simple low-cost sound isolation

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campersand
Posts: 6
Joined: Tue Sep 30, 2003 3:13 am

simple low-cost sound isolation

Post by campersand »

I apologize if this has already been covered somewhere here (it probably has) but all the info I could find was much more complicated and expensive than what I need.

Anyway, I just moved into a duplex and I want to put my "studio" in a room in the basement. By studio, I basically mean an area for me to record and mix mostly guitar, bass, piano, vocals, maybe a little bit of quiet drums. The room has approx 7 1/2' wood ceilings and is about 10x15 with concrete walls and floor. The entryway is about 5 1/2' wide with no door. About 12 from the entryway is a flimsy plywood divider that seperates our basement from the neighbors'.

I don't want to do any drastic permanent construction since I'm renting, or spend over $200. What I want is a room that won't sound completely horrible for mixing and most of all a way to block a good amount of sound at the entryway so I don't drive the neighbors crazy. The neighbors are pretty cool so I don't have to make it totally silent.

Thanks for any advice y'all can give me, and let me know if I need to post any more info.

-Cameron
knightfly
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Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

"I don't want to do any drastic permanent construction since I'm renting, or spend over $200. What I want is a room that won't sound completely horrible for mixing and most of all a way to block a good amount of sound at the entryway so I don't drive the neighbors crazy" -

Cameron, you're asking the equivalent of wanting to swim to Jamaica carrying a truck on your back, but not being allowed any extra flotation devices -

Sound isolation, especially bass, requires hermetic sealing, mass, and money. The money part, for a small amount of isolation, looks like a possibility. It sounds like you might be able to build a heavier replacement for that flimsy plywood divider between the basements - that is going to be the worst sound path from the description.

If that opening doesn't need to be opened, you could put up two layers of 3/4" particle board with a layer of 5/8" gyp board (sheet rock) sandwiched between, seal around it with self-stick foam "camper shell tape", and fasten it around the opening (concrete, I'm assuming) with screws and concrete "anchors", those inserts that spread to grip a hole in concrete when you drive a screw into them -

You didn't mention if this flimsy divider is the entire wall between the areas, or if it's just a door - the above construction would cost about $1 per square foot of coverage, more if you have to build much of a frame... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
campersand
Posts: 6
Joined: Tue Sep 30, 2003 3:13 am

Post by campersand »

Thanks for the suggestions. Let me reiderate that I don't need "professional" grade isolation or acoustics. I don't play very loudly and I don't need the room to sound great, just not horrible. So I think what I'm trying to acheive should be possible for under $200 and without doing major construction.

Something like putting carpet up on the walls and corners would do fine for my purposes, but I'm wondering if there are other tactics that would work better and cost relatively the same. And for the isolation part, I'm thinking I'd just need to have a big something or other that I can cover the entryway with while I'm in there and move when I need to get out, so I'm wondering what my options are in that arena. Like I say, the neighbors are pretty cool so I don't think they'd mind some noise, I just don't want to blast them out.

The flimsy board is about half of the wall, luckily the half on the far end of the basement. As for the construction in the opening, it's the only way to get in and out of the room so I need to have it openable. thanks again for the suggestions and any more you might have, I appreciate it.

-Cameron
-Cameron
DopeMan2K
Posts: 5
Joined: Mon Sep 22, 2003 9:18 am

Post by DopeMan2K »

carpets on the wall or audio blankets check some places like
www.acousticalsolutions.com
knightfly
Senior Member
Posts: 6976
Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

Actually, we tend not to recommend places like that here - you can do better with less money using different materials.

For one thing, you've already got concrete walls, which being rigid do NOT absorb any bass, so the room will tend to be bass-heavy without adding lots of bass traps. Then, you propose to put carpet up - all carpet does is to absorb high frequencies - so now, you have too much bass because of concrete walls, and then you put up carpet to kill the highs. The only thing left to do to comletely fuck up your sound is to record it onto bargain cassette tapes at 20 dB too hot a level, then leave the cassette in the sun inside a hot car for a week...

OK, venting over now - had a totally worthless, absulutely fucked day and then somebody made the mistake of mentioning carpet, sorry...

I'm still not clear on what's where in your basement - are you saying that the flimsy wall between the basement and the neighbors basement needs to be openable?

If possible, some sort of drawing would really help here - even just something in Paint, so we can get an idea of what's where. It would also help if you could give more of a description of "flimsy" - are we talking 2x2's with cardboard over them, or what? I'd hate to send you off in the wrong direction just from ignorance... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
campersand
Posts: 6
Joined: Tue Sep 30, 2003 3:13 am

Post by campersand »

carpets on the wall or audio blankets check some places like
www.acousticalsolutions.com


thanks for the link dopeman.

