soundproofing, my situation

[jimminy]

Just a quick question I hope will be simple.

I want to isolate myself from my neighbors and for my neighbors.

I have 2 walls in a rectangular room, in an "L" shaped relationship, that open onto the common area of my condo building, and the other two walls onto my own space which I'm not worried about leaking into.

These first two walls though have no resistance to sound. I can turn on the stereo in this room and hear it with clarity on the other side. They are typical wood framed with gyp bd (drywall)both sides. One has a door, and the other has a window, strangely because the other side is inside the building. I plan to frame over this window (I can't just remove it because its also part of the common area), then install resilient channels onto both walls, and gyp bd over them, covering them entirely with new gyp bd.

I'm wondering if this is the best solution, taking economics into consideration. It seems to be, because everywhere I look resilient channels seem to cut sound transmission the best on a cost/results basis. Maybe someone here knows better.

But the door is a problem. I want use it, so covering it entirely won't work. What's the best thing, just hang a heavy curtain over it? I guess I'll do the resilient channel/gyp bd thing over the door panel itself, I'm just worried about leaking around the edges. Maybe it won't be too bad, I'm allowed to make a little noise.

I just want to be able to monitor, using headphones all the time is killing my ears and the mix sucks.

Thanks in advance.

 

[knightfly]

Here's a thread re: window plugs

http://www.homerecording.com/bbs/showthread.php?s=&threadid=56727&highlight=window

As far as doors, is yours hollow core or solid? Swing IN or OUT? Is there room for a deeper frame and a second door?

If the door swings IN, there will be stops on the OUTSIDE of the door, to limit travel. In order to seal around the door better, you'd need to remove these and use something like foam weatherstrip which would be partially crushed by the door when closing - there are door threshholds that drop automatically to seal the bottom, otherwise you'd have to step over a bottom seal piece - without one of these, it's nearly impossible to seal the bottom of the door.

If the door is hollow core, replace it with a solid core door. An exterior Stanley pre-hung with full weatherseal does a pretty good job of sound reduction - again, the bottom is the hardest part to seal.

If you have the room and budget, placing an extra layer of gyp board over the existing wall and caulking tight would help some - ANYTHING that adds another air space is reportedly LESS effective than removing the existing gypboard, adding Resilient Channel, and putting two or three layers of gyp board over the RC -

Another approach would be to have a second wall built inside the existing one, including a second door - this is usually done with metal studs and two layers of gyp board (seams staggered) with fiberglas insulation between the studs, and gyp board ONLY on the side toward the open room. The more air space you can allow between existing wall and new wall, the better - 2" is about minimum, 3 feet better :=)

Generalities - MASS is your friend, as is silicone or butyl caulk (non-hardening kind in both cases) - your goal is to make whatever construction you use, airtight enough to not sink if it were a boat.

For just keeping from irritating your neightbors, it shouldn't take a lot - the ideal Sound Pressure Level for good mixes is around 85 dB, C weighted - louder, and you risk permanent ear damage, softer and you'll tend to make bass-heavy mixes.

If you have any more details about your existing construction, come on back and let's discuss them... Steve

 

[jimminy]

knightfly, thanks for taking the time.

I'm doing this project more to keep from annoying the neighbors than to keep all the sound out when I'm recording, and as long as there isn't enough sound getting out to piss people off, I'm good. I'm going to try just putting the plug in the window(thanks for the link), putting up the RC over the existing gyp bd, and adding a layer of gyp to that, and see how it works. I guess I can alway add a layer of gyp again, probably cheaper and less hassle than tearing out the existing gyp bd.

Luckily, the door is solid core. I think I've decided to basically leave it as is, putting a layer of gyp over it over RC, use weather stripping where I can, and then hang a carpet or thick curtain in front of it to dampen the sound that will inevitably 'leak' at the seams.

I'm lucky, because I'm on the first floor over parking, with a concrete waffle slab deck. So no noise at the floor. The ceiling may be a problem, but I'm gonna play it by ear. If there are complaints, I'll do something, if not, great.

The other thing is the outlets and switches. I'm going to try to do it without moving them by adding a frame of gyp around them over the existing gyp, then when I have the channel installed, the new gyp will sit right on top of the channel and the little gyp bd frames, creating a recess in which the switches and outlets will be. This will effectively create a hard bridge between the new gyp layer and the old layer, so I'm thinking I might install these frames using silicone to adhere themm maybe this will somewhat decrease the bridge.

I know this won't do anything for sound transmission at the these locations, but here again, if it seems this is a bigger leaker of sound than I anticipate, I'll do something else later. I wonder if anyone makes switch covers with STC rating.

Anything you might add is greatly appreciated, otherwise I'll let you know what happens. The next big job will be to make the room sound good. oh boy...

 

[knightfly]

"The next big job will be to make the room sound good. oh boy..." - Check these guys out, I've downloaded the demo and gonna order the complete setup in the next 6 months - be sure to click on "demo room" and read the whole thing, for a good start on room sounds -

http://www.etfacoustic.com/

Also, if you don't already have one, go to Radio Shack and buy one of their Analog Sound Pressure Level Meters - about $40 or so and well worth it. Your ear constantly adjusts to the current SPL as being "normal", up to the point where blood comes out and messes up your new shirt - the only way to mix at a constant level so the Fletcher-Munson effect doesn't screw you, is to use an SPL meter and maintain an average of 85-90 dB SPL, measured with "C" weighting.

I keep mine on all the time I'm mixing, and when I make a change I re-check the level in the room so I'm staying at constant 85 dB - this is, coincidentally, the max OSHA recommends for 8 hour exposure AND, the best balance of freq response for the human ear...

The good news is, it ain't all that loud and shouldn't take too much to keep your neighbors away from the hot tar and stinky chicken feathers... Steve