Since GarageBand 1.1, the program has had the little-known capability of using SoundFonts as a sound source (using the DLSMusicDevice AudioUnit). It’s not perfect, but it does work for simple 1-instrument SoundFonts (as well as the first voice of more complicated ones). Also, the excellent (and free) Crystal AudioUnit can use SoundFonts as an oscillator source. However, both applications want you to keep your SoundFonts in a separate directory. We can fix this with a Stupid Unix Trick(tm).
Crystal wants its SoundFonts in ~/Library/Preferences/CrystalSoundFonts/. GarageBand (and the DLS AU) want them in /Library/Audio/Sounds/Banks/. Since this is more of an OS-central location, we’re going to use that as our SoundFont repository.
Step 0: be sure to close any AU Hosts you’re currently running (GarageBand, Logic, Rax, etc.) It probably won’t make a big difference, but hey, a little caution never hurts.
Step 1: Move the contents of your CrystalSoundFonts folder into /Library/Audio/Sounds/Banks/. (you can do this with the Finder or Terminal. Your preference). Delete the (now empty) CrystalSoundFonts folder.
Step 2: (I find this to be easier in Terminal, so open it. It’s in /Applications/Utilities/)
Enter the following in your Terminal window:
cd ~/Library/Preferences
ln -s /Library/Audio/Sounds/Banks/ CrystalSoundFonts
Step 3: There is no Step 3, unless you count closing Terminal and firing up GarageBand again!
What we did here was make what’s called a “symbolic link”, or symlink pointing the CrystalSoundFonts directory to /Library/Audio/Sounds/Banks. Now when Crystal looks for SoundFonts, it will find them in /Library/Audio/Sounds/Banks.
I’ll probably have some more SoundFont-related material in the future, as I’m trying to build Swami on OS X (and currently failing miserably). Anybody have a nice all-in-one build (a la Gimp.app)?