Reading Marty's "Birth of a shop, the final trimester" someone mentioned using insulation to sound proof the walls of his shop to his office. I thought I'd make a illustration or a model of how we made sound proof walls in the apartment complexes I used to build as a younger fella, we never used insulation to do this...just the stagger stud method.
I thought with everyone building shops or are going to build... this thread might come in useful.
Between every dwelling we would frame a common wall and stagger the studs to allow a cavity for the noise to deaden and keep the next dwelling from hearing what the neighbors were doing in their apartment.
These weren't used in motels as I'm sure many can attest to the noise doesn't stay within the walls of the other guests in a motel. The apartments we built were 24 unit dwellings...24 families per complex, so I'm pretty certain these walls did what they were intended to do.
I made a model showing the procedure we used...
*Note, this may not be scale but does illustrate the framing procedure.*
Starting out with a set of 2x6's for top and bottom plates, you next do a layout of 12" centers with every other 2x4 stud on one edge of the plate, the studs in between are still on layout but on the opposite edge of the plates. Frame the entire wall this way with the end studs being 2x6 to keep the noise within the walls.
I tried to illustrate drywall being used on one side to show the cavity with the opposing stud to deaden the noise. Drywall was used on both sides in the apartments of course but leaving one side off gives a view of my intent.
If you are using a 2x4 wall you could do the same thing only turn all studs one quarter turn. If you have the room to frame two walls side by side and a few inches apart you can accomplish the same effect with 2x4's instead of 2x6's. What you are doing is creating a dead space for the noise to diminish.