Cameron, you're asking the equivalent of wanting to swim to Jamaica carrying a truck on your back, but not being allowed any extra flotation devices -

For one thing, you've already got concrete walls, which being rigid do NOT absorb any bass, so the room will tend to be bass-heavy without adding lots of bass traps. Then, you propose to put carpet up - all carpet does is to absorb high frequencies - so now, you have too much bass because of concrete walls, and then you put up carpet to kill the highs. The only thing left to do to comletely fuck up your sound is to record it onto bargain cassette tapes at 20 dB too hot a level, then leave the cassette in the sun inside a hot car for a week...

Listen guys, I obviously don't have a lot of knowledge about this stuff, that's why I'm posting here. I tried to word my questions in a way that would make that apparent and would communicate that I want something very simple and inexpensive. I was hesitant to post my question here because I knew I would get this kind of response. I do not need to be talked down to or lectured. A simple explanation, sans sarcasm would do just fine.

I really do appreciate the help you're trying to give me but it's hard to deal with continually getting these smartass, condescending responses even when I'm going out of my way to admit that I'm not an expert and that I don't need pro studio-grade solutions.

Anyway, back to the subject: when you said "the opening" I thought you meant the entryway to the room. The divider does not need to be openable. It is actually made from 2x6 boards but does not go all the way down to the floor in some places, like somebody just slapped it up there, so there's some serious holes in the bottom.

Here's a very simple drawing of the basement:
knightfly
Senior Member
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Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

"I was hesitant to post my question here because I knew I would get this kind of response. I do not need to be talked down to or lectured. A simple explanation, sans sarcasm would do just fine."

Cameron, I already apologized in the same post - I probably should have just started over, but I'd already had a day from hell and was behind in answering other posts as well. I'm sorry you took it ALL in the spirit of smart assedness, it was intended more as an attempt to explain the difficulty of what you wanted, given the restrictions you mentioned.

Please keep in mind that we're here on our own time doing this for FREE (what few donations that have actually been recieved are more than eaten just by server costs) and that we may occasionally let our human side prevail when other pressures get out of hand. Once again, I'm sorry - Minus the rage, however, my previous comments are still valid -

Now, if you're still talking to me, I need to know some details about these 2x6's. If they're sturdy enough, you might be able to put up a couple layers of sheet rock (cheap and effective) that seals the holes in the divider. Sound will get through the smallest crack you can imagine, so each layer would need to be caulked with a high grade silicone caulk and all joints filled and taped, with the second layer offset (no coincident seams) - there were no dimensions on your drawing, but if the studio area is 10 x 15 or so, it looks like the flimsy wall is maybe 32 feet or so? If that's the case, it would cost about $100 to put up a double layer of sheet rock if the 2x6's would support it without other framing. The caulking would run probably another $30-40 or so.

If sound getting upstairs into your own unit isn't a big deal, you'd actually be better off NOT putting much of a door between the studio area and the rest of your part of the basement - those concrete walls (as I mentioned earlier) don't flex, and so all the bass you generate in the room STAYS in the room. If you have an opening like that door, letting some of that sound pressure out into the rest of the area should actually HELP your sound inside the studio area. (Actually, even if sound getting upstairs IS a big deal, what's left of your budget won't get you much relief)

One more bit of info that would help in suggesting solutions - I have no idea what part of the world you live in - I got a wake-up call a few weeks ago when recommending drywall to an English poster - seems the stuff is 5 TIMES as expensive there as it is here :cry: Yet another poster from an island area could get bricks for a couple cents each, but plywood was like a weeks wages...

If you were to have any budget left after sealing up the "wimpy wall", (see, I'm a smart ass even when I'm NOT in the talons of evil) I'd try to find some rigid fiberglas insulation locally, cover it with cloth and treat some of your inner walls to improve acoustics.

If you get time and can post a more complete drawing, including dimensions, as well as a general location (we won't come to your house, just a state or city is enough) then we can probably get you going for what you want to do... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
campersand
Posts: 6
Joined: Tue Sep 30, 2003 3:13 am

Post by campersand »

okay, all is forgiven. I do appreciate you taking time to answer my questions.

so... I live in portland, OR. I'm glad you mentioned that the lack of door would actually improve the sound because for some reason I never even thought of that. But the 2x6's are definitely sturdy enough to put some sheetrock around so I'll probably try that. Luckily, about half of that wall is concrete and the other half is the 2x6's, so I'd only have to cover approx 70 square ft.

As for the walls in the studio room, I spent a lot of time looking through the SAE site yesterday and I'm considering doing some 3" or 4" fiberglass board at a slight angle, just as you suggested. Unless you can see anything that might work out better, I think I'll go with that.

