Split Stereo To Amplify One Channel

Windows 10, version 3.5.1

In the past I would occasionally split the stereo tracks in order to apply slight amplification to one channel in order to balance the sound levels. I then put the tracks back together and moved on.

After I updated to the latest version I’ll perform this function but when I tic the “Make Stereo” box it takes about 8-9 minutes to to recombine a 2 hour track and it says something about remixing it. It takes about 4 minutes to recombine a 4 minute passage. I’m just checking to see if this is normal.

It is “normal” for recent versions of Audacity.

Older versions could split and join channels without re-rendering the channels. This was recently changed, which I think was to work around problems handling tracks with real-time stretch, so that joining mono tracks renders the tracks to create a new stereo track, rather than just sticking the mono tracks together. Rendering tracks is comparatively slow because it processes the audio data sample by sample.

If you mean that both of the mono tracks are around 4 minutes, and the resulting stereo track is about 4 minutes duration, then that seems excessive. I would expect it to take about half a second.

Is this issue repeatable in new projects? If so, please provide step by step instructions for how to reproduce the issue.

My friend has a 3 hour show and I catch the internet stream. Stereo of course. Occasionally one channel is slightly lower than the other. At the left side I click the down arrow and choose “Split Stereo Track”. I’ll highlight an area between labels on one track only, could be 4 minutes long, apply the amplification I need and then click “Make Stereo Track”. The progress box appears and it says “Mixing And Rendering Tracks”. I just tried it with a program I recorded using version 3.5.1 and a four minute section, one channel amplified, took 5-6 minutes to occur. A past version of Audacity was nearly instantaneous in combing the tracks back to stereo.

Thanks for all you folks do.

When the mono tracks are joined to make a stereo track, then entire track is rendered, not just the part that you modified.

There’s a quicker way to make both channels have the same peak amplitude.

  1. Select the region to process
  2. Open the Normalize effect
  3. Set the required peak level, and enable the “Normalize stereo channels independently”.
  4. Apply

A more flexible way is to use the Channel Mixer plug-in. This plug-in allows you to amplify the channels independently.

1 Like