Concatenating Lots of Small MP3 Files

For audiobooks, I prefer AudioBook Builder, which takes a bunch of mp3 files and merges them into the audiobook format instead. Advantages of this format is chaptering and the ability to remember where you left off listening.


You can actually use the unix command line utility 'cat' to do this. Open terminal.app (in your /Applications/Utilities folder). You then need to get to the directory these files are in, so if in ~/sys.stderr/book, then cd ~/sys.stderr/book/)

Then you can run

cat *.mp3 > audiobook.mp3

Assuming these are all in the right order name wise, they will be added.

Some tips would be to:

  • backup the original files
  • make sure they are all the same bit rate
  • strip any current ID3 tags out of the original files
  • rename them in the order you need (file1.mp3, file2.mp3, etc)
  • do the ID3 tagging after you are done through iTunes or another tool.

There's more information in this Mac OS Hints post as well.

If you don't want to use cat, you could also open up GarageBand, make a new file, and then open all the current mp3's and join them together. Then export that new large file as an MP3 of the audiobook (sorry, not on my Mac right now, so don't have screenshots).