I'm going to be building a new home studio. The room will be about 25'x20' with 7 ft. ceiling. I wish the ceiling was higher. Will a 7 ft. ceiling be a problem? Should I put diffusion on the ceiling?
I've already built bass traps with mineral wool and also have some acoustic cotton so I think I can treat the room pretty well to make it sound good. I would like to make it sound proof from outside noise. What is the best way to do this?

I was thinking of making all the stud walls have insulation between all the studs as well as sheets of styro foam nailed to the studs behind the drywall. Would this make the room pretty soundproof from outside noise? Would it hurt any of the room acoustics inside the room?

Also, is drywall best for the walls or would a wooden panelling make for a better sounding room?

Forget the drywall - it's worthless.

The only ways to isolate from the outside are:

- Isolate the structure. Consider building staggered stud walls so the inside and outside dryall isn't on the same stud. Use a 2x6 bottom and top plate and alternate 2x4 studs on each side. Fill with insulation and you're good to go.

- Mass, mass, mass. Use more than one layer of drywall. While this will reduce the amount of bottom end absorbtion that you can expect from the drywall structure and require additional bottom end control inside the room, it's a very cheap way to get isolation. Plus, if you do the staggered stud thing too, you'll gain back a little of the flexibility in the wall.

Bryan

Hey bpape, I think you meant to say forget the styrofoam, right???

I agree that what you are describing will not provide much in the way of "soundproofing" which requires very specific construction techniques and LOTS of mass (as bpape states).

However, many of us don't have the budget for this type of construction, and there are ways to improve the situation.

What I would do is get a bunch of drywall, cut it into 16" strips, and install at least 3 layers between the ceiling/floor joists over your head. Then stuff the remaining space with rockwool or acoustic cotton or fiberglass, and cover your ceiling with cloth. That will improve your isolation situation dramatically, though it still won't provide complete iso.

If you have the budget/carpentry skills to build the room-within-room construction, then do that. You might want to check out Rod Gervais' book....

Yes - thanks. Not sure why I typed that. I meant skip the styrofoam.

While the drywall between the joists will help a little bit, the majority of the noise is going to come through the structure.

The reason I suggested the staggered stud construction is that it is relativley easy and cost effective in relation to a true room in a room. Figure an extra 15% or so for the plates and an double the stud cost for the walls. In a normal sized room, that whole thing would be less than an additional $200.

Also, plan on caulking EVERYTHING. Build MDF boxes around all your outlet boxes and caulk the cable entries, caulk all drywall joints including the floor, put in some door seals, etc.

Bryan

Wow. Is it a bad idea to use the metal studs instead of wood in order to save a little?
Also, I'm thinking of using a real wood paneling instead of drywall since I'll be recording a lot of acoustic guitar in the studio and I've heard that wood makes for a better sounding room. Any thoughts on this?
If I just double up the drywall or use one sheet of drywall and one sheet of wood paneling and put a lot of insulation between the studs, will that do the job? The wood panelling is about the same thickness as drywall, I think.

It all depends on how much isolation and at what frequencies you need. Wood paneling won't have anywhere near the mass as drywall so it wont' be as good at lower frequencies.

Steel studs can work fine.

Bryan

Since the room will be in the basement and only have 7 ft. ceilings what is the best means of making the ceiling soundproof? Just double up the drywall on the ceiling? Also, will overhead lighting allow sound through the ceiling?
I'll have 3 cats upstairs when I'm recording and they're pretty quiet but if they jump around a little while I'm recording it will make noise. Thanks a million for all of your help, guys.

Will 7 ft. ceilings be to low to have good sound for recording acoustic guitar and bass? I think the room will at least be 20x20x7 and maybe even bigger. Will ceilings only 7 ft. tall create any problems?
Is drop ceiling a bad idea or will it work ok if I put insulation above the drop ceiling?

A drop ceiling will not only lose height but will also kill any isolation hope you have. Fill the cavity in the ceiling with insulation and treat portions of the ceiling with absorbtion and use a harder floor.

Bryan

What do you mean by a harder floor? Are you saying to use drywall for the ceiling and not drop ceiling?

You said you wanted isolation from outside - a drop ceiling won't do that. You need an insulated cavity and lots of mass - that means drywall.

The floor can be a harder surface like hardwood or laminate and then put up a couple of clouds/reflection panels on the ceiling.

Bryan

The floor will be cement because it will be in the basement. I may put down laminant wood flooring or just paint the cement or maybe lenolium. So I should make the ceiling drywall and two layers thick like the walls?
What are the clouds or reflection panels on the ceiling? Are you talking about some diffusors or some acoustic foam? Thanks for answering my questions.

If you want isolation then the ceiling has to have some mass to it so drywall is the cheapest way to do that. But don't forget to insulate the cavity above fully. Basically just like the walls.

On the ceiling with a concrete floor, you'll want some good absorbtion on the ceiling. Diffusion isn't going to get it and most acoustic foam is crap. Get somthing that uses OC703 or mineral wool as a core. I'd use a minimum of 2" thickness spaced 2" off the ceiling - 4" is better but you just don't have the height and can make up the bass absorbtion elsewhere in the room.

Bryan

Would it help if I put down laminated wood flooring like purgo or something like that?

Help acoustically? Probably not. Most reflecting surfaces sound more or less the same.

--Ethan

3Dfan,
I dunno if you're still working on this or not, but for sound isolation you might want to look into Resilient Channel. I have this stuff in my room and it works pretty well. I also would suggest building a floating floor to keep those low frequencies from vibrating to the outside.

Just my $.02

B