sound proofing

Probably not the right forum but would appreciate any advice on how to sound proof a room. I don't record. Just want to be able to mix and listen through speakers instead of earphones without upsetting the wife and also cut down on the TV/radio/chatting coming from the rest of the house. The room has a half open wall right now facing the house so I can insulate that with anything.

thanks

John

Dave's suggestion is a good one, but I'm going to suggest some research before you spend the money and time required to build a reasonably soundproof room. It will pay off in the long run.

Briefly -

Two things are required to prevent sound from crossing a boundary
- mass - or isolation - so that the boundary does not move, and
- no path for air to travel across the boundary (not really practical if you plan to be in the space, but it is a requirement!)

Mass is easy, sand filled block is massive, as is loaded vinyl, and certain loaded sheet rock like products. But they are all expensive, and they are all expensive to install. And if that is not expensive enough for you there are specialty products on the market that claim to provide better than sheet-rock isolation...

Air tight is neither easy nor practical, so you'll need to settle for the fewest possible paths!

The first step is to determine just how much transmission loss or isolation you really need at each boundary.

As an example:

my back basement has two block walls covered with dirt on two sides, a block wall facing a yard where the
closest neighbor is still several hundred feet away, and the last wall separates the studio space from a play room.

So I don't really plan to do anything at all about the first two walls, and I won't need a lot on the third. The fourth wall (and the ceiling, more on that shortly) is my problem, and that's where I'll spend the money.

I need better than 55 dB of isolation to keep sound in, and while I'd like more, I can live with that for keeping sound out. I normally monitor at around 85 dB-spl, 55 dB of transmission loss will reduce what does get out to around 30 dB-spl, which is below the actual ambient noise level in the adjacent space.

A wall capable of 55 dB loss is easy to build, so I'm going to design for 65 dB - but that's another issue<G>!

For the three block walls I'll stud out a new wall six inches (maybe a tad less) from the block and apply overlapping layers of dissimilar sheetrock. I'll use metal studs to eliminate the need for fancy fasteners, but wood construction works too, you just need to use the "Z" clips sold by most acoustical product suppliers.

The last wall will be a double wall constructed of two isolated stud walls, the inside wall will be metal studs, the outer wall will be wood. Same two overlapping layers of dissimilar sheetrock on the outsides. No clips on the wood studs as I want to avoid the too-many-springs problem.

I will put insulation in the spaces between walls, but I'm not sure what kind or how much.

That's the 5 cent version anyway... hope you can get something useful out of it!

The ceiling, which separates the studio from the family room, is my real weak spot. I will end up hanging a fairly massive ceiling on the new walls to isolate it from the rest of the structure. On paper it ought to work... in practice, well, I don't know. I've built similar structures in the past, but never for quite as demanding a client!

The HVAC system is a potential source of problems, but I'm lucky, AC part is in the garage, and it will be relatively inexpensive to run new, isolated ducts. I'll use my computers, old tape decks, and amplifiers to heat the space, an when that isn't enough I'll use electric baseboard.

All doors and windows will be doubled - these are generally the weakest part of any sound proofing project, but the cost to overcome that weakness is huge, so I'll use solid cores, and lots of weatherstripping!

krizrox

Mod Bod


A double wall with two sheets of gypsum board (5/8-3/4" thick) on both sides.  Fill the wall with 3" thick mineral wools and put a prehung exterior door in it leading into the rest of the house.

Hopefully there is ventilation to this section of the house? Airtight rooms with no ventilation get really hot really quick.

This is true and exactly the reason I budgeted for a separate A/C system for my project studio.  I figure that his room already has duct work and if he just wants enough sound proofing to allow him to work then a good solid wall and door is the first step. 
 
If he tells me that he has $14 - 20 Gs to build out a space then we'll really start talking. 

Thanks... and to everyone. Right now there is a "no wall" on one side, typical wall on two sides, and the other side is to outside with a window. Outside noise is nil. The side with no wall is the one that accesses the most noise (both ways) so I can fool around with building that... needs a door too. There is ventilation in the room.

Strangely, the room will also double as a guest room with a murphy bed which I assume will also deaden noise so I'll put that against the wall to the room where my wife hangs out doing needlepoint etc. while listening to TV.

Contractor, who knows nothing about sound proofing, coming over tomorrow and will show him all your ideas and see what he says. Will let you know what evolves.

John

 

jackn2mpu


For one of the best online freebies on acoustics, go to the Auralex site and download the Acoustics 101 pdf - a ton of good info there. Here's a link so you can either download the pdf or go to a subsite that has the pdf contents online:
http://www.auralexelite.com/resource_center/acoustics101.asp

Just remember that soundproofing and acoustics isn't necessarily the same thing although if you do one, you will always have to include the other as a result.

That report from Auralex is great, I learned alot from it.  I built a room inside a room (Inside my garage actually)  about 5 yrs ago & It would not have come out as well without that document & without auralex products.  I built 2x4 walls 16" on center with 2-3 braces bettween each stud, I stood the fram walls on a 2 layer strip of sheetblock, then applied 1 layer 5/8ths drywall to the outside, 2 layers (staggered seems) inside with sheetblock in bettween.  On the ceiling because I could not install drywall above my new room (only about 6" off existing ceiling)  I installed 2 layers of MDF with sheetblock in bettween to the inside of the ceiling.  When I got done my metal Exterior grade door was the week point for sound,  So with the door closed I traced out the jam on the door, & then cut & screwed a layer of MDF to the inside of the door to increase the doors mass & weight.  It worked well.  I then added Auralex studio foam & bass traps to help interior acoustics.  I can have the band playing at full tilt, Live drums (with an animal playing them), full stacks, & pa....  my wife can sleep or watch tv with no problems & not a single neighbor complaint in 5+ yrs.

If you have any questions I'd be happy to help!  I am new to sonar, but soundproofing I am pretty good at!
 
EDITED: Typo