February 5, 2018

How to Eliminate Echoes When Recording Sound in a Big Empty Room

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If you're recording audio in a reverberant room, echoes are going to become a huge problem. Here's how to get rid of them.

So, you're planning to shoot some scenes that take place in a bathroom, warehouse, or some other type of reverberant space? Well, that's pretty awesome, but wait until you realize that you'll have to eventually record sound in a room full of echoes, which is especially challenging when dialogue is involved.

While ADR and post-production software can help avoid or (kind of) fix this issue, you might want to know a few tips on how to eliminate echoes so you can record sound on set without them bouncing all over the place and ruining your recording. In this video, Michael Lohrum of DIYCameraGuy explains how to "treat" reverberant rooms so you can do just that.

Every surface will reflect sound waves to some degree, but those that are hard and smooth, like a tile floor or bare walls, do it best. This is why it's important to put up obstacles that absorb sound waves and cut down on echoing. In the same way that every surface reflects sound waves, they also absorb them, but it's your job to figure out which ones will absorb them enough to eliminate echoes.

Of course, sound blankets were made for these types of situations, but if you don't have any on-hand, Lohrun suggests finding materials that are heavy enough to absorb sound waves and porous enough that sound waves can pass through it, bounce off of other surfaces, and pass through again. This means clothes, normal, everyday blankets, towels—really anything of that nature.

Then, when it comes time to record audio, just throw the material on the reverberant surfaces, like wood/tile/etc. floors, walls, bathtubs. You can even throw a blanket on a boom and hang it close to your subject to try and cut down on any reverb.

What are some other clever ways to soundproof an echoey room? Let us know down in the comments.      

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7 Comments

Are there any other ways?

February 6, 2018 at 11:02AM, Edited February 6, 11:02AM

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Terry Smith
Marketing Manager
22

Cheap synthetic duvets, works a treat.

February 6, 2018 at 2:00PM

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February 7, 2018 at 12:07AM

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Then, when it comes time to record audio, just throw the material on the reverberant surfaces, like wood/tile/etc. floors, walls, bathtubs. best slimming belt You can even throw a blanket on a boom and hang it close to your subject to try and cut down on any reverb.

February 7, 2018 at 1:47AM

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wasi
1

His CRAPPIE boom pole idea is brilliant and all I use when I'm doing sound for anyone. Nice one.

February 7, 2018 at 10:48AM, Edited February 7, 10:48AM

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What about a directional mic in podcasting?

February 8, 2018 at 5:12PM

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Wayne M
Director of a Life
335

I liked the way that super-reverberant room sounded. I say if you're stuck with something like that, make it part of the emotional and creative arc of your film. Use it for the scene where the couple is fighting and they are saying the same thing but not listening to each other, or an actor doing one of those voice of God monologues, or a character alone with her thoughts and you hear her breathing. Or watch the Harbor Freight ads and buy a bunch of their moving blankets when they're on sale.

February 9, 2018 at 2:29PM

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Richard Swearinger
Freelancer
105