Rehearsal room acoustic deadening, best cheap solution?

[maxrossell]

My rehearsal room is basically a brick box with pretty high brick ceilings, so the sound tends to bounce around a lot, making everything sound quite undefined and a lot louder than it actually is. We get a lot of unpleasant high midrange, but the floor is wooden boards with a bit of thin carpet so we lose a lot of the bass end punch and warmth to unsympathetic vibrations.

There are a couple of foam mats nailed to the walls and so on but apart from that pretty much no acoustic treatment at all. Does anyone have any ideas for what would be the best way to remedy this, and ideally for not much money?

Any advice greatly appreciated. Thanks!

[garethox]

[quote name='maxrossell' post='682146' date='Dec 12 2009, 01:31 PM']My rehearsal room is basically a brick box with pretty high brick ceilings, so the sound tends to bounce around a lot, making everything sound quite undefined and a lot louder than it actually is. We get a lot of unpleasant high midrange, but the floor is wooden boards with a bit of thin carpet so we lose a lot of the bass end punch and warmth to unsympathetic vibrations.

There are a couple of foam mats nailed to the walls and so on but apart from that pretty much no acoustic treatment at all. Does anyone have any ideas for what would be the best way to remedy this, and ideally for not much money?

Any advice greatly appreciated. Thanks![/quote]

The old tried and trusted - egg boxes and old carpet!!!!

[EBS_freak]

Old duvets?

[BigRedX]

You should probably ask this question on the [url="http://www.soundonsound.com/forum"]Sound On Sound Forum[/url].

As well as looking at damping (duvets are good as has been mentioned, egg boxes are best kept for carrying eggs in), you should also check the dimensions of the room (including the height). Distances that are close to equal or fractions of each other will be a problem as they will accentuate some frequencies and cancel out others - this could well be the source of your mid-range hump.

[maxrossell]

[quote name='BigRedX' post='682874' date='Dec 13 2009, 11:20 AM']You should probably ask this question on the [url="http://www.soundonsound.com/forum"]Sound On Sound Forum[/url].

As well as looking at damping (duvets are good as has been mentioned, egg boxes are best kept for carrying eggs in), you should also check the dimensions of the room (including the height). Distances that are close to equal or fractions of each other will be a problem as they will accentuate some frequencies and cancel out others - this could well be the source of your mid-range hump.[/quote]

Yeah, I figured that might be the case. The room is square and the walls are almost exactly twice as wide as they are high.

I was thinking I might try experimenting with hanging offcuts of carpet about one or two inches away from the walls, full-height, just to see if I can trap some of the unwanted reflections, and then work back from there. I also think we need some thicker carpets on the floors.

[BigRedX]

Sounds like a complete nightmare.

I'd start by looking for somewhere else to rehearse, but if the other advantages of the place outweigh the acoustical issues, then you're going to have to look at building some serious bass traps and diffusers. It might be worth looking at making a false wall down two sides of the room by pulling one of the corners in by a foot or so. This will stop the room being a cube and remove the parallel reflective surfaces.

Be careful with simply adding lots of damping without any real acoustic treatment thought, as you need a certain amount of reflective surfaces to be able to hear all the sounds, the reflections just need to be controlled. A very acoustically dead room will just have you playing louder to compensate for the damping - and still won't sound much better.

[maxrossell]

[quote name='BigRedX' post='682937' date='Dec 13 2009, 12:42 PM']Sounds like a complete nightmare.

I'd start by looking for somewhere else to rehearse, but if the other advantages of the place outweigh the acoustical issues, then you're going to have to look at building some serious bass traps and diffusers. It might be worth looking at making a false wall down two sides of the room by pulling one of the corners in by a foot or so. This will stop the room being a cube and remove the parallel reflective surfaces.

Be careful with simply adding lots of damping without any real acoustic treatment thought, as you need a certain amount of reflective surfaces to be able to hear all the sounds, the reflections just need to be controlled. A very acoustically dead room will just have you playing louder to compensate for the damping - and still won't sound much better.[/quote]

I know what you're saying. Unfortunately we're locked into using this space for various reasons that are frankly too boring to go into right now.

Also, due to the nature of our arrangement with the space owners, any changes we make to the space are pretty much limited to hanging stuff on the walls and putting stuff on the floor. I wouldn't seek to attenuate all of the reflections - for instance I have a feeling that the ceilings, which are a series of brick arches, might actually help to provide room ambience in a far more random and therefore pleasing way. I think it's mainly that we need to break up the broad expanses of bare breezeblock that are currently reflecting the hell out of the drums and guitars. I think we might try experimenting with dampened risers for the bass and drums as well, just to get them off our rubbish floor.

[yorick]

Old floor to ceiling heavy weight curtains are good. Check your local charity shops.

[skankdelvar]

The old-fashioned free-standing office partitions? About 5' high. Usually came in blue or khaki hessian. Available from seedy recon office furniture shops run by odd people called 'Mad Barry'. Or, better still, your local tip.

Stand a few of those around the edges, round the amps, etc, see what happens. Glue some rock wool to them? Might break up some of the reflections.

[Balcro]

[quote name='maxrossell' post='682941' date='Dec 13 2009, 12:48 PM']I know what you're saying. Unfortunately we're locked into using this space for various reasons that are frankly too boring to go into right now.

Also, due to the nature of our arrangement with the space owners, any changes we make to the space are pretty much limited to hanging stuff on the walls and putting stuff on the floor. I wouldn't seek to attenuate all of the reflections - for instance I have a feeling that the ceilings, which are a series of brick arches, might actually help to provide room ambience in a far more random and therefore pleasing way. I think it's mainly that we need to break up the broad expanses of bare breezeblock that are currently reflecting the hell out of the drums and guitars. I think we might try experimenting with dampened risers for the bass and drums as well, just to get them off our rubbish floor.[/quote]

I would try getting hold of some 8x4' sheets of 12 / 15mm fibreboard and rest them against the walls. If the building owner will allow, I would suggest you just use 1 screw for each at the top to prevent them falling forward. Place them so as to fill up the wall spaces between (and or overlay) the foam mats.

Balcro.

Edited December 16, 2009 by Balcro