Distributed subs actually works in a normal room which is more than you can say about bass traps.
For bass traps to work in the low bass they have to be unrealistically large. And if you have that then you are probably listening in an anechoic chamber which at least to me sounds horrible.
For bass traps to work in the low bass they have to be unrealistically large. And if you have that then you are probably listening in an anechoic chamber which at least to me sounds horrible.
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indeed - FWIW, the smaller or more irregularly shaped the room, the less practicable I've found bass traps to be in a listening room or "home theatre" in a real world domestic environment
Let's be honest, not all of us have the luxury of dedicating the physical space or financial resources to achieve "perfect" sound - whatever the current definition of that is
just as it's been said that politics is the art of the possible, audio in the home is an art of acceptable compromise
In my case I have a 15"x16" dedicated room so I can do, for the most part when ever I want. I also have a shop so making traps or subs is a no brainer.
So, what I am hearing is that distributed bass does the same thing as traps, but traps would have to be very large to do the same thing....do I have that right?
So, what I am hearing is that distributed bass does the same thing as traps, but traps would have to be very large to do the same thing....do I have that right?
It is not the same, it is attacking the problem from two different ways.
Problem is standing waves.
All rooms have standing waves. These are determined by the dimentions of the room. A cubic room will have a lot of coinsiding standing waves with a lot of energy at few frequencies, making the freq response in the bass really ugly ... as the sound.
More irregular rooms have a better spread of the standing waves on the freq line, making the damage less.
In a really large room the standing waves will be spread out over a larger frequency area
making the freq response much more flat. So large rooms means better sound in the bass.
Placement of sound source and listener is also very important, as you can come to sit in a peak zone ... bad.
Bass traps trys to dampen the standing waved, sucking out energy and also lowering the reverberation time.
Multiple subs will ensure that more and different standing waves are "hit" making more an smaller peaks, which if many enough will add up to a even freq response. But they will not help the reverberation time.
In essense I would do some of both if I had the possibility, getting an even spread of the standing waves, and lower the reverberation time.
But place the damping carefully not to take out a lot of energy in the mid and high.
Also large diffusors can help (e.g. a whole wall rounded or the ceiling .... I have done both in my HT) .. this will also spread out the standing wawes ..... diffusors are much better than damping with regards to sound quality.
(Building a Home Theater and Listening Room)
Best regards Baldin
Problem is standing waves.
All rooms have standing waves. These are determined by the dimentions of the room. A cubic room will have a lot of coinsiding standing waves with a lot of energy at few frequencies, making the freq response in the bass really ugly ... as the sound.
More irregular rooms have a better spread of the standing waves on the freq line, making the damage less.
In a really large room the standing waves will be spread out over a larger frequency area
making the freq response much more flat. So large rooms means better sound in the bass.
Placement of sound source and listener is also very important, as you can come to sit in a peak zone ... bad.
Bass traps trys to dampen the standing waved, sucking out energy and also lowering the reverberation time.
Multiple subs will ensure that more and different standing waves are "hit" making more an smaller peaks, which if many enough will add up to a even freq response. But they will not help the reverberation time.
In essense I would do some of both if I had the possibility, getting an even spread of the standing waves, and lower the reverberation time.
But place the damping carefully not to take out a lot of energy in the mid and high.
Also large diffusors can help (e.g. a whole wall rounded or the ceiling .... I have done both in my HT) .. this will also spread out the standing wawes ..... diffusors are much better than damping with regards to sound quality.
(Building a Home Theater and Listening Room)
Best regards Baldin
Dennis - assuming the "standard" 8ft flat ceiling, that seems like a rather unfortunate set of dimensions - particularly in the area around 80 & 140 Hz and sub/ harmonics thereof. I'd be inclined to experiment with a combination of randomly located multiple smaller subs ( i.e. no larger than 10" each) and treatment. Of course, well placed or easily mobile pieces of large upholstered furniture can achieve some of the latter.
As I recall, some very interesting work, including measurements and suggested placements in Tooles' book - mentioned severally elsewhere - "Sound Reproduction .... "
Sound Reproduction: Loudspeakers And Rooms By Floyd Tool Loudspeakers, Rooms, and Books Aren't Perfect Review By Howard W. Ferstler Boston Audio Society Speaker Volume 31 No. 1
As the above reviewer notes , neither rooms, loudspeakers, or those commenting about them are perfect.