The only question I have about that is what would be the best way to attach it to the wall? I know having some space would help absorb the lower frequencies (right?). How much of a difference would making panel absorbers make as opposed to just putting some hangers up? It's my understanding that the exposed insulation on hangers absorb more high end, which I guess would be bad in my concrete room. Could I compromise and make some hangers with only insulation on the side facing the wall but leave the board exposed on the other side so as not to absorb quite so much high frequencies?

Thanks again for the help, I do appreciate it.

-Cameron
knightfly
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Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

Cool about the "flimsy wall" not being so big, that'll help.

I'm realizing from several different incidences, that I need to post DEFINITE lists of questions, in numbered order, if I need all that information - It's just too easy to focus on only one or two comments when replying; this is something I'm also guilty of, so don't take it as a put-down. I'm merely making an observation "out loud", so I'll remember to change my own tactics...

sooo...

1. I need your actual (studio area) room dimensions, including ceiling height, and whether any dimensions are NOT square -

2. A description of each wall, and the ceiling and floor, as you would see them from inside the room - call the wall that is opposite the doorway North (whether it is or not)

3. I need EXACT dimensions here, to the nearest 1/2" or better if possible -

4. A better explanation of the ceiling - is it wood paneling over 2x10 joists, or just wood joists with the upper floor visible between, or??

Actually, for acoustics the concrete is going to be pretty bright, so you can afford to lose some highs by putting up rigid fiberglas - one way John has done in other studios with great success, is to wrap the fiberglas with thin plastic (like those embossed, 1/2 mil painters drop cloths) and then wrap it with cloth (looks, as well as protection) - with your "open door policy", you could possibly mount 2" rigid fiberglas on sheets of plywood (construction adhesive is good) and then put these up on the side walls on either side of your mix area, angled so they reflect sound to the rear of the room. I'm getting short on time right now, but I can post some basic drawings later on this.

for now, if you could answer all the numbered items we be jammin'... Steve

BTW, I'm about 15 miles east of Albany off I-5 - if you get antsy, we might be able to speed this up on the phone. Don't put your info here though, we can use PM to keep it more private...
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
campersand
Posts: 6
Joined: Tue Sep 30, 2003 3:13 am

Post by campersand »

Okay, here are the measurements:

The ceilings are 7' high and they're made of 1/2' plywood over 2x7 (i know it's weird) joists.

The north wall is all concrete and has a 2' tall, 3' long window 5' from the floor. It also has a weird 3'7" tall metal frame that comes out 2' from the wall and goes for the entire length of the wall, with a piece of 1' particle board secured on the top, like a shelf with storage underneath.

The wall with the entryway is also all concrete and the entryway itself is 5'5" wide and 6'5" tall. This wall and the north wall are each 8'4" wide.

The other two walls are 10'6" wide and both have 1/2" plywood covering the top 2'1" of them.

Those are all the measurements I could think to take. If you need more info, let me know. thanks.

-Cameron
knightfly
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Posts: 6976
Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

The good news: those dimensions, although small, look pretty good on mode spacing (not much coloration of sound due to dimensions) - The bad news - is there any way you can cut the wierd frame/shelf out and get rid of it? It's sitting dead center between floor and ceiling, so it will really screw up the modes. First and third harmonics of room height will be at maximum velocity midway between ceiling and floor, so I would expect that shelf to cause some really wierd artifacts in the room. Also, that's the wall where your speakers should go, so that the open door can absorb a lot of the sound (black hole, sorta)

You haven't said much about sound getting UP into your own unit - not a problem? Big problem? We need to look at ceiling treatment differently depending.

Running behind as usual, I'll check back tomorrow... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
campersand
Posts: 6
Joined: Tue Sep 30, 2003 3:13 am

Post by campersand »

Hey i just wanted to say thanks, I think i've gotten enough info from you to accomplish what I want. sound going upstairs isn't a big deal. the reason it took me so long to reply is that for some reason the site wouldn't let me log in for the last couple days. ? anyway, thanks a lot for all the help. i'm gonna get to work taking out that shelf thingy...

-cameron
knightfly
Senior Member
Posts: 6976
Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

"i'm gonna get to work taking out that shelf thingy..." -

Sic 'em, Git 'em, Bite 'em, KILL... :twisted:

BTW, depending on how "carried away" you want to get, here is a basic plan you can pretty much copy - just pretend your open doorway is a big absorber, and make little ones for the parts of that wall that are still there -
http://www.johnlsayers.com/HR/index1.htm

Be sure and wear eye/ear protection (and gloves) - metal particles (despite the current trend) weren't designed to be embedded in body parts... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
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