Logic Pro X Stereo to Two Mono


What would be the fastest way to split/convert a few hundred stereo tracks to mono. I can route them through busses and auxes to new tracks and record them but that gets a bit tedious with hundreds of tracks.
I suppose I could export as non interleaved and then do a batch filename change,but is there a more efficient means within logic?
There are many options and it depends on your setup and your needs which one you use:

Here are four places where you can switch to Mono:

Make it Mono
the first step is to merge the 2-channel stereo signal into a mono signal

1 - Input Format
When you have stereo Audio Regions on a Track, you can set the Input Format (the circle buttons) on the Input Button to Mono. That merges the signal to mono. Using the File➤Export➤Region to Audio File will create a mono file.

2 - Audio FX Plugin (Mono) on Channel Strip
If option 1) is not possible because you have stereo Plugins on that Channel Strip that you want to keep, then you can add the Audio FX Plugin "Gain" at the last slot of the Channel Strip and set it to Mono. Now the Channel Strip has a two channel mono signal at its output. If you need that Gain Plugin on multiple Channel Strips, then keep in mind that you can with select all the Channel Strips and load a Plugin on Channel Strip and it will be loaded on all selected Channel Strips (Ad-hoc Group functionality). Or, you can load it on one Channel Strip, make the setting (switch to mono) and then option drag that Plgin to other Channel Strips.

3 - Audio FX Plugin (Mono) on Output Channel Strip
If you don't want to create individual Plugins on all the Channel Strips, You can also add the Gain Plugin on the Output Channel Strips and set ti to mono.

Once your signal is merged to mono, you have different options to export/bounce it to mono files.

A - Export Region
You can use the File➤Export➤Region to Audio File command on individual Audio Region when you use option 1 and 2

B - Bounce Stereo Output Channel Strip
Use the "Split" option in the Bounce window and it will create two separate mono files for the left and right output channel, which are indentical at that point. Just use one of the files and toss the other redundant one.

C - Bounce Mono Output Channel Strip
With this procedure, you click on the Input Button of the Output Channel Strip. It toggles it between stereo (two circles) and one (one circle). Now you have two separate Output Channel Strips (one for the left output channel and one for the right output channel). the cool thing is that both Channel Strips have their own "Bounce" Button, when you use that button, you create a single one-channel audio file for the signal routed through that Output Channel Strip. I demonstrate that functionality in my new book "Logic Pro X - Tips, Tricks, Secrets #1".

Here is a screenshot from that section


Thanks Edgar, but I don't want to merge the two channels to a mono file. The two channels are different unrelated tracks but were delivered to me as stereo files. Basically I have 224 mono tracks from a tracked album delivered as 112 stereo tracks. I can split them one ata a time but hoped there would be a fast way to do it.
I see. The only way I can think of is use the "File ➤ Export ➤ All Tracks as Audio File" command

  • Create two Audio Channel Strips
  • Set the Input Format of the First Audio Channel Strip to "Left" (Control+click on the button and select it from the popup menu) and set the second Audio Channel Strip to "Right"
  • Now select both Tracks and option+drag them down, which creates 2 new Tracks with duplicate Settings
  • You have to do that 111 times to create the 224 Tracks. You can use a trick and select-copy bigger chunks of Tracks the more you created (drag 4, drag 16, drag 32, etc)
  • Now import your 112 Audio File, where you put every Audio File on two adjacent Tracks (one set to Left and one set to Right)
  • If now all the Audio Region start at bar 1 and there is only one Region on each Track, you can use the All Tracks as Audio Files command, and Logic creates this 224 split mono files.
If you spend some time in the Finder, properly naming the Audio File before importing them, then Logic will place them correctly on the Tracks and you can use the Export command and you are done in on step. What I mean is, duplicate all the 112 files in the Finder and add an a letter or two to the file names ( you can batch rename that in the Finder, ctr+click on the selected files and choose "Rename", or you can use the Automator app for more detailed operations). This way the Audio files and their duplicates are listed sequentially when you sort them and are placed correctly when importing them into Logic. Does that make sense ?

Here is a slightly different procedures for Logic.
  • Import the 224 audio files and let Logic create the 224 new Audio Tracks.
  • Now use the "Ad-hoc Groups" feature. That means, you select Channel Strip 1 and every other Chanel Strip in the Mixer. Changing the Input Format on one Channel Strip to "Left" will change all those selected Channel Strips to that format
  • Now do the same thing for the even Channel Strips. Select Channel Strip 2 and then every other Channel Strip. Select Input Format "Right"
  • Use the Export command and you are done.


That's close to what I did to split the first track. It worked. But I think I'll see if I can come up with an approach that does need to be repeated dozens of times


You don't have an old running copy of Logic 9 do you? If so, try unchecking "Universal Track Mode" in the Audio Preferences and importing your files. It should split them all on import, then you can copy them into your Logic X project.


I don't have 9 installed any more. Looks like de-interleaving and detect silence is a pretty simple way to go.


I get a stereo file after doing this (gain plugin with mono on after stereo plugins).
This is a 5yr old thread... so I'm guessing the original poster has long-since gotten this figured out (or maybe they're still tediously bouncing each of the hundreds of tracks )... but to the recent poster's follow-up... the best way I can think of to do this in a big batch is in the Project Audio Window (key-command "F").

Presuming you've imported all of the stereo files into a session that has no other regions in the audio file list...
  1. Simply select all (or a bunch of) stereo files
    Screen Shot 2020-07-30 at 8.26.32 AM.png
  2. Open the "audio-file" menu (from THAT Project Audio view)
  3. Select "Save Region(s) As..."
    Screen Shot 2020-07-30 at 8.26.40 AM.png
  4. Ensure you've chosen "Interleaved to Split" in the 'Stereo Conversion' options on the "save as" dialog
  5. If you don't want your newly-split .L / .R files to be zapped back into this session, un-check the box at the bottom for "Add resulting files to Project Audio"
  6. Save
    Screen Shot 2020-07-30 at 8.27.23 AM.png


Alex, thanks for the diligence. I can only just remember why I was doing this now. I think I did a batch change in DSP-Quattro, but will make a note of your post in case someone sends me another load of files like this.


That’s cool! I loved DSP-Quattro until the most recent version. I’m not a huge fan of the V5 UI.

anyway... glad you solved your need, but I thought it was worth posting for any future users who have similar questions


A lot of people didn't like the V5 changes at first, but there were a few quick updates to get around the more difficult parts of the new interface, like have to open a project to open an audio file. It takes a bit of exploration. After using it for a little while, I could see now why he made these changes, and I'm pretty happy with it.


Yeah — no knocks against Stefano and his app. It's great, and he's wonderful... I just had a very specific workflow, for which V4 and earlier versions were perfect. But I am such a heavy keyboard-shortcut user, and the way the new menus are designed, they're not configurable from the Apple Keyboard Shortcut Prefs... so it really slows me down.

Thankfully, the newer versions of iZotope RX (which was always a second part to that workflow) have even better workflows for region marking & exporting... so I actually do all my "simple file slicing and clean up" directly/fully in iZotope RX 7 before brining the exported files into Logic for assembly & mastering.


Yes, that's not great if you depend on shortcuts. Would have been good if he had put shortcuts in the preferences at the same time as the rearrangement of the menus. As it is you'd need a third party keyboard macro editor to deal with it.