Using Soundtrack Pro as a Batch Processor

While Soundtrack Pro is only available in the current boxed version of Logic Studio, it is still a useful audio editor to use! David Earl (aka sflogicninja) shows how to use it as a batch processor.  

Soundtrack Pro is one of the most powerful and under-utilized apps in the Logic Studio suite. Many folks who open it up for the first time think that Soundtrack Pro may be redundant, since Logic is going to be the go-to tool for multitrack audio production.

Soundtrack Pro started off as a post-production tool in the film industry. Not only does it have a very capable multitrack audio editing and mixing system, it has a phenomenal 2-track audio editor as well. I liken it to 'photoshop for audio'. It deserves respect!

Today I'd like to show how to use Soundtrack Pro as a batch editor. We are going to open a sound in Soundtrack Pro, apply effects, and create a batch editor using an applescript.

Step 1 - Open an Audio File in Soundtrack Pro

To open an audio file in Soundtrack Pro, simply Control-click on the audio file, and choose 'Open With Soundtrack Pro':

open in STP

You can also open an audio file in Soundtrack Pro directly from a Logic session by using the key command Shift-W.

Once in Soundtrack Pro, we get a classic 2-track audio editor:

2-track audio editor

Step 2 - Adding Effects

To add an effect, use the key command Command-A to select all of the audio file, and go to the 'Process' menu. We're going to choose 'Reverse':

Reverse the file

Now the entire audio file is reversed. Let's now go to Process > Effects > Reverb > PlatinumVerb:

Adding Reverb

Now we see the reverb plugin. To apply the reverb, choose 'Apply' in the lower right hand side of the plugin window.

Next, let's reverse the audio again! Press the spacebar to hear the new reverse-reverb effect.

On the left-hand side we are shown a list of the processes we are applying. Feel free to re-order the list of processes. It will re-process the file and you can hear reverb before reverse, after reverse, or un-check the box, and we get no reverb at all. This is the magic of Soundtrack: we are given several layers to the sound.

Applescript for reversing reverb

Step 3 - Create An AppleScript

Now that we have a nice little process for quickly making a reverse reverb, let's add this process to our AppleScript library so that we can simply select the preset process, rather than set it up every time from scratch.

Go to File > Save as AppleScript...

Name this AppleScript 'Reversed Reverb'. Note that the AppleScript is automatically going into a folder dedicated to Soundtrack Pro Applescripts.

Save as Applescript

Now you can access this Applescript from your AppleScript Menu in Soundtrack Pro:

Applescript menu in STP

Now let's batch convert an entire folder of audio quickly and easily.

Step 4 - Batch Converting a Folder Using AppleScript

Now save another AppleScript to your desktop, instead of the folder Soundtrack Pro has made for you already. You'll see this icon on your desktop now:

Applescript icon ready to use

If you grab an entire folder of audio files over this icon, all of the audio in the folder will automatically have the settings applied that we created before. No need to open up Soundtrack Pro. Simply drag the folder of audio files onto the applescript icon, and watch it go! (Or go make yourself a drink)

The only caveat is that you need to use PCM audio files. Not OGG, MP3, or any other compressed format. Soundtrack may not recognize them.

Have fun!

David writes music for all media including advertising, branding, movies, television, and games. He works for such clients as Sega, LucasArts, Microsoft Game Studios, Landor and Associates, Beyond Pix, Rich Pageant, and Nextel. He also teaches at an Apple Certified training facility in San Francisco called Pyramind and has long bee... Read More


David Thx,

but another thoughts.

Hi Miloslav

Yes, perhaps we could've mentioned that STP will process audio files in this way in a destructive manner (i.e. altering the original file) and therefore, of course, it is always important to make a copy of the audio file if you wish to keep the original intact.

However, the article in your link is describing the process of applying noise reduction which assumes you'll be tempted to work on the original file. Indeed, in that situation, you really should be making backups of your audio file first or exporting to a new file from within STP.

You could actually build in a number of automator actions/scripts to duplicate the original file first before one of the copies gets processed in STP.

Hey there!

With hard drive space being less expensive as the years roll by, I highly recommend that all audio to be batch processed should be copied to a new folder before processing.

As for the linked article, I understand Larry's concerns regarding the source audio being effected without chance of undo, but copying the folder is pretty quick and painless for even the largest audio project.

For noise reduction, I would create separate folders for different recording environments. These environments would have their own individual noise prints, given that the location audio includes room tone. This means separate scripts for different environments. I need to do a bit of research to see if noise prints are included in scripts. You cannot use the same noise print on very environment.

Each folder would be batched individually. Noise reduction can be tricky, due to potential volume fluctuations that may increase artifacts in the noise reduction. This is why having copies of the files is important.

I think Larry is right in saying that the best result would be to process individual files. I also know production schedules, and sometimes speed trumps quality depending on the project.

Also, all projects should be backed up either by using Time Machine or a program like Chronosync. This way if you have screwed up the original audio, it can be replaced with an original very easily.


Hallo David,
Hallo Rounik,

Thanks for reading and solution.


Gary Hiebner
Excellent tutorial. Soundtrack has some amazing effects and processors which I wish Logic will incorporate. Hopefully in Logic X?

I think you may be on to something. :-)

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