How to Convert a Mono Audio File to a Stereo File

By Erick Kristian

Converting a mono audio file to a stereo file is a relatively simple process using standard audio editing programs like Adobe Audition, Sony Soundforge or Cubase or Cool Edit Pro, each of which can be purchased for a few hundred dollars. Of course the final product will not be true stereo as the recording was mono, what will happen is that the mono track will be placed in both the left and right channel simulating true stereo sounds. Fortunately, it is nearly impossible to tell that the audio was not originally recorded in stereo.

Things You'll Need

  • Audio editing program

Step 1

Download and open and audio editing program. Cool Edit Pro and Adobe Audition follow very similar steps to complete this task. Cool Edit Pro was acquired by Adobe and is now rebranded as Audition. Import the mono audio track by clicking "File" and then, "Open."

Step 2

Click the "Effects" tab, then click "Amplitude" and "Channel Mixer." Under the preset menu select "Both = Left" or "Both = Right," depending on the channel in which the mono track was recorded. If the audio track takes up the top half of the screen then it only has the left channel. If the audio track only has the right channel then the bottom of the screen will contain the audio track. For example, if the audio track is on the top of the screen, that means the original audio recording was mono left, which means the right channel needs to be filled to make it stereo. So the user would select "Both = Left" then click "OK."

Step 3

Wait while the program renders the new audio track. If everything was done correctly the opposite side of the screen (top or bottom) should be filled with a new audio track. The audio track is now in stereo.

Step 4

Save the file. Click "File," "Save As." Use the Windows Explorer window and navigate to a directory where the new file will be saved. Under "File Name" enter the name of the new stereo audio file. Under "Save as Type," select the file format to save the file, such as MP3 or WAV. It is a wise idea to save the new file in the original file's format. For example if the original file was a WAV, then save the file as a WAV. Click "Save" to save the file. Exit your application. Navigate to the directory where the new file was saved, double-click it to play and ensure the file is now in stereo.