September 17, 2016

How to Use the 'Boost and Sweep' Method to Get Rid of Problems in Your Audio

Here's a way to make problematic audio sound a whole lot better.

If you head into post and notice that some of your audio has some unwanted noise—maybe you've got some low humming or something going on in the background—then it might help to do an EQ sweep. In this tutorial, editor Dan Bernard shows you how to EQ using an additive EQ technique, or the "boost and sweep" technique, in order to locate and repair problem frequencies.

The method Bernard uses is called the "boost and sweep" technique—you boost a frequency to find problem areas in a frequency band, and once you do, you (hopefully) fix them by pulling that frequency down. This might work in many cases, but there are other methods for EQing your audio. In fact, some sound editors say that the "boost and sweep" method might lead you down a lengthy rabbit hole, because finding bad frequencies is fairly easy if you're looking for them by boosting frequencies.

You can try the "subtractive EQ" technique, which is basically the exact opposite of the "boost and sweep"—you simply cut frequencies instead of boost them to find problem areas.

How do you EQ your audio? Let us know in the comments below.     

Your Comment

7 Comments

Very cool! Can this be done in FCPX?

September 17, 2016 at 9:42PM, Edited September 17, 9:42PM

0
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Richard Krall
richardkrall.com
1487

Yes, under the effects browser go to the audio section. Add the effect "Channel EQ". Then go the audio tab, in the inspector, and under the effects panel you'll see Channel EQ. On the right of the channel eq title is a square button that looks like an audio board. Click that button and you'll see fcpx version of what Dan's is messing with.

September 17, 2016 at 11:35PM

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Thank you!

September 18, 2016 at 2:16AM

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I thought this would be standard. I started doing it out of thin air. The subtractive method might be best, because it likely will be in more than one frequency range. By subtracting you van pick out the spread and balance out creatively what you want to keep and where you want to.keep it, because invariably it will overlap with wanted niose and even the actors. So tradeoffs are in order, unless you have software that van restore missing frequency in acturs voices and other desired sounds, while isolating out the noise in those bands that is not the actor. Sounds like a new product. Simply, you hear actors in other scenes, and if you change their voices too much, it sticks out.

Wayne.

September 18, 2016 at 4:19PM

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Wayne M
Director of a Life
375

How - do you do it ? As little as possible.

September 23, 2016 at 10:10AM

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This seems like a good idea.

Using noise reduction like in Audition can work to some extent. I've also thought that using a gate would be a good idea but haven't had enough luck with that yet to really advocate it.

Unfortunately, I've found that sometimes it's better just to leave the noise in there because sometimes the sound treatment winds up being more noticeable.

September 26, 2016 at 12:40PM, Edited September 26, 12:41PM

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Dan Q.
168

This sounds a bit tedious. Most audio editors should have a noise-reduction feature that can automatically detect and remove the offensive frequencies from your audio clip.

At least in Audacity (which is a free audio editor), you just have to select a few seconds of background noise and it will remove that noise from the whole clip.

September 28, 2016 at 1:26AM, Edited September 28, 1:26AM

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