Acoustic Foam


can someone please tell me the cheapest place they know of to get 50 mm acoustic foam?

They have it at guitar center but it's $35 for not very much foam. I'm trying to get rid of early reflections. I am buying some bass traps also, but I think I also need acoustic foam.

Since I'm lousy at building things, I'm not building any bass traps or anything even though it'd probly be way cheaper.
I think you can use any foam with open pores. For my former room I bought a lot of pyramid-shaped foam that was originally thought for beds. You don't need a specifically shaped surface anyway. Foam with open pores will always do something on the audio even if it is just flat. The pores do the main job, not the shape. The thickness plays a role, though.

But are you sure that you need foam? It eliminates echoes but it also suppresses middle to high frequencies. With too much foam your room will become dull. You don't see much foam in acoustically good studio rooms, if any. Maybe a piece behind a singer or guitarist but not more.

For general acoustic treatment for middle and higher frequencies you rather need diffusors. This can be almost any kind of not-too-hard material with an irregular surface. Be it foam with closed pores or wood or something else. A diffusor sends the audio in different directions, it scatters the waves.
But are you sure that you need foam? It eliminates echoes but it also suppresses middle to high frequencies.

And is not as good as rockwool for doing this. Rockwool is very cheap, but you need to cover it with hessian or something, so may be too much of a DIY job for the OP.

I think it's very good for elimanting MF and HF reflections if the room needs it, specifically behind, above and/or to the side of your monitoring area.

But don't use it to deaden the room, ideally you want to make it about as ambient as the average room that people listen to music in, ie a living room.

When I moved into my studio it was just four plastered walls, a wooden suspended floor and a high ceiling. So quite echoey. I just put enough HF baffling in to stop me making my mixes too dry (as I would otherwise be compensating in my mixes for all the reverb I was hearing because of the room).

And then, as peter says, you need diffusion. Bookshelves (without glass fronts!), do this very well.
People seem to be telling me not to use foam. This book I'm reading, Mixing Audio: Concepts, Practices and Tools says a 50 mm acoustic foam usually helps suppress early reflections but people on forums seem to be saying otherwise and it's true, in pictures of studios I never see foam on the walls.

Do you think I should just get some bass traps, I mean start with that or what? Also, what is HF baffling?

Thanks for all the help!
Just FYI, I ended up ordering this sound proofing foam from B&H. It's $30 less than the same stuff from Musician's Friend and free shipping. Very cool.

Foam gathers odors, becomes unsightly quick, and is frankly, not a very good choice for audio acoustic reduction. Buy some colorful blankets, hang them < 4" from the walls. Tapestries work great! They are about 30% better than foam!:errr: