Acoustical Foam

Curious whether others have experimented with acoustical foam. I ordered 1.75" foam tiles and foam corner kits. I have installed them tonight in the room that I'm preparing. There is no equipment in that room yet. I have 1/2 the foam tiles up on the walls. I will not be putting any on the ceiling as my wife has already commented that this is insane looking as is. I have been testing the acoustics by clapping my hands in the room before, during, and after the foam has been installed. So far, it has definately lowered resonances / echo, however, the room is not dead like a recording studio. Perhaps, once all the foam is up, an area rug is down over the wood floor, and there is equipment in the room, the room may be more dead sounding. That is certainly my hope. If it works, I will post more about exactly what I bought, the cost of the tweak, and my feedback on the cost/benefit of this change. Alot of the systems that incorporate acoustical treatments have big budgets for panels and other expensive room treatments, so my tweaks are certainly more budge oriented than aesthetically pleasing. I just purchased my first home, so my housing costs have nearly tripled. There definately is not as much money to play with these days, so I definately won't be purchasing expensive equipment as upgrades. That is why I'm trying to find tweaks that can have the sonic benefits of upgraded equipment at a much lower cost.
You are headed down the wrong path. A stereo system in a room that is "dead like a recording studio" sounds like crap.

Check this out.
Where did you purchase the aucoustical foam panels?


I don't think the room will be dead sounding. I worked at 2 radio stations in my younger days, and the recording studios that were dead sounding had heavy steel doors and purpose built walls that could withstand artillery fire. This room is not that solid in construction, so it won't be completely dead and I'm not treating the ceiling so that will still provide some reflection. I bought the following:

Worst case scenario is that I don't like the foam, and I tear it down wasting about $300 that I spent.

If you check out my virtual system you can see how the new GIK Tri-traps integrate into a room in an aesthetic way. These use heavy mineral wool and are broadband absorbers (effective down to 100Hz with a tiny little bit of absorption even at 50 Hz).

As long as you have something broadly absorptive and with a density of 3 pounds per cubic foot or more (foam, fibreglass, mineral wool) then you can get some nice results with decent coverage. I believe that controlling rear wall (behind your listening position) reverberation is the most important use of these products.

As others have stated above a reflective room is pleasant and a dead room is dull and lifeless....which suggests that one should avoid heavy acoustic treatement in front of the listener.

Behind the listener is another matter.....anything reflecting from behind you is likely to interfere with your enjoyment, hiding detail and crowding the sound field in a claustrophobic manner. You will notice I use a combination of dedicated professional acoustic treatments, bookshelves, furniture and a massive stacked log fireplace...all designed to broadly absorb and improve the reverberation decay times. Long reverberation times are reduced dramatically whilst secondary reflections from side walls and ceiling still give a lively feel to the music. Dead sound is NOT the goal (in fact the early reflections help bring out more detail in music.....long reverberations are, however, a nusiance)
First-reflection points (side, ceiling, floor) need first attention and, then, depending on the room, system and furniture, you may need additional treatment. However, what is almost always needed is broadband bass trapping and foam tiles will do NOTHING for that.

You should look at sites like for links to reliable recommendations.


BTW - 4" tiles are no good for broadband need greater thickness.... a minimum of 8" with foam - the most effective treatment location being the corners. Tiles may actually be counterproductive as you attenuate the upper mids and make the lower mid & bass relatively worse...i.e both a dead and a boomy room.....YUK.
one can't generalize about sonic preferences. a dull room with attenuation in the treble may be preferred by some and not by others.

this issue has nothing to do with accuracy or "hi fidelity".

it is all about achieving one's sonic objectives, whatever they are.

i use foam on the side walls and behind the listening position, a room tune in the center between the speakers and a room tune in the corner.

i tune the room to create the "sound" i enjoy. it's all about experimentation. it doesn't hurt to use a spectral analyzer at the listening position.
Interesting responses full of great information. I have put the foam on the walls immediately flanking and the wall behind my speakers and equipment. I have not treated the back wall where my chair will be located. From what I've read in this post, that is the opposite of what should be done, but at this point, I'm going to foam all the walls and then reverse tweak the room by removing foam until the desired goal is reached. For low frequency control, I have positioned 24"X10"X10" wedge shaped foam which joins at the junction of the ceiling and the walls. It is probably 6" thick at its greatest depth. I'm moving my equipment over tomorrow with the exception of my amp, speakers, and sub which are too bulky and heavy to move in our cars. I'm disassembling my MapleShade rack tonight. It weighs rougly 200 pounds assembled and is great to look at but is difficult to take apart and move when required. I will follow-up to this post once everything is going in that room. It is an experiment I'm looking forward to sharing here as the observations may be useful to someone else venturing down the path of room treatments which may not be as well understood as some more well known topics such as the differences between cd and vinly or the pros and cons of tube vs solid state amplification.
Hi Firecracker, congratulations on your new set up and yes do keep us posted on the progress !

I myself is also planning on adding foam panels to my setup, both behind the speakers but more importantly behind my listening position... my room is not ideal such that my seat is right against the back wall... it's bad but there's no way my wife will allow me to change that.... so question is will cover the back wall all by these foam wedges help? From Shadorne's it sounds like this is the way to go but would like to hear more folk's experience here. thanks.
Hey Chuttt,

I have approximately 2/3 of the walls covered now. I'm working from the front back to my chair. The room is getting a little less resonant now. However, I tested the higher mid frequency by whistling in the room the last time I was in there. It's not dull and muted sounding, but that's not obviously the range of frequencies as would be a cymbal crash. I will know the results of this experiment by Sunday, as I'm going to finish the room and set-up my gear. My parents and wife thought the room looked bizarre, but now that the walls are covered more evenly, I'm starting to like the way it looks. For a seamless look, I would recommend having the manufacture ship all pieces from the same production run to you. I rec'd mine in two shipments, and the pieces don't line up perfectly between the two orders even with the same product.
I've been using carpet pad behind curtains. It's cheap and even more dense. And the more layers you put on the lower the frequences it will catch. I only put it on one wall though for now. Makes a huge improvement though. And with the curtains you dont see it at all. You might try putting some carpet pad under the foam for even more effectiveness. That horse hair carpet pad would probably be the ultimate. But that stuff can get expepensive (not foam based at all). That's the most expensive kind out there I believe. I'd like to try that though.

Anyway just experiment. If it's a small room sometimes you have no choice but to make it almost dead. Which is fine because any speaker will be able to fill a small room and what ever comes out of your system is enough to make it lively. Just make sure you can catch those lower notes or it will be boomy and worse!

But what I've found to sound the best so far is to totally cover a wall or two. And then on the other walls use a lot of diffusion instead. Break up the soundwaves with varied hard surfaces. Right now I'm using some woven mats and a wooden screen ( that uses checkered board cross patterned wood pieces) on the side walls. Works extremely well for breaking up the sound waves (especially right next to the speakers to keep it from reflecting off the side wall) and letting the soundstage come out.
My stereo has been powered up for a few days. I like the overall effect of the foam. I think that there is still sparkle in the treble. I'm not sure if I have lost much treble (probably have though based on the posts above), but I'm not unhappy with the results. I have posted pictures on my virtual system. For now, the foam stays. The room is 10 X 12, and I don't think it would sound very good without the treatment.