How to Remove Background Noise In Audacity

If you record podcasts, you probably already know about Audacity. If not, Audacity is one of the most popular open source (and free), cross platform recording tools on the market. Out of the box, Audacity does a great job of recording your audio. However, with a simple trick, you can take your recordings to the next level.

Said trick is removing ambient (background) noise from the recording. Once you start using this trick, you’ll be shocked at how much better your recordings sound.

The first thing is to understand what ambient noise is. Simply put, ambient noise is the constant hum of the world around you. You may not notice it, because you hear it all the time. It’s your AC, your refrigerator, the aquarium in your office, the hum of lights or computer fans. In other words, it’s a steady stream of noise. To get an ideal recording environment, you need to get rid of those sounds. However, you don’t want to have to shut off your AC (in the summer) or your heat (in the winter) to get you recording up to professional levels. And there might be ambient sounds you have no control over (for instance if you’re recording in an office and cannot shut off the lighting or other machines cranking out noise). For those instances, you need to depend on your recording software to remove the noise.

Background noise is not random sounds, like dogs barking, a train, footsteps on the floor above you, a doorbell, or the clicking of keyboard keys. These sounds must be removed manually (and can take significant time to extract).

Now that you understand what background noise is, let’s remove it. I will assume you already have a recording at the ready. You’ll want to do this before you convert the file to .mp3, .wav, or whatever format you require. In other words, this will be an .aup file (which is broken into tracks).

The process for removing background noise goes like this:

At this point, Audacity will remove the noise using to the Noise Profile you created (which was done by clicking Get Noise Profile). That Noise Profile is a sample of ambient noise picked up by your microphone. Depending on how long your recording is, this can take seconds or minutes.

When the process completes, give your recording a listen and you’ll find it sounds exponentially better. With all that background noise removed, your podcast will sound cleaner and much more professional.