Posted by Mark on June 26, 2002 at 18:28:43:
In Reply to: Re: Re: Re: The perfect practice room posted by Rick Denney on June 26, 2002 at 15:18:53:
The rug trick is fine, especially with the air gap as you installed it. I did the same thing to fix an echo in my dad's living room. Even Egg-crates and all that stuff is fine, as long as the user knows what it can and can't do. One can do wonders with cardboard cartons, fiberglass insulation, carpet over a calculated air-gap, or all kinds of common, cheap things if done in a calculated fashion.
You'll not see these things in recording studios or auditoriums because they are (pick one): ugly, hard to clean, flammable, not trendy, not UL approved or whatever.
Disclaimer here: In a different context than discussed above, Rugs & carpets could make a bad room worse. The reason why the rug warmed-up Rick's former practice room is beacause rugs/carpets absorb mid & high frequencies almost exclusively. I'm sure Rick knows this. I mention it because many folks don't. Also, the carpet itself makes a difference. Many churches and schools have made the mistake of gluing industrial grade carpet or fabric to the lower walls of gymnasiums, only to find almost zero change in acoustics. Tight weave, short pile, hard-wearing synthetic carpets glued to hard surfaces still reflect most sound.
I've seen on this BBS, in the past, folks advocating carpeting the walls of a room as acoustic treatment. This will probably make the room dead & echo-free sure enough, but will leave frequencies below about 250 Hz (approx, fundamental of middle C) untouched. Compound this effect with likely low-frequency modes, and you have a room that would only be good for a piccolo player that you don't want to hear. If the room was "muddy" or boomy sounding before the carpet, It will be even more so after.
Ooops. To answer Patrick's original question: For my dollar, No. There is no cheap way to actually soundproof a room. Interior acoustics, maybe Yes. The room in question would have to have NO residential-grade windows or doors, and would need to have walls that are: (1) airtight, including window and door perimeters; (2)Either much more massive than typical (3) or more rigid than normal, like portland cement over cinderblock.
My Office/practice room/music room has 5/8" plaster over 1" cement board on rough-cut 2x4's (a 1950 construction, before drywall. Much heavier than double drywall) on both sides, and fully gasketed solid particleboard-core door. My wife is happy, but about 45 decibels of a 95 decibel honk still get through. I could do better, but it's not worth the cost right now. It is reasonably quiet but not truly "soundproof".
Staggered studs done right would work pretty well, If you're building from scratch, but still will let some sound thru if you're playing Tuba. Low frequencies are just hard to stop.
Mark "I never took physics in high school cause I was scared of math" Mazak