Acoustic Foam Thickness (Too Thin?)

[frank1985]

A year ago I purchased 8 2ft X 2 ft panels of acoustic foam (eggcrate design) for use in an isolation cabinet. I'm now thinking of using these to treat my bedroom (9ft X 10ft) for mixing. The thing is, they're only 3 cm thick and am in a bit of a dilemma as to whether I should stick with these or spend money on thicker tiles. Are these tiles sufficient or would I need to replace them with the latter? I was thinking as a compromise that I could maybe ditch 4, and replace them with a couple of 10 cm thick tiles.

 

[ecc83]

Just what my flypaper mind has picked up about acoustics over 50 years but....

I would make 4 x 2x2 6cm panels out of them and then mount those in a frame that spaces them some 5 to 10cms from the wall...WHERE you put them is a whole new ball game!

Maybe Ethan can spare a mo' even if only to give me a slap?

Dave.

 

[frank1985]

Appreciate the reply.....but I've heard that there's no acoustical benefit of gluing eggcrate foam together.

 

[ecc83]

Appreciate the reply.....but I've heard that there's no acoustical benefit of gluing eggcrate foam together.

Din't say glue it! You'll block up all the little holes! Just lay one on top of the other. In fact there might be some mileage in spacing one sheet 5cms or so from 'tother?

This of course means this is just of eggbox FORM? Actual eggboxes do acoustic jack S.

Dave.

 

[mjbphotos]

'Acoustic foam' - the Auralex brand - will absorb highs. The 'no-name stuff, less-so. If 'flutter echo' is what you are trying to cure, then use it but note that you may end up with a 'dead' room that still has major low end issues. Bass traps are needed to cure these, and they work equally well on absorbing highs.

 

[frank1985]

'Acoustic foam' - the Auralex brand - will absorb highs. The 'no-name stuff, less-so. If 'flutter echo' is what you are trying to cure, then use it but note that you may end up with a 'dead' room that still has major low end issues. Bass traps are needed to cure these, and they work equally well on absorbing highs.

Ok i've looked into bass trapping and I found these: Bass traps for studios and home cinemas : 4 x Pro-coustix BassBlox eXtreme bass traps 305mm

I'm thinking of getting two sets for £200; that's 8 traps in total (two in each corner). Does it seem like a good deal to you?

 

[RAMI]

Ok i've looked into bass trapping and I may have found a good deal here: Bass traps for studios and home cinemas : 4 x Pro-coustix BassBlox eXtreme bass traps 305mm

I'm thinking of getting two sets for £200; that's 8 traps in total (two in each corner). Do you think with 8 bass traps I'll be able to get away with using the thinner unbranded tiles at the early reflection points? You mentioned that the BTs absorb the highs as well, so maybe my acoustic foam can act as a mere refinement?

Those" bass traps" are made of foam, which means they're probably useless. You really shouldn't be using foam at all, other than for small spot placement here and there. Foam does nothing for your low end, literally. So all you're doing with foam is killing your high's and mids, and doing nothing for your lower frequencies. This leads to a "dead" sound when you clap your hands, but doesn't solve the fact that you have bass frequencies out of control, and bass is 99% of the problem in 99% of rooms, so you definitely need bass traps. Problem is, even though that company calls their product "bass traps", they're not bass traps at all.

You need rigid fibreglass, rockwool, or a few other proper materials. Foam is not one of them. There's very little, if any at all, use for foam in properly treating a room. Don't waste your money.

 

[frank1985]

Thanks for the heads up! Do you know of any reputable manufactures in the UK that produce fibreglass and/or rockwool traps? I'd rather buy them already made rather than go down the DIY route (don't have time)

 

[RAMI]

Thanks for the heads up! Do you know of any reputable manufactures in the UK that produce fibreglass and/or rockwool traps? I'd rather buy them already made rather than go down the DIY route (don't have time)

Hopefully someone in the UK can help you out. I know of REALTRAPS which is in the states. Ethan Weiner, who is a member here, owns that company. There's also JBrandt, who is a member here. I think he's based somewhere in Africa, believe it or not, but might have some connections in Europe. There's also GIK Acoustics, who is also a member here, but I'm not sure if they're American or British.

You could probably find some contact info on these people if you go to the Studio Build forum section and look them up.

 

[RAMI]

Here's GIK Acoustics' UK section:

Acoustic Panels | Bass Traps | Diffusors | GIK Acoustics Europe

 

[frank1985]

Cheers dude

 

[mixsit]

A year ago I purchased 8 2ft X 2 ft panels of acoustic foam (eggcrate design) for use in an isolation cabinet. I'm now thinking of using these to treat my bedroom (9ft X 10ft) for mixing. The thing is, they're only 3 cm thick and am in a bit of a dilemma as to whether I should stick with these or spend money on thicker tiles. Are these tiles sufficient or would I need to replace them with the latter? I was thinking as a compromise that I could maybe ditch 4, and replace them with a couple of 10 cm thick tiles.

I gave up, tried to find a source to confirm this, but re; 'foam only does highs', doesn't foam (acoustical foam that is) absorb about* as well as 'glass and rockwool?
* -note being real general here..
Mainly the thing with foam being the nice huge double gotchas'- price per depth, and- also adding to to the cost likely, those nice stylish cuts, that basically reduces a " 2 inch depth " product effectively to 'an inch and a half worth of absorption?

