Here's the theory:

GarageBand draws very heavily on some of the same technology that's used in the pro-level audio products that Apple acquired when they purchased Emagic: the Logic series. One part of this technology is what's called the EXSmkII "Extreme Sampler" in recent versions of Logic, a chunk of software that plays back recordings or "samples" of real instruments (or other sounds). Sampling itself is a really cool technology, and the EXS sampler in Logic has long been regarded as one of the best pro solutions.

Several of the GarageBand "generators" (sound producers) appear to use this same technology, including the drum kits, guitars, basses, piano, strings, horns, and woodwinds. (The synthesizers, organs, electric pianos and Clavinet, on the other hand, look like they use physical modelling technology, but that's another story.) In fact, these generators even use the same file format as the EXS sampler -- if you look in (your hard drive)/Library/Application Support/GarageBand/Instrument Library/Sampler/Sampler Instruments, you'll see a bunch of smallish files, all with a ".exs" extension. These are the instrument definitions; they reference a bunch of AIFF or WAV files located in (your hard drive)/Library/Application Support/GarageBand/Instrument Library/Sampler/Sampler Files.

Since these .exs files appear to be identical to those used by GarageBand's "big brother" Logic, I wanted to see if I could come up with a way to use additional samples. Please note, I think the samples that come with GarageBand are generally pretty good to very good, but I'm always looking to make a cool toy even cooler. After looking around a little, here's what I came up with:

In Practice:

So, let's try one. First job: find an .exs that we can try to add. I did a quick search, and found several here: http://www.ontology.com/exs24/ -- I downloaded the "ontology-upright-bass.exs" zip file. On unstuffing it, you have this:



Now, place the "samples" folder into (your hard drive)/Library/Application Support/GarageBand/Instrument Library/Sampler/Sampler Files. Note: You shouldn't change the name of this folder, or any of the samples inside, as the .exs file will look for the audio files that it wants, here.

Place the "ontology-upright-bass.exs" file into (your hard drive)/Library/Application Support/GarageBand/Instrument Library/Sampler/Sampler Instruments folder. Again, for the purposes of this example, I won't change the name.

Now, to get GarageBand to recognize these files.

Since this is a bass, we'll categorize this sample along with the other Basses, in the "Bass" generator. Open up (your hard drive)/Library/Application Support/GarageBand/Instrument Library/Plug-In Settings, which gives you a list of a bunch of folders within. One of these is called "Bass"; open it up. Inside are a number of ".pst" files (preset files, I assume), which GarageBand's "Bass" generator instrument uses to find the various different samples that it uses -- like this:



Now, make an option-drag copy of any of these presets, and rename it "Ontology Bass.pst" -- make sure that you include the ".pst" suffix, so that GarageBand will know what it is. Now, drag this newly-created file down to TextEdit (or BBEdit, or your own favorite text editor.)

The result will be a bunch of gibberish, looking something like this:



You'll notice that near the beginning, following the "---SAMPSAM1" -- there will be recognizable english -- the name of a sample file, followed by, yep, the .exs suffix. Now, select this sample name and replace it with the name of our new sample file -- ontology-upright-bass.exs

The result will look like this:



Save and close your file -- you'll get a warning that the file is read-only, go ahead and overwrite it. All the mucking with these files is done, now.

Now, open up GarageBand -- note that if it's already open, you'll have to relaunch it for the new samples to be recognized. Double click on a track to get the "Track Info" panel, and make sure that Software Instrument is selected at the top. Now click on "Bass" and select "Upright Jazz Bass", like this (note that you can use any of the existing presets, but this one will give you the right picture to begin with...)



Now, click the Details... triangle, and see what you've got -- right next to Generator: Bass, there's a pop-up menu of presets -- and there's our new generator preset, "Ontology Bass" referencing our new .exs and new samples.




Select "Ontology Bass", adjust your other settings (Compressor, EQ, Reverb...) to taste, and off you go. After you've got it set up the way you want, you can click the "Save Instrument..." button down at the bottom, and make a new Instrument preset that will always call up this sample.

So far, I've had this work with a Largish (150+ Meg) Piano Sample, a 30 Meg Acoustic guitar sample, and this bass sample.

Please let me know if this works for you, or if you run into troubles -- I can be reached at brent (at) fastermac (dot) net.

Going the Other Way (GarageBand to Logic 6)

" From: Jeremy C.
Date: February 22, 2005
To: Brent
Subject: GarageBand to Logic 6
Hi Brent, thank you for your web page titled "Adding Additional Sound Samples to GarageBand". I found it yesterday when I was trying to find a way to use my GarageBand instruments in Logic 6.0. Your page, however, is of course designed for people who are trying to go the other way.
I just completed a utility for doing just that and I would be very happy if you listed it on your page (possibly in the user comments section?).
The URL for it is
http://simon.baymoo.org/universe/tools/garbnd/
Even though I did not use the suggestions on your page, they did encourage me to research the idea of making GarageBand's instruments available to Logic. So I thank you, again.
-Jeremy C. "

(older updates/posts follow from 2004)

(from a reader mail)

" After reading the article on Garageband sound imports I thought I'd let you know something I've found out in Garageband.
I have tried to use a product called Phrazer 2 in the past. It has been the most unstable OSX app I have tried. I was able to simply drag the audio aif files from the finder into a Garageband song with success. Drag and drop Apple.
thanks for the site
Jeff A. "

GarageBand Manual/Tutorials: Apple has posted English and Japanes PDF versions of GarageBand manuals/tutorials ("GarageBand At A Glance" and 3 tutorials) at http://docs.info.apple.com/article.html?artnum=93615.
Apple also has a kbase doc on Maximizing Performance w/GarageBand and Eliminating noise from effects in GarageBand.

46MB of free Loops Collection for GarageBand/SoundTrack (from the Feb. 9th, 2004 news page)

" Access Virus Apple Loops Collection for GarageBand and SoundTrack
Access Music GmbH, the company behind the award winning Virus Synthsizer series, released a free Apple Loops collection for Apple's new GarageBand application. The 46MB archive features punchy arpeggiator patterns, fat filter flows and amazing pad sounds exclusively generated with a Virus C synthesizer. All loops are royalty free and can be used in commercial productions without an additional license.
The Access Virus loop package can be downloaded free of charge from http://www.access-music.de/garageband_freebee/ (requires providing an email address to get the download link)
kind regards/beste gruesse,
Marc Schlaile
Product Director
Access Music Electronics GmbH "