Batch Concatenate MP3s (stripping long pauses)

Every day I have a new folder of MP3 files that I need to concatenate and strip long pauses from. My needs are quick/dirty, so I’d rather not get into waveforms. Can anyone offer guidance re: scripting this? Unfortunately, I’m not able to use anything deeper than applescript/automator.

If it can’t be scripted, is there an optimal workflow that will make this as efficient as possible?

I’m on a Mac (but felt the query belonged here rather than on the MacOS board)

How long are the supplied pauses and how long do they need to be?

Are the supplied pauses “clean?” Do they drop to absolutely no sound, or do they have hummy, buzzy, shuffling, background sound, Room Tone in the pauses?

One of the problems with automating a “Dirty” (noisy) track, is you have to play the whole thing anyway to make sure it worked right.


Drag’n’drop the entire contents of the folder into Audacity, then use “align tracks end to end”.

Truncate silence can do that, (you determine what constitutes silence).

Audcaity has its own batch-processing thing called Macros.

Thanks much. While I’m here, there are some copy problems on the “Truncate Silence” manual page (

In the “Examples” section, the word “Level” is used, when the in-app word is “Threshold”.

Is there a place I can go to propose this correction or make it myself? Or is it sufficient that I’ve reported it here?

The “Truncate Silence” effect has had a minor update. In the old version, the first control was called “Level”. In the new version the first control is called “Threshold”. There’s no difference in what they do.

The manual has now been updated, but the update will not appear until the next release.
If you would like to proof-read the new version, it’s here:

The new manual page you linked me to continues to use the term “level” in the examples rather than “threshold”.

Oops, sorry, wrong link.
I’ve now corrected the link to:

Looks very good. I particularly like how you refer to “threshold level” earlier on, repeatedly. That will help bridge the change of terms.