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Old 9th August 2019
Lives for gear

This is one of the reasons why acousticians try not to use the word "soundproofing": because it confuses people into thinking it is something that it isn't!

What you are trying to do is usually called "isolation". Meaning that you want to "isolate" the inside of your room form the outside world. "Isolation" is not a material: it is a process. There is NOTHING you can hang on your wall to isolate the room... because isolating the room means that you have to isolate the ROOM: All of it. Not just part of one wall, or a corner. The entire room needs to be isolated, in the same way that you need to put glass on all sides of a fish tank, if you want to keep the water inside. If you only put glass on one side, or two sides, then the water will still gush out all over. Likewise, if you only isolate one wall of your studio, or two walls, sound will simply gush out through the other walls, and the ceiling, and the floor, and the windows, and the door, and the HVAC system, and the electrical system.... Isolation is the process of preventing sound from getting out through ALL of those parts of the room.

So that's the basic concept: it's "all or nothing". If you don't do all of it, then you might as well just do nothing at all, because your results would be pretty much the same.

Contrary to popular believe, you can't isolate a wall (or a room) by putting up panels of insulation, or bass traps, or diffusers, or things like that. Those are acoustic treatment, for the interior of the room, to make it sound good, but they do a sum total of zero for stopping sound from getting in or out. Treatment is usually done mostly with soft, fluffy, light-weight, flexible, low density materials. Isolation always involves hard, rigid, solid, massive, heavy, high density materials. The exact opposite. Isolation and treatment are two totally different aspects of acoustics, with very little relationship be between them.

OK, the basic process for isolating your room goes like this: Get a sound level meter to measure how loud you are inside the room when you are playing, and also how loud that is outside your room, at the location where your complaining neighbor is. Get a copy of your local municipal noise regulations to find out how quite your sound are legally required to be, by the time it gets to your neighbor. Do the math, and you will come up with a number that tells you how much isolation you need, in decibels. With that number in mind, look at the various documents, reports, graphs, tables, etc. on the forum to find out what type of construction you will need to have for your room, in order to get that level of isolation. There will probably be a few options that you can choose from: Quote the price of those building materials and the labor needed to do the work, and chose the option that is least expensive. One good document here is IR-761, from the Canadian National Research Council. I shows hundreds of different ways you can build your walls, with the isolation you will get from each of those. They have similar publications for floors, and you can extrapolate the same information when designing your doors and windows.

So that's the basic procedure.

- Stuart -