How To Remove Background Noise Using Audacity
Although we recommend that you always record your audio and video files in a quiet location, we know that on occasion, you may find yourself in a situation where you have very little control over the amount of background noise in a sound file. This can produce an audio file that is difficult to hear and even harder to accurately transcribe.
As long as the background noise is not excessive, an audio file can be cleaned up and made to sound a lot clearer than the original. At Transcription City, we use expensive software to clean up your files. However, if you are on a budget and your files are not too bad, you can have a go at cleaning up the background noise yourself using a free software called Audacity.
We have even made a video to show you how!
Step by Step Instructions.
First, Google ‘Audacity’. Go to their website and download the software to your computer, along with ‘LAME’ (which is needed in order to convert your file into MP3 format).
Once the software is installed on your computer, open it up.
To select the audio file that you want to edit, go to ‘File’ and then ‘Open’.
From here, select the audio file that you wish to edit.
Once you have found the sound file that you want to clean up, click on it and wait for it to load in Audacity.
Once it has loaded, you will see the sound profile of your audio file on the screen (it looks a bit like an ECG).
Play the audio and try to locate a section where there is no speech but just background noise. This should look a little bit like a bumpy yet generally flat line on your sound profile.
Once you have found the section that contains the background noise, highlight it and then go to ‘Effect’ (found on the menu bar at the top).
Then from the drop down menu, select ‘Noise removal’. This should prompt a pop up box and from there, select ‘Get noise profile’. Depending on how long your sample of background noise is (the longer the better) you may have to wait a little while for this to load.
Once Audacity has taken the background noise profile, highlight the entire sound file (ctrl a) and then once again, select ‘Effect’ from the top menu. Then select ‘Noise removal’.
This time simply select ‘OK’. This time around you may have to wait quite a few minutes for Audacity to work its magic. Et voila, you have a sound file that is free of background noise!
From there (assuming you have downloaded LAME) go to ‘File’, ‘Export…’ and then save your file in whichever format you would like (we recommend MP3). Then simply fill in the metadata or just select ‘OK’.
So that’s how you clean up background noise with Audacity. We would like to add a note of caution to this: although Audacity can do a very good job of cleaning up your audio files, it is never going to be as clear as recording a good sound file in the first place (see previous posts on how to do this) and you cannot make a bad recording good. However, for minor imperfections in your audio, it’s pretty good and certainly a program we would recommend – especially when you consider that it’s free!
If you would like more information about recording high quality sound files or are interested in using our transcription services for your audio or video files, please feel free to contact us at any time. We are always happy to help.