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Last week I was asking how large you should build a sound diffuser. Well here is my video answer and the transcript of the discussion which I hope helps.

Dennis: Alright let’s go back to basics here and remember that a diffuser is an acoustical tool just like a piece of foam, they’re all tools. So what are we trying to achieve with the diffuser? Let’s forget about 4-foot, 6-foot, 8-foot, 10-foot, forget about all that. What are we trying to achieve with the acoustic tool? We know with foam what we’re trying to achieve. We want to control reverberation times and reflections. You hear a big difference in my voice now, versus when I get way back here out of the reflection control of the foam.

So it’s much easier to manage foam or manage reflections when the foam is in the right position for the source and that’s what I’ve said in our last example ‘it depends on your usage how much control that you want’. So forget about dimensions of diffusion.

What do we need to do with the acoustical tool?

Do we want to absorb or do we want to diffuse? Then we select the amount of the absorption or diffusion material that we need to accomplish our objectives. Forget about buying something that has a certain size to it because it’s a good size, that’s not how you should think about room acoustics. You should decide what the issues that need to be managed in your room are and selecting the treatment is not that difficult.

You only have two choices, you can absorb or diffuse. So why would you build a diffuser that’s 8-foot tall? Well you might, in a room that’s 20-foot tall that you want a diffused sound field that’s 8-foot tall. So it all depends on usage. So we make our diffusers 4-feet tall because that’s the highest and best use of materials because in North America the raw lumbers and the materials come in sizes that lend themselves to when you cut a big sheet up to make a diffuser there’s no waste so and that’s standard across the business. But that doesn’t mean that you can’t build larger diffusers, you just have to decide how much surface area you’re trying to cover to achieve what acoustical objective and then the answer could be a diffuser that’s 6-foot tall. It just depends on your usage and what you’re trying to accomplish.

In Summary

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Dennis Foley

I am an acoustic engineer with over 30 years’ experience in the business. My technology has been used in Electric Lady Land Studios, Sony Music of New York, Cello Music and Films founded by Mark Levinson, and Saltmines Studios in Mesa, Arizona, along with hundreds of others.


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