Film-Tech Forum ARCHIVE: DIY sound absorption panels

This is topic DIY sound absorption panels in forum Ground Level at Film-Tech Forum ARCHIVE.

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Posted by Dan Chilton (Member # 2288) on 03-03-2008, 04:34 PM:

Has anyone had experience building their own sound panels to cut the echo in an all concrete screening room? What type of material will deliver the best results for the least amount of money? I've heard good defenses for covered rockwool insulation slabs, as well as canvas covered MDF board. Any other suggestions?

Posted by Tim Reed (Member # 137) on 03-03-2008, 04:48 PM:

The canvas covering or burlap works well. So does short pile carpeting glued to the wall about half way up. Then trim with scattered canvas panels. Leave some exposed concrete wall sections on the sides, of course, as you don't want it totally dead.

Posted by Cameron Glendinning (Member # 3516) on 03-03-2008, 04:59 PM:

Well the first question is are the speakers installed properly? The Horn loaded design of the typical cinema speaker if installed and angled properly, can in many situations, stop the refections off the walls before they even start.

Personally I have used black tissue faced fiberglass duct liner aprox 3.2 kilos per square metre, hung a few inches off the wall. (ie air gap behind is good). As most cinemas have the most audio reflection problems backstage, I tend to put the fiberglass there, not in the auditorium.

To break up sound and early reflections all that is needed is random 3d patterns and angles. Speakers aimed at flat surfaces tend to cause the bounce problems.

Posted by Louis Bornwasser (Member # 3063) on 03-03-2008, 06:18 PM:

Made out own covering in London, Ky using "duct liner" (see above) 100% coverage above 40". Louis

Posted by Blake Zaugg (Member # 1455) on 04-04-2008, 12:14 AM:

We did this at a theatre I was at previously.

The frame was 2x4's and then just regular insulation inside, covered with fabric.

Was surprising the difference it made.

Fabric had to be special non-flamable type.