Soundproofing Raw space

[gullfo]

creating a number of adjacent rooms framed with ceilings supported on the freestanding walls (use isolation sway braces and/or sheathing on corners) and with 3x 5/8" type X drywall all around should give a decent level of isolation between rooms. then you need the hard stuff - air. if you can run some duct overhead and drop a flex into a baffle box on top of the room, you can provide air and cooling/heating as needed. 2 ducts - supply and return needed. if you can swing an electric damper @ the duct drop on each room to allow each to have it's own thermostat, that would be nice.
the concrete floor should be ok. put drums and amps on decoupled membrane platforms to reduce impact and vibration going directly into the floor.
seal up the rooms. one option is to put in some windows between a couple of rooms so you can use them for recording if desired.
for treatment - you could angle the room walls and ceiling to reduce flutter, or scatter absorption or panels (more rugged) to reduce reflections. polys are a good choice for LF trapping as well as diffusion.
i'd skip the overpriced drywall and the green glue in this application.

[ionskyon]

Thanks for the response Glenn,

Very helpful. Using 5/8 rock and framing with 2x's was what I was hoping to hear. hahaha.

As far as insulating the stud bays I'm leaning towards blowing in cellulose myself and foregoing duroc, wonderboard or batting. I read that 4" of cellulose with rock can give you a STC rating of 50 (Also has a decent R value). Any thoughts on that?



Just looking around online I'm finding caveats stating improper construction of decoupling platforms (which I haven't heard of before now) can result in magnifying low freq sounds, Do you know of a correct building methodology?


Forgive my ignorance, but when you say polys are a good choice for LF trapping as well as diffusion, what do you mean by poly's?

And yeah, air exchange is definitely something I've been considering and the drop ceiling seems like a good idea. Would you suggest any different treatment on the ceiling than in the walls?

Thanks again!

Ian

[gullfo]

the blown insulation can settle and become dense whereas the soft insulation batts tend to stay in place and provide the desired damping and air flow. on the decoupled membrane flooring - instead of making the entire floor in the unit - you make smaller platforms - soft carpet pad, semi-rigid insulation etc under 2 layers of plywood. finish with some carpet (under amps for e.g.) or another layer of 29/32" ply for screwing in drum kit hardware and can be replaced.
poly-cylindrical = polys -- set up 2 vertical 2x2 screw to the wall then bend in a 1/8" plywood sheet. behind the sheet you want soft insulation to dampen the air cavity and the sheet. you can standup insulation batts with twine then put in the panel.

[ionskyon]

Thanks again,
I was looking at wet blown cellulose but talking to a contractor I know he said the same thing as you.
Thinking of a staggered wall with roxol.
what about sound leaking thru the ducts?

[Rod Gervais]

The best "bang for the buck" is standard fluffy fiberglass - which has a slight advantage in LF isolation over more dense products. Mid and high frequencies are never the issue.

Rod