Back dead wall

How to use REW, What is a Bass Trap, a diffuser, the speed of sound, etc.

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moby
Posts: 122
Joined: Wed Feb 23, 2005 7:40 am
Location: Belgrade

Back dead wall

Post by moby »

I started few days ago with building my studio and used all John's layout suggestion
http://johnlsayers.com/phpBB2/viewtopic ... c&start=15
So, it's time to decide about inside acoustics :roll:
I finally find a source for material close to oc703 and oc705, and i was thinking about mix of them on the rear wall of c. room.
Something like this....
What you think about :?:
knightfly
Senior Member
Posts: 6976
Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

The higher density absorbents tend to have better absorption at STRAIGHT incidence (sounds entering at perpendicular, or 90 degrees) but usually ALSO tend to have more sound grazing off at OTHER angles, due to higher density/less open weave; and since very little of sound in a small room is as simple as a 90 degree angle, I tend to stay with lighter weight absorbents such as 703, Roxul AFB's, all around 40-48 kG/m^3.

For your back wall, if you can stand the loss of floor space for smoother sound, I would build a STRAIGHT frame across between the two outer points, use hangers where there's room (per John's suggestion on your design thread), put your703 between the studs and cover with cloth.

That will give you deeper bass absorption due to the extra air gap behind the insulation batts - it will probably ALSO reduce some "focusing" of sound back to the mix position due to the partly parabolic shape of a slightly convex rear wall. If you had the room, you could even bring the CENTER of this "absorber wall" forward so it's convex when viewed from the mix position; this for even deeper bass absorption.

Another alternative would be to slant that rear wall into the room at its top, making more volume of space for bass hangers/trapping, but without a serious decrease of usable floor space... Steve
moby
Posts: 122
Joined: Wed Feb 23, 2005 7:40 am
Location: Belgrade

Post by moby »

Cool, it's clear :D I'm just not clear about hangers dimension. Can somebody point me to the topics with that info?
Thanks, Sergio
knightfly
Senior Member
Posts: 6976
Joined: Sun Mar 16, 2003 11:11 am
Location: West Coast, USA

Post by knightfly »

moby
Posts: 122
Joined: Wed Feb 23, 2005 7:40 am
Location: Belgrade

Post by moby »

Thanks, thats's great info :!: :wink:
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