If not already in your library, should probably be considered essential reading, along with Earl Geddes' work. While we're at it, for a more personal and philosophical take on the listening experience writ large, the two by Daniel Levitin -"Your Brain on Music", and "Six Songs"
Dr. Daniel J. Levitin ? Neuroscientist ? Musician ? Author
As I recall, some very interesting work, including measurements and suggested placements in Tooles' book - mentioned severally elsewhere - "Sound Reproduction .... "
Sound Reproduction: Loudspeakers And Rooms By Floyd Tool Loudspeakers, Rooms, and Books Aren't Perfect Review By Howard W. Ferstler Boston Audio Society Speaker Volume 31 No. 1
As the above reviewer notes , neither rooms, loudspeakers, or those commenting about them are perfect.
If not already in your library, should probably be considered essential reading, along with Earl Geddes' work. While we're at it, for a more personal and philosophical take on the listening experience writ large, the two by Daniel Levitin -"Your Brain on Music", and "Six Songs"
Dr. Daniel J. Levitin ? Neuroscientist ? Musician ? Author
More or less yeah, they would have to be pretty much as big as the room, hence "unrealistically large". And if you really want it to work then just adding bass traps won't cut it, you pretty much want to build a room inside the room where the floor, ceiling and walls can flex (constrained layer damping). If you do all that then sure, you will damp bass. You will damp everything else too so it won't sound good of course but you should absorb a lot of bass reflections.
OR you could get a multisub arrangement.
The best solution for bass IMO is a nearfield bass solution. Basically design your room so your main subwoofer is 1 ft or less from your normal listening position. You can put in other subwoofers if you want, but that main one will dominate the response at your ears, and it's response will be significantly less impacted by room effects.
Thanks for all the input. I have two very good subs and two KLH subs from Costco. Sounds like I should attack the issue from both sides. Right now I have a massive one note bass and it is driving me crazy.
I can fit 210 cu ft of bass traps in the back of the room and corner traps in the front of the room from about 3 ft up from the floor to the ceiling. I plan I building the traps for the back of the room with plastic on one side under the cloth so I can use it as a reflector of sorts if it sounds too dead.
I can fit 210 cu ft of bass traps in the back of the room and corner traps in the front of the room from about 3 ft up from the floor to the ceiling. I plan I building the traps for the back of the room with plastic on one side under the cloth so I can use it as a reflector of sorts if it sounds too dead.
Hi djn,
Just some thoughts:
With acoustic or electronic notch filters you are trying to cut out the nodal room response peaks. With multiple subwoofers you are trying to create a listening area in the room in which the direct and the reflected sounds balance out to an overall equal sound experience. To me these are very different but possibly complementary actions.
To make distributed subs work you will most probably need individual level and phase controls for the subs. Either on the individual subwoofer amplifiers, or in a control module (e.g.: dsp). If you just drive a bunch of subwoofers from the same source that does not qualify (it's a start though). The location of the subwoofers has to be really distributed, e.g.: as per the Geddes multiple small sub approach.
For a 15'x16'x8' room a LEDE (life end dead end) approach could be used to remove basically one of the reflective surfaces, e.g.: a very absorbtive wall behind the listening position combined with a relatively live front wall (or the other way round). An elevated seating area could be used as a large bass trap. Curved reflectors at the sides of the listening area would improve the overall dispersion; the rear of these reflectors could be bass traps.
As I said, just pondering.
Regards,
Just some thoughts:
With acoustic or electronic notch filters you are trying to cut out the nodal room response peaks. With multiple subwoofers you are trying to create a listening area in the room in which the direct and the reflected sounds balance out to an overall equal sound experience. To me these are very different but possibly complementary actions.
To make distributed subs work you will most probably need individual level and phase controls for the subs. Either on the individual subwoofer amplifiers, or in a control module (e.g.: dsp). If you just drive a bunch of subwoofers from the same source that does not qualify (it's a start though). The location of the subwoofers has to be really distributed, e.g.: as per the Geddes multiple small sub approach.
For a 15'x16'x8' room a LEDE (life end dead end) approach could be used to remove basically one of the reflective surfaces, e.g.: a very absorbtive wall behind the listening position combined with a relatively live front wall (or the other way round). An elevated seating area could be used as a large bass trap. Curved reflectors at the sides of the listening area would improve the overall dispersion; the rear of these reflectors could be bass traps.
As I said, just pondering.
Regards,
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