wrapping my head around isolation.

blue642 · Post by **blue642** » Tue Jul 11, 2006 2:34 am

Ok, so me and a friend/coworker have been tossing around the idea of building a rehearsal studio.

I have been reading the forums here for a couple of weeks now and doing a lot of reading/researching during lunch breaks (almost daily) and at home during the nights.

one thing I can't wrap my head around is true isolation and ratings of soundproofing.

I have read here that STC ratings mean pretty much nothing in studio isolation.

here's the thing, we plan on building some rehearsal rooms and want to design it so that even though some rooms will be next to each other, it's pretty much totally isolated and sounproof from noise travelling between the rooms or out into a hallway.

I found this reference http://www.saecollege.de/reference_mate ... 0Chart.htm

and was planning on building walls similar to the 6th one down, 3 layers of 5/8" gypsum on 2x4 frames filled with fiber insulation and about a 5 inch gap between the frames. ( a total 12" gap between leaves) but how do I know this will be enough to withhold a typical rock band?

That site says that it would be roughly 61 db STC ( I'm unsure what gap size they used, and it's staggered frame) but I have seen charts where 60db is rated as normal conversation levels.

also does anyone have a reference of what db range a typical rock band praticing in a room might be?

any help is much appreciated.

knightfly · Post by **knightfly** » Wed Jul 12, 2006 4:55 am

Typically 100-115 dBA; to isolate, you need to understand separate TL (Transmission Loss) at each frequency range - extreme low end (around 50 hZ) takes about 50-55 dB before the threshold of human hearing is reached, so if you can accomplish 50 dB of TL at that frequency (not an easy task) then the rest of your isolation should pretty much take care of itself.

That's because the higher the frequency, the easier it is to block - that's why I recommend building for LF TL. Once that's covered, you're more or less home free.

Here's a basic sketch I did for a Spanish member;

http://www.johnlsayers.com/phpBB2/download.php?id=4141

he substituted locally available products without asking me (or having time to wait for an answer) so there are marginal things about that particular implementation, but this WILL work if built as shown... Steve

z60611 · Post by **z60611** » Wed Jul 12, 2006 5:26 am

typical rock band

http://www.bobgolds.com/WallCharts/Quad ... eafSTC.htm
http://irc.nrc-cnrc.gc.ca/pubs/fulltext/ir761/ir761.pdf

knightfly · Post by **knightfly** » Wed Jul 12, 2006 5:37 am

And "Database Bob" strikes again; thanks Bob - ever the gentleman, ALWAYS the useful sources... Steve

blue642 · Post by **blue642** » Wed Jul 12, 2006 12:57 pm

Thanks for the replies guys, great resource material!

Steve- if we built with all brick/block would we expeience a harshness of higher frequencies being reflected (somewhat typical in concrete buildings)

Also, We wanted to implement the front/entrance wall to have dual sliding glass doors which would be our weak point. Is it much much harder trying to keep sound in, when using lighter weight glass doors? (lighter than solid steel)

agaiun thanks for the tips.