Fastest way to separate channels for large number of files?

Hello all,

I am trying to find the best possible way to achieve the following:

  • split track into left and right channel
  • delete left channel
    (- ideally: remove excessive silences in track)
  • save track

This is all well and good except I have to do it on approximately 25,000 individual tracks.

Can someone recommend the best way of achieving this that doesn’t involve manually repeating the steps above 25,000 times?


It would be possible to process up to about 1000 files as a batch provided that all of the files are in the same folder.
Audacity has a batch processing feature called “Chains”, but it can only work with files that are in one folder.

See here about Chains:

You will also need to install “Channel Mixer” which you can download from the Audacity wiki:
Installations instructions for this plug-in:

You will then need to create a “Chain” that uses the Channel Mixer plug-in to copy the right channel into the left channel, then apply the “Stereo Track to Mono” effect, and finally export in the required format.

You may be able to do that by adding “Truncate Silence” to the Chain.
I’d recommend that you try out Truncate Silence and test it thoroughly with a selection of files before you try adding it to the chain.

Hi Steve, thanks so much for the quick response. Do I still need the Channel Mixer if I want to discard the right channel? I’m only interested in the left channel in the output.

You wrote in your first post that you wanted to delete left channel.

There is no command available for chains to discard one channel. So what you need to do is to copy the channel that you want to keep, to the channel that you want to remove (both channels now have the audio that you want to keep). Then you can convert the stereo track to mono (which will give you the average of both channels, but as they are now identical you will get the equivalent of the one channel that you want to keep.

Apologies, my mix up. Will try your suggestions and report back. Many thanks!

This worked a treat, thank you so much for your help.