Studio design for Audio

[Ty Ford]

Hello Craig,

Thanks for noticing. there are two parts of good acoustic design, exterior noise abatement and interior acoustic design. Exterior noise abatement is about keeping outside noise out. The physics for that involves DID – Density, Isolation, Density. You need at least two walls separated by as much isolation as possible. The home I bought 22 years ago had that. It’s a brick rancher.

My studio is in the basement and the basement is 3/4 below ground. Lots of dirt to stop the exterior noise from hitting the foundation walls. Someone flushes the toilet or the trash truck comes by and I have to wait. Fortunately, those sorts of things don’t happen very often.

The room is 25′ x 35′. I don’t have a booth. The entire room is my booth. This allows a large space for the sound to travel. In doing so, it runs out of energy, Inside I use both diffusion and absorption to control reflections.

Think of sound as a moving visible force, like a pool ball on a pool table. Throw the ball down the table and it will continue to roll, bouncing off the bumpers until it runs out of energy. Sound is similar. It continues to reflect until it runs out of energy. Your job is to be able to hear the reflections and put up stuff to either absorb or diffuse as needed. With a pool table you only have two dimensions, length and width. With sound you have three dimensions, floor, ceiling and walls. Too much absorption and the room can sound spongey, especially if the room is very small or you’re very loud. In essence, you excite the foam and can hear it vibrate. Diffusion helps there by breaking up the sound waves into smaller, less energetic waves that can then be better absorbed.

I do consultations with clients in which they send me sound files recorded at their site. This is helpful because if your room is ringing or has other problems, you can’t always hear it during playback because the room is also ringing and exhibiting other problems during playback.

[Craig Alan]

Thanks for help Ty. (I didn’t see your post till I got on CCow to see what everyone thought of the new iMac OS). My plan is to have a studio built by a company that builds log cabin houses. It will allow for a lot of different shots for film and photography. Is this doable for sound control? I though if I asked them to have two walls on the outside walls it would help a lot. And Acoustic Panels in the studio area inside. On the outside double walls, what material would you recommend to fill the gap? And what Acoustic Panels would you recommend? Also will windows be a problem? Would the right drapes help sound as well? They can double as backdrops.

I use Hyper Cardioid Microphones mounted on boom poles over head on a lot of shots. They are pretty sensitive so they do pick up whatever is around but also very directional. Perhaps the ceiling and roof will be a factor as well. If I have it built with some thought to sound I will defiantly consider a consultation if there are problems.

[Ty Ford]

Hi Craig,

When you say outside walls, do you mean the inside of outside walls or actually outside of the cabin?
Corning 703 panels are always good choices. I also use 4″ thick foam panels – 2′ x 4′ in various locations on the walls and 1″ Sonex panels on my ceiling to absorb ceiling bounce. What’s on your floor?

Regards,

Ty Ford

Cow Audio Forum Leader

[Craig Alan]

Hi Ty,

I meant what do I use between the double walls?

And what does the ceiling/roof need between them?

The studio where I work picks up the sound through the roof

including airplanes and helicopters. Its hard to tell sometimes where sound is coming from, but I used a long boom and headphones and got my microphones as close to all the walls and ceiling as I could and that’s where the sound was coming from. But I don’t own that studio and all I can do is suggest things.

I want to design mine as well as I can afford. I’d rather have less space and better sound than vice versa.

I looked up corning 703. Lots of different 703 panel versions. Does it mater – will any of them do the trick? The most expensive is “sound proof” (I think that’s a 704).

Thanks for your help.

Craig

[Ty Ford]

You need to be sure your double walls are not touching in any way. There are acoustical products that can help to make this happen, but having a good acoustic design engineer can help a lot. If you build the walls properly and they are not in contact with each other, air works. But if you’re hearing planes now, you might me in an airport flight zone and there’s not a lot you can do with a location like that even if you build a room within a room.

[Craig Alan]

Hi Ty

The wall design is for what I plan to build. The planes problem are at an already built studio.

So a double wall that does not touch each other works using air between them? I thought people used sand or other higher end material to go between the two walls???

For inside a studio, does any of the corning 703s/704s work better than the others or is it just different sizes and number of panels in the package. They have a lot of different ones on their site.

[Ty Ford]

If you’re in a flight plan, you may as well give up. Seriously.
The acronym I use is DID – Density Isolation Density. That’s TOTAL Isolation. NO PARTS of one wall touching the other including ceilings and floors. Not even nails.
If you put a line of cinder block between the walls, you’ll increase the Density. So you have DIDID. Provided those parts DO NOT TOUCH. You get better sound proofing from outside noise. It will NOT help you with airplane noise.
Again, if you have plane noise coming in through the roof, you’re screwed. Sorry.?