of plaback software that support EQ if your source is a PC.

Really depends how deep you want to go down the rabbit hole. If you have the time and inclination consider getting a usb microphone and Room EQ Wizard.

Speakers are 6-8 inches from wall. Can't pull forward more than another inch or so as they'll encroach too much into room. No ports in speakers, sub is front ported.

 

[Spartan88]

Answered some questions above.

Any action I can take re isolating speakers from stands and or filling them, if so what with?

Likewise, how best to reduce transfer of base from centre into TV unit and sub into floor? Feet or pads to isolate?

 

[BriD]

I'd first experiment with the sub pulled out from the corner of the room and take it from there

 

[Gasp3621]

I don´t think any feets under the sub do much. Moving it out from corner to example 1/4 - 1/3 front wall length should help with the boominess. Try side wall too or rear wall as a nearfield location if not close to corner.

If you have some package foam you can try that under the sub. It does basically same thing as these which cost so much:
Amazon product

 

[MI55ION]

Answered some questions above.

Any action I can take re isolating speakers from stands and or filling them, if so what with?

Likewise, how best to reduce transfer of base from centre into TV unit and sub into floor? Feet or pads to isolate?

If isolation is your only concern, these should do the trick for both the sub and speakers. There are more expensive options.

Amazon product
I doubt however it'll make much if any difference to the overall room boom.

 

[Spartan88]

If isolation is your only concern, these should do the trick for both the sub and speakers. There are more expensive options.

Amazon product
I doubt however it'll make much if any difference to the overall room boom.

I'm thinking that this thread has the wrong title.

Using the word Boom has clearly given the impression that the bass sound is bouncing off walls and surfaces where in fact, the issue I've identified is one of sound travelling through objects such as the speaker stands, TV unit and floor. Not that I won't check for reflected sound/bass also.

I don't have feet on the sub so would need to stick something to the underside or just sit it on top.

 

[MI55ION]

I'm thinking that this thread has the wrong title.

Using the word Boom has clearly given the impression that the bass sound is bouncing off walls and surfaces where in fact, the issue I've identified is one of sound travelling through objects such as the speaker stands, TV unit and floor. Not that I won't check for reflected sound/bass also.

I don't have feet on the sub so would need to stick something to the underside or just sit it on top.

Sounds like you have diagnosed the issue. The term you want for vibrations traveling through your speakers and into objects is "resonance", this can manifest as things rattling, muddying of the sound, incoherence and some degree of boom.

Isolation and decoupling speakers/subs from whatever they are on is a good way to significantly reduce if not eliminate this type of resonance.

A subdude type platform as linked to above (smaller platforms available for speakers) or even the rubber washing machine isolation feet can work well here.

Standing waves and build of bass modes etc that people more commonly identify as boom is a whole different ball game. Feel free to come back if the above doesn't work for you.

 

[Spartan88]

Some remedial action taken.

Bought some small rubber feet at a local 'hardware' store. Very small at 10mm wide and 5mm high but did a good job of separating the centre from the TV unit.

Stuck them on the bottom of the sub also but too small to make a difference I think.

Pulling the sub out of the corner softened things but that was mainly because it placed the sub on the rug.

If I were to use these pads under the speakers (L/R), do I stick them to the top of the stands or to the bottom of the speakers?

 

[MI55ION]

Pulling the sub out of the corner softened things but that was mainly because it placed the sub on the rug.

Curious, how do you know it was because of the rug and simply not the action of pulling it out of the corner?

 

[Spartan88]

Curious, how do you know it was because of the rug and simply not the action of pulling it out of the corner?

That should have read 'likely' or 'possibly' rather than mainly.

What I shall have to do is stick it back in the corner as see how things are with the centre speaker partly isolated from the TV unit which I think has helped.

Is there a way to isolate each part of the system ie switch off all but the sub and see how it sounds, switch off all but the centre and see how it sounds etc?

 

[Stuart Gray]

Try the test tones from the receiver in set up.

 

[Spartan88]

Try the test tones from the receiver in set up.

I shall try that tomorrow.

 

[Spartan88]

Just watched a movie, Pacific Rim, so plenty of crashing and banging.

Moving sub out of corner (still on the laminate flooring) had little effect. Moving it onto the Rug more so. Still so thumping through the floor that I had to turn it down.

Shall try some feet/pads to isolate from floor.

 

[twooper]

You can try lowering the crossover frequency at the amp. My sub is crossed at 80hz and I have 12" drivers in my fronts so I only need the sub for LFE. Basically you should cross where the fronts don't go.

 

[Maxson]

Just watched a movie, Pacific Rim, so plenty of crashing and banging.

Moving sub out of corner (still on the laminate flooring) had little effect. Moving it onto the Rug more so. Still so thumping through the floor that I had to turn it down.

Shall try some feet/pads to isolate from floor.

A low tech way that I used in the past is a doormat doubled up under the sub, then a small concrete paving slab under that which was on top of carpet. The carpet and mat are a form of resilient damping and the slab has mass to help decouple the mass of the speaker from the floor. This makes a homemade acoustic sandwich - carpet, concrete, rubber mat. So I was able to enjoy bass without annoying the neighbours.

Also carpeting the whole floor with good carpet and underlay including under all your speakers will help absorb resonance and improve the sound of your system. Having a rug in the middle is the opposite of what is needed as the corners of the room is where you most need material that will absorb sound.

 

[miguelbarroso]

What is the model of you yamaha sub?... if it's a low end unit, it's boomy by nature... that kind of monotone bass, coming out of the sub port. Not much you can do but to replace it.

So you can have an idea... I had a cheap Eltax sub, not very powerfull and a lot of that one note boominess... when I replaced it by a REL Strata III, although bigger and much more powerfull, the boominess just disapeared... just clean, punchy bass! Nowadays there are a lot of nice subs with good performance.

As for the vibration from the centre channel, I would raise the crossover on that channel and see if it improves anything. If the centre speaker is of much worse quality than the front LR speakers, I would consider either upgrading it or at least not having centre speaker at all.

 

[natman]

Go the the home and garden store and get a paving stone. Get a couple of carpet samples to put on top and below it. Put your sub on top of it. It's hard to transmit much vibration through an inch of cement.

Make sure your sub isn't just boomy. Many are. Some internal cross braces can make a huge difference.

 

[unbound59]

I'd first experiment with the sub pulled out from the corner of the room and take it from there

Agreed