Simulating tape loop effects in Garage Band

GB doesn't do either of that, but you don't have to go back to analog - an audio editor like Audacity or SoundStudio will do. With some practice, you can even do it "on the fly", i.e. work on your recordings files while both programs are open.

You could try the free AU Turntablist. That can speed up and slow down audio files nicely. I believe that it has a reverse function as well, but I haven't played with it in a long time.

(page down a bit) http://destroyfx.smartelectronix.com/audiounits.html

Hope that helps.
X

Audacity is freeware, I haven't used it in a while, but it used to be flakey and crash sometimes. I'm very satisfied with SoundStudio, it's shareware with a modest fee and a free trial period. Very easy to use, maybe you just check it out.

The two apps that Christoph recommends are useful.
I've been experimenting with the latest version of Audacity, and so far, it is performing well (I haven't noticed the instability that had been reported in earlier versions).
Sound Studio is also a helpful program.

I downloaded Audacity and messed around with it a little bit. Didn't read the instructions, but it does seem slightly flakey to me too.

What flakiness?

Can you import an .mp3 file into a GarageBand project as a single track within a multi track project?

Yes.

As Windham says, yes, you can use an Mp3, but use the Wav format instead. Why throw out 90% of the musical information before you even begin to work with it.

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As Windham says, yes, you can use an Mp3, but use the Wav format instead. Why throw out 90% of the musical information before you even begin to work with it.

Definitely agree, if that's an option.

I don't give any warranty on this trick, but I used it several times and it worked:

Do your stuff in GB. If you want to manipulate a certain audio region, go to the project folder, look for the recording file, open it in an editor and do your thing even while GB is open. Save it in the audio editor - and voila, GB plays the altered version without a problem. No import/export necessary on the way.

(Caveat: If you change the length of the recording file, GB will almost certainly protest in some way.)

With valuable recordings, you should do a backup before you try this kind of "open surgery" ... 😉

AIFF is a much more widely used format on the Mac (as you guessed, wav is primarily a windows format), so if given the choice I'd suggest AIFF. There is no tradeoff in size or quality, though, they are both lossless ~~Hang

Just so you'll know:
You can import any of the following file formats:
AIFF
WAV (including Sony ACID files)
AAC (except protected AAC files)
Apple Lