How to remove background noise in Audacity for cleaner podcasts

Woman with headphones on working on laptop.

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Podcasts are everywhere. No matter the subject, you'll find a podcast. 

But not all podcasts are created equal. 

You might have the perfect idea for a podcast that will blow people's minds, but if you cannot produce quality-sounding episodes, you'll lose listeners. 

From my perspective, within the realm of podcasts, there's nothing more off-putting than poor audio.

Also: The best podcast app doesn't come from Apple or Google

What is background noise?

The first thing we need to talk about is just what is background noise. Think of this as your AC or heat running. It's the constant hum you might find that seems to be a natural part of the room in which you record. For example, in my studio, I have a very large aquarium with two massive lights that require fans to keep cool. My CAD E100S mic picks that up every time. Because of that, I have to remove that background noise.

What doesn't count as background noise is unpredictable interruptions like random dogs barking or cars driving by. However, even those sounds can be removed in this same fashion, so long as you can locate them in the timeline.

Enough of the blathering. Let's get to the action. Ready?

How to remove background noise in Audacity for cleaner podcasts

So, how do you remove background noise from your podcast files before they are submitted? If you're using Audacity, that task is much easier than you might think. Let me show you.

Requirements

The only thing you'll need for this is Audacity installed on Linux, MacOS, or Windows. The operating system doesn't matter, as the process is the same. You'll also need a recorded file to work with, but I would suggest you not test this process on a production file just yet. Make sure to use a test file first. Either that or make a copy of your production file, and try it out on that. Truth be told, this is such a simple process that you most likely wouldn't harm your audio recording. However, as with everything, it's better to be safe than sorry.

Thus, without further ado…

The first thing you'll do is either open or create a test file in Audacity. 

If your situation is like mine, you've got background noise running throughout the entire file. If that's the case, highlight any portion of the timeline that doesn't contain voices (or other important sounds).

The Audacity timeline editor.

Selecting a portion of a track to use as a Noise Profile.

Image: Jack Wallen

Click Effect and then Noise Reduction, which will open a pop-up.

With the noisy section selected and the Noise Reduction popup open, click Get Noise Profile, and then click OK.

The Audacity Noise Reduction pop-up

Applying your noise profile in Audacity.

Image: Jack Wallen

You now need to select the entire track that needs noise removed. You can do this by either clicking CTRL-A on your keyboard (if all tracks need to have the same noise profile removed) or using your cursor to select the track that needs noise removed.

Go back to Effect > Noise Reduction. When the pop-up appears this time, simply click OK and Audacity will remove all noise associated with the noise profile you selected. When it finishes, you should hear a much cleaner track than what you had previously.

And that's all there is to removing background noise from your podcasts with Audacity. It's a bit of a cumbersome process but it works like a charm. If you want your podcasts to sound as professional as possible, consider this a must-do for every file.

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