Acoustic treatments

[cam]

Hey guys, I know dick about room treatments. Could I make some home made panels about 2ft x 4ft from plywood covered in foam and then covered by some material that the wife will ok. If I grabbed a 4ft x 8ft piece of plywood and made 4 panels, where would I put them for the best effect. I am not about to pay big bucks for name brand, I would rather make them myself. Any knowledge would be appreciated.

[Dusty Chalk]

Yes, you certainly could make DIY panels. But what is it you are trying to accomplish? What is it you think is wrong with your room? What you are doing sounds like the beginnings of something, rather than the entirety of something.

Try googling "Ethan Winer". He's a freak about treating room for bass over anything else, but would certainly give you good advice.

[cam]

Thanks DC, I found alot of good stuff.

[topspeed]

Here's a great primer for room acoustics:

http://www.acoustics101.com/

Naturally, they are going to be pimping Auralex products, but as an owner of some of their stuff, you could certainly do worse. Good quality at a fair price.

I'd also suggest PM'ing Kexo and SirT. Kex built most of his treatments and SirT is a sound engineer well schooled in room treatments. Although he left the site, I'd be surprised if he didn't check his e-mail as well.

Hope this helps.

[Woochifer]

The cheapest way to go is to simply grab a box of acoustic ceiling panels and line them up behind your main speakers. Those drop ceiling panels cost less than $20 for a box of eight panels at Lowes. I use them in my setup, and they audibly reduce the reverberation in the room and help to tighten up the imaging coherency. They are effective at absorbing in the midrange, and less so with the highs and lows.

It was also ridiculously easy to make these panels look halfway presentable (you can see them in my gallery pics). I simply took the ceiling panels, and wrapped them in cotton fabric tacked down using a hot glue gun. To frame them and make them easier to handle, I used wood strips along the top edge and clamped the wood to the panel using 2" C-clamps. To suspend the panels, I simply threaded fishing line through the C-clamps and suspended them from a picture molding. I could just as easily have screwed a hook into the wood strip and mount them onto the wall that way.

I'll admit that the acoustic panels worked noticeably better when I just lined up six of them behind the speakers to create a "dead zone" up front. But, my wife would not have any of that, so after I dressed the panels up, I was limited to only three up front.

If you want something that more consistently absorbs throughout the frequency range, try Owens Corning rigid fiberboards. They go for about $80 a box (eight panels per box) and most stores require that you special order them. Their absorption rating is higher than the acoustic ceiling panels, and it doesn't vary as much between the highs and the mids. Someday, I'll try these out in my room.

Here are a couple of great article on room treatments that also include some links to commercially available products.

http://www.hometheaterhifi.com/volume_11_4/feature-article-acoustic-treatment-methods-and-materials-12-2004-part-1.html
http://www.hometheaterhifi.com/volume_11_3/feature-secrets-lab-room-treatment-9-2004-part-1.html

[cam]

The cheapest way to go is to simply grab a box of acoustic ceiling panels and line them up behind your main speakers. Those drop ceiling panels cost less than $20 for a box of eight panels at Lowes. I use them in my setup, and they audibly reduce the reverberation in the room and help to tighten up the imaging coherency. They are effective at absorbing in the midrange, and less so with the highs and lows.

It was also ridiculously easy to make these panels look halfway presentable (you can see them in my gallery pics). I simply took the ceiling panels, and wrapped them in cotton fabric tacked down using a hot glue gun. To frame them and make them easier to handle, I used wood strips along the top edge and clamped the wood to the panel using 2" C-clamps. To suspend the panels, I simply threaded fishing line through the C-clamps and suspended them from a picture molding. I could just as easily have screwed a hook into the wood strip and mount them onto the wall that way.

I'll admit that the acoustic panels worked noticeably better when I just lined up six of them behind the speakers to create a "dead zone" up front. But, my wife would not have any of that, so after I dressed the panels up, I was limited to only three up front.

If you want something that more consistently absorbs throughout the frequency range, try Owens Corning rigid fiberboards. They go for about $80 a box (eight panels per box) and most stores require that you special order them. Their absorption rating is higher than the acoustic ceiling panels, and it doesn't vary as much between the highs and the mids. Someday, I'll try these out in my room.

Here are a couple of great article on room treatments that also include some links to commercially available products.

http://www.hometheaterhifi.com/volume_11_4/feature-article-acoustic-treatment-methods-and-materials-12-2004-part-1.html
http://www.hometheaterhifi.com/volume_11_3/feature-secrets-lab-room-treatment-9-2004-part-1.html
Hey Wooch, did you find that treating behind your main speakers was or is more important then treating the side walls. And also, should I consider treating my back wall or should I keep that as lively as possible for my surround sound effects.

[Woochifer]

Hey Wooch, did you find that treating behind your main speakers was or is more important then treating the side walls. And also, should I consider treating my back wall or should I keep that as lively as possible for my surround sound effects.

That would depend on your room setup.

In my case, deadening the front wall was important because I use the narrow side of my room and can only spare about 1' behind the speakers. Because the speakers are so close to the front wall, the reflected sound can distort the imaging coherency and make the sound seem harsh if I don't use any absorption up front.

The left main speaker is a lot more than 5' away from the side wall, so the sound reflections coming off that wall do not smear the coherency as much as they would if they were less than 5' away. On the right side, I hung a quilt for both decoration and absorption at the first reflection point from the seated position.

For the back wall, you can use either absorption or diffusion. Terrence used to recommend diffusion for the side and back walls, and the ceiling as well if feasible. Fortunately, a bookcase (filled with books of differing sizes) can effectively function as a diffusor. Otherwise, there are commercial products available.

Aside from that, a thick rug (highly recommended) and cushy furniture will also help. The degree to which you need to deaden your room depends on the room itself. If you can clap your hands and hear a lot of slap echo, then you'll need absorption. Other rooms, for example houses built in the 60s and 70s that came with those acoustic ceilings, might function well as is and any effort to deaden the reflected sound might actually drain the life out of the music. Lot of approaches you can try, and it's actually a fun process experimenting with room treatments.