How to Convert Stereo to Mono in Audacity

What are Stereo and Mono?

Whenever you are editing your audio files on any digital audio workstation you will notice either one or two audio waves.

stereo mono audacity differences

These are some of my recent projects. A is Audacity which has a mono audio file, B is Adobe premiere with stereo audio, and lastly, C and D are Adobe Audition with Mono and stereo audio recording respectively.

For Audacity, this setting is not only available during editing, but you can set either of these preferences before you start your recording.

The difference between mono and stereo sounds is that mono signals are recorded and played back using a single audio channel and stereo sounds are recorded and played back using two channels. So basically mono means one, and stereo means two. Before you do start your recording you will be prompted on any recording software that you are using to either save the file as mono or stereo.

Quick tip to follow this, you have your home studio set up in place and you want to record a quick solo podcast episode. The recording should be set as mono as you only have one audio source that is you. The next day a friend hops in as a guest then you will have to set the recording as stereo. Now let us look at a case where you already have a file, it is in stereo and you want to convert it to mono.

Converting Stereo To Mono in Audacity

Audacity allows for both mono and stereo recording and editing.

audacity side by side comparison of mono and stereo audio files

First, let us look at converting audio that was recorded in stereo to mono.

Launch audacity then import the audio file using Ctrl + Shift + I keyboard shortcut or click File then import and then click on Audio.

importing audio in audacity

Your opened file should have two channels just like this.

two channels audio in audacity

From the options on the menu bar click on tracks. Under the drop-down, there is the mix option. If you hover your mouse on that option an additional drop-down option appears. Under this click on Mix stereo down to mono.

mix stereo down to mono audacity

Once you click on ‘mix stereo down to mono’ your file will be converted into a mono file.

mono file conversion audacity

After this play your audio to make sure everything sounds okay. Check for issues like your audio level.

Another Method of Converting Stereo To Mono in Audacity

Alternatively, you can use this procedure. Once you have imported your audio file you will notice a panel on the left side of your screen. It is highlighted in the image below.

left panel audacity

Next to the file name, there is an arrow pointing down. Click on that to open a drop-down menu. Once the menu is open scroll down to the ‘split stereo to mono’ option.

split stereo to mono audacity

Once you click on the split stereo to Mono option your audio file will be split into two mono files. How do you know this? In the above image, there is a yellow line with black borders around your audio file. With the command that you have just done, you will be able to toggle between the two files and select them separately by clicking either of them. On the image on the left, the upper audio is selected and on the image, on the right, the lower one is the one selected.

two mono files in audacity

Once you have established that your stereo track has been split into two mono tracks as explained above, you will then proceed to delete one.

Go back to the panel on the left side of your screen. There you will notice an X icon next to the name of the file. Click on the X to remove the one that you settled on for deletion.

deleting one mono file

 Once you click on the X the bottom one is removed.

bottom mono file removed in audacity

Note: Do not select the one being deleted and remove it using the backspace and delete buttons. If you do this essentially you are like muting one and not entirely removing it.

Here is a quick confirmation to look at and confirm whether your audio is mono or stereo. Check the panel on the left. There we have details of the file that you are editing. In the image below the audio is mono, the frequency is 44100Hz and 32-bit float is what you gauge your headroom in this audio file.

mute solo left panel audacity

After this, you can choose to save the project or if you are completely done with the editing at this point you can export the audio file.

To export go to File under the Menu Tab options. Scroll down to the Export option. Hover your mouse over this option for another dropdown option to appear. Under this click on export as Mp3 or Wav depending on what format you prefer your audio to end up as.

export to mp3 audacity

Input the desired file name as well as in what folder you are saving it. Lastly, click Save.

saving file audacity

Why Would You Convert Stereo to Mono?

About 2 years back a client sent me a recording. Here is the file in Audacity.

why convert stereo to mono in audacity

Looking at the highlighted areas comparing the red against their respective counterparts you will realize that the left channel is different from the right one. In this case, I had to convert this file to a mono file. If only some edits were done and the conversion was not done the audio would have an imbalance where when someone listens to it at about minute thirty their right side on their speaker or headphones would have no audio playing back.

Note that neither of the channels should be louder than the other. You can countercheck all the images with stereo files in this article to confirm this.

Recording in Mono

Now since I have addressed an already edited audio file it is only fair that I take you through the process of recording. You have your equipment set up and everything is plugged in correctly, launch Audacity.

Click on edit under the menu tab option and then click on preferences. Alternatively, you can just press Ctrl + P.

recording in mono

This dialogue box will pop up.

choosing devices for recording in audacity

 Under the recording option, there are two drop-down list options, device, and channels. Click on channels. You will now have two options to choose from.

choosing mono option when recording

Press OK to apply these changes. Once you click on the record button you will either have a mono track or stereo depending on the channel option that you did pick.

Remember one source like a vocalist or if you are recording a single podcaster then record in mono. If there are multiple voices do record in stereo.

In Conclusion

You know have the know-how of converting an audio file from stereo to mono.

Stereo sounds compared to mono tracks are better as they have this realistic edge, a wider element, and the listener feels immersed.