Sound Treatment for 5,400 sq ft sound stage

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janesrichard
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Location: Oklahoma City, Oklahoma, USA
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Sound Treatment for 5,400 sq ft sound stage

Post by janesrichard »

Hi there,

First thank you so much for hosting this forum John, it's been a real eye opener reading through the posts.

We are in the process of converting an old school in Oklahoma City, Oklahoma, USA, to a non profit film academy. The main gymnasium is a 5,400 sq ft FIMA rated tornado shelter. This means all the walls and the ceiling are 1 ft solid concrete and this is what we want to use as our film sound stage. Our location is in the middle of the countryside with no trains, planes, or heavy traffic so once you are inside the gym you can't hear anything outside, it is fantastic. The size is 92' long x 59' wide x 27' high.

However, as you can imagine, it has terrible acoustics. Our goal is to place a treatment on the walls and ceiling to absorb all the sound in the gym resulting in clean audio to be recorded (mostly speaking/acting, no music).

I initially looked at covering everything with insul-quilts as that tends to be industry standard for new studios. But that would come in at around $100,000, which we just can't afford.

I was lucky enough to visit the old MGM studios in Hollywood last year and managed to look at their treatment which in some cases hadn't been updated since the 40's and had big holes in the walls so I could take a look in the wall. It seems like they used some kind of fiber glass, covered it with material and then put a wire mesh over it so that it wouldn't get damaged.

If that worked in the 40's (and they still use those stages) I am hoping we can do something similar.

My thinking is:

Line the walls and ceiling with 2' x 4' RockWool SAFE'n'SOUND.
Place a black material over the Rockwool to stop any fibers and keep it somewhat tidy.
Place 2 inch wire mesh over the lower 10 ft of the walls.

A few questions:

Does RockWool make the most sense in this situation?

To attach the RockWool to the wall, my thinking is to build 2x4 wooden batons horizontally along the wall spacing them out every 6 ft. Then attach the rockwool to the wall with green glue. Does that make sense? If yes, should the wooden batons be attached to the wall with green glue or do we drill those into the concrete? I certainly don't want it all falling down :-)

What would be the most cost effective material we could use to cover the RockWool? I read somewhere someone say use simple garden membrane but that is not fire resistant and it looks to me that that might reflect sound.

We might be crazy but we'd love to keep the material costs between $15,000 - $20,000.

Thank you for any suggestions you might have. Plan attached.
OFTA-Main-Stage.jpg
DanDan
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Re: Sound Treatment for 5,400 sq ft sound stage

Post by DanDan »

Suspended Ceilings are very good bang per buck. Readily available materials and skills. Great acoustic performance. Be careful to use fully absorbent tiles, not the 'Office' type which have a reflective back with a CAC specification. Maybe the 2'x4' one McDonalds use, or faced 705 ones......
I would include a layer of light cheap insulation above the tiles.
Just musing...... 1"x8" beams at regular intervals. Install fibre in every second one. On the opposite wall fill the alternating ones, checkerboard style.
You could use wooden laths to contain and protect the bottom part.
sandledfoot
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Joined: Wed Sep 13, 2006 2:40 am
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Re: Sound Treatment for 5,400 sq ft sound stage

Post by sandledfoot »

I treated a gym with Tectum... it was for plays/speech presentations, etc... but it worked fairly well. It was durable, could be painted and damped the sound.

I can't remember exactly the price, but It was well shy of 100k, but i'm certain was over 25k.

http://www.johnlsayers.com/phpBB2/viewt ... f=1&t=9366
studio construxcion.... it hurts my brain.
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