John Sayers' Recording Studio Design Forum Archive

Just use 12mm plaster sheet javier - that will work.

John is it called Homosote or Homasote? The link you posted earlier to www.pinnacleboard.com lists it as 440 Homasote. Does this look like the right product? http://www.homasote.com/products/440-Soundbarrier.aspx

leif - it sounds like by the description - it says it's made from cellulose fiber which is what the product I use is made from.

Watching some builds over gearslutz forum, Ive seen a couple of studios making hangers out of 1/2" plywood (M Wagner Studio)

one of the amazing factors of Tom Hidley's hangers, and mine, is that you can move one, and the others follow. You can cause a wave of energy to flow down the chain of hangers by affecting one of them, they are light.

definitely not heavy 1/2" plywood.

but each to their own.

Lowes has a product that looks like Homasote. http://www.gp.com/BUILD/product.aspx?pid=6055 John does this look like it would work?

doesn't look like it Lief.

this is what the stuff I use looks like
It's also called tack board or pin board and is used as a backing for notice boards..

Me again

John, I have some 6mm OSB leftovers that I could use for the rec room hangers. Will them work like the 12mm plaster you mentioned or should I go for plaster

yes - you could use that Javier.

Hi friends

After thinking a long time, i decided to give the hangers a shot, and build some hangers of leftover 12mm osb in the upeer controlroom corners.

After installing them on one side and at the front celling i think i understand how the work.

when i touch one of them, the next starts to swing , but in a different phase. so the air between the hangers gets compressed and then decompressed, which is not more or less than a spring. I think not the size of the hangers is the main faktor for the frequency range they work in, it`s the distance between each hanger what gives the resoantfreqency . For shure a hanger must be big enough to be present for a soundwave, but thats another storry.
As i understand it, the insulation is used for 3 things:
1. dampening the spring effect
2. dampening the pannel resonance(vibration) itself
3. work as a normal porous absorber for high and mid freguencys.


I just treated a third of the basstraparea with hangers until know, and did a soundtest yesterday night.

It works realy great. The room sounds even in the bassrange, just with athird of the hangers inside (only the small ones) , without backwalltreatment, and so on.

My ear just realized a small dip at around 50 hz when i played a sweep, but for that amount of treatment it`s a very good result.
I think the finished room will sound great an even.

here is a pic of the hangers in place:






cheers
Mika

Great to see you went with hanger. Too bad the picture's not showing them right

in france it's called "isorel mou"

hope this help

best

Philip Newell writes in the appendix (page 664) of his "recording studio design" book about hangers.
To sum it up, more research has to be done, but they don't work on the resonant absorber principles that many believe that they do. Instead they work by changing the acoustic impedance. This is similar to wedges in an anechoic chamber, or layers of soft absorbers on the inner layers then harder and harder materials as you approach the outer layers of a room. They could work a bit like an inverted horn, where velocity is converted to pressure. In my opinion they might be related to an acoustical lens (the fins that can be seen covering the tweeters on some speakers). They present an different impedance to the sound wave, then the surrounding air.

Construction on my studio is coming along but has been slow. was just bumming around the forum looking for ideas when i came by this thread. It looked interesting so i did some quick research for options tht might be available in India and i think this is practically the same thing (almost), better also maybe because it looks like a well finished material. Its water resistant and manufactured from cane fibre.

http://www.jollyboard.com/bitumen.html

and a question i had was are these (bass hangers) a viable option for smaller rooms. 13x7x7.5 approx. If yes where would be the best place to position them. Or is it better to have cornerfilled bass traps in such rooms.

I had a thought about the presentation of acoustic hangers.

Does anyone see a problem with just wrapping the hangers in fabric instead of building a cloth-covered frame to encase them?

Thanks,
Seamus

EDIT:
Sorry.
Already was answered here:
http://johnlsayers.com/phpBB2/viewtopic ... 24&start=0