Do you have a recording needing Audacity noise reduction?
Are there unwanted noise in your Audacity recordings? The hum of the freezer, random sounds from outside the window? If so, good news, Audacity can remove these background noises for you, here’s how…
You should probably make sure you read how to record crystal clear audio in Audacity to get the best recording quality before even hitting record. Long story short, record in a quiet room, watch out for the computer’s fans and also don’t stay too close to the microphone. But you have what you have, and if there are unwated background noise, here’s how to remove them.
Open Audacity and your file
The first step is to open Audacity and click file>Open and open your recording, you should see your timeline like this:
Tell Audacity what noise is
What’s next is to tell Audacity what “noise” is. You will need to select a small part of the track and tell Audacity that this part is noise, to remove it. How to do this?
First select a small part of your recording where the noise is. You might need to zoom in the track to select the part of the recording that contains noise. Click on it and select the recording, like this:
While this part is selected, go in effects>noise removal. You will get a dialog box, click on “Get noise profile”
What this does is tell Audacity what to remove in the whole recording. Once that is done, you will return to the normal timeline. It might seem like nothing happened, but Audacity has the noise profile loaded in the background. Now it’s time to tell Audacity what part of the recording to apply the noise reduction to. In most cases, you want the whole recording, if that is so, select the whole recording (Ctrl+A or Select>All). The part where the noise reduction will be applied will be highlighted like so:
All you need to do is to go to Effects > Noise reduction (yes, AGAIN) and this time click “OK”. For long recordings this might take a while, but once you are done, Audacity will have cleaned the background noise with noise reduction.
Advanced Audacity noise reduction
In case your recording has multiple background noises, say there is a “hum” and a “click” in the background, first select the part where the hum is, get noise profile and then apply it. Then go the the “click” part and do the same.
In conclusion, noise reduction is very useful, but it’s not magic. The best thing you can do is to simply have the best recording from the get-go and then apply noise reduction.