 

[RAMI]

I gave up, tried to find a source to confirm this, but re; 'foam only does highs', doesn't foam (acoustical foam that is) absorb about* as well as 'glass and rockwool?
* -note being real general here..

I guess it depends on how "general" you want to be.

There's no way I'd be able to find it now, but I've seen specs that show that "foam" doesn't affect anything below something like 200hz or something, can't remember.

Massive Master, Ethan Weiner, J. Brandt, GIK acoustics, etc......all have mentioned time and time again that "acoustic foam" is not only almost useless, it's almost an oxymoron to put the words "acoustic" and "foam" side by side.

I think it's all about density and gas resistance. So, even if you doubled and tripled up your foam so that it's 12" thick, it still won't control any low end.

I'm basing all this on what I THINK I know, based on what I THINK I understand from what I THINK I've read from people who's opinions I THINK I respect.

 

[mixsit]

I guess it depends on how "general" you want to be.

There's no way I'd be able to find it now, but I've seen specs that show that "foam" doesn't affect anything below something like 200hz or something, can't remember.

Massive Master, Ethan Weiner, J. Brandt, GIK acoustics, etc......all have mentioned time and time again that "acoustic foam" is not only almost useless, it's almost an oxymoron to put the words "acoustic" and "foam" side by side.

I think it's all about density and gas resistance. So, even if you doubled and tripled up your foam so that it's 12" thick, it still won't control any low end.

I'm basing all this on what I THINK I know, based on what I THINK I understand from what I THINK I've read from people who's opinions I THINK I respect.

I'm real good to go with that. 'Specially since that would be the bottom line!

 

[frank1985]

RAMI, it looks as though I'm going to only be able to fit 3 bass traps into the corners of my room, mainly due to there being two large shelves at the front right corner of my space. Would it be wiser to just use two on the backwall corners, and maybe one or two on the frontwall between the speakers?

 

[RAMI]

RAMI, it looks as though I'm going to only be able to fit 3 bass traps into the corners of my room, mainly due to there being two large shelves at the front right corner of my space. Would it be wiser to just use two on the backwall corners, and maybe one or two on the frontwall between the speakers?

Hey Frank,

I hope someone with more knowledge than I have comes in to this thread. I'm far from being an expert in this kind of thing, but learned a thing or two along the way when I was getting my room together. I'm not sure what the right answer to your question is, so all I can do is tell you what I did. I have the same problem as you; one of my corners has a staircase, so what I did was I just went with treating the 3 other corners. I figured symmetry in this case is less important than treating as many corners as I could.

That's my personal situation. Whether I did the right thing or not will hopefully be answered by others.

 

[DM60]

I guess it depends on how "general" you want to be.

There's no way I'd be able to find it now, but I've seen specs that show that "foam" doesn't affect anything below something like 200hz or something, can't remember.

Massive Master, Ethan Weiner, J. Brandt, GIK acoustics, etc......all have mentioned time and time again that "acoustic foam" is not only almost useless, it's almost an oxymoron to put the words "acoustic" and "foam" side by side.

I think it's all about density and gas resistance. So, even if you doubled and tripled up your foam so that it's 12" thick, it still won't control any low end.

I'm basing all this on what I THINK I know, based on what I THINK I understand from what I THINK I've read from people who's opinions I THINK I respect.

+1, that is just pure honesty.

 

[frank1985]

Here's a crappy pic of my room layout...



The red dots are dead cert bass trap locations; the Q marks signify possible alternatives. The X indicates the problem area with the shelving

 

[ecc83]

Here's a crappy pic of my room layout...

View attachment 82392

The red dots are dead cert bass trap locations; the Q marks signify possible alternatives. The X indicates the problem area with the shelving

Like most of us Frank, the room is so small that you are practically forced to sit in the worst possible position, dead centre.

Re sound absorbing materials. I am going to replace "I THINK!" with "AFAIK" and AFAIK it all comes down to size and wavelengths.

AFAIK absorbers work by converting air particle velocity into heat. Thus the more of a "wave" that is in the material, the greater will be the attenuation (AFAIK!). This means that for long wavelengths the material must be much thicker.

Then AFAIK, this also explains why spacing panels off walls improves their efficacy. At the rigid wall the particle velocity is zero! Also a spaced absorber gets two bites at the cherry. The incoming wave and the reflected one.......AFAIK!!!

Dave.

 

[RAMI]

Like most of us Frank, the room is so small that you are practically forced to sit in the worst possible position, dead centre.

Re sound absorbing materials. I am going to replace "I THINK!" with "AFAIK" and AFAIK it all comes down to size and wavelengths.

AFAIK absorbers work by converting air particle velocity into heat. Thus the more of a "wave" that is in the material, the greater will be the attenuation (AFAIK!). This means that for long wavelengths the material must be much thicker.

Then AFAIK, this also explains why spacing panels off walls improves their efficacy. At the rigid wall the particle velocity is zero! Also a spaced absorber gets two bites at the cherry. The incoming wave and the reflected one.......AFAIK!!!

Dave.

AFAIK, I agree with you. I THINK.