Foam bass traps

[Mark6432]

Are foam bass traps, such as these

Foam bass traps - http://www.acoustic-foam.co.uk/products/AFBT02-Acoustic-Foam-Bass-Trap-Box -of-2-Bass-Traps.html

any good?

I'd being using them in a 6x7ft room along with DIY broadband absorbers and hi freq acoustic tiles.

[Daniel Davis]

There is nothing wrong with foam as a sound absorbing material, but the traps on that site are not physically large enough to absorb low frequencies. They will contribute to some absorption or the low-mids, which can be helpful, but won't fix your modal issues.

1ft trap
longest dimention of thickness is 334mm
1/4 wavelength of 250Hz

To be honest what you probably need is something that deals with all the frequencies below 250Hz rather than the ones above it.

Now a 2ft trap which some companies do will go down to around 125Hz which is more useful, and a 1m trap down to 85Hz, now you're talking.

[Mark6432]

Hi Daniel,

Thanks for the advice, some good succinct info.

If I was staying in the room long term (probably moving into garage in the summer) I'd build some of those super chunk corner traps, not sure how to DIY them as non-fixed units. Would a pair of the foam traps stacked (ie tow on each side) make for double the frequency response down at the bottom end? I guess that way I could then add a third lot when I move into the garage....or do I just sort out DIY approach and make some tall ones which I can move? hmmm.decisions, decisions...

[Daniel Davis]

£40 per 2 traps for a few pence of foaming materials. humpf.

That would buy you a lot of rockwool, corning or other slab material.

Another thread recommended Rockwool RW3 Slab which is a UK alternative to Owens Corning.

[Mark6432]

Thanks again Daniel!

I didn't realise you could buy 'slabs' of the stuff, which presumably this is? I guess I can cut this into triangular towers, frame and wrap?

[Martin Walker]

Thanks again Daniel!

I didn't realise you could buy 'slabs' of the stuff, which presumably this is? I guess I can cut this into triangular towers, frame and wrap?

Hi Mark,

Yes, of course you can - this 'superchunk' approach has been used for many years. Here's a DIY image showing the wooden corner frame part-filled with rockwool:



Martin

[sheggs]

You don't have to use the slabs for corners though. Fluffy insulation will work just as well, depth of the material is what is improtant here rather than just density

[Mark6432]

Thanks chaps, you're right about the DIY cost yielding more bang for the buck. I got on and made a pair of superchunks today. Am going to do another pair tomorrow. Sadly my wife's not as enthralled by my new found obsession as I am!

[Martin Walker]

She might change her mind once you cover the fronts in some fabric that tones in well with the rest of the room decor

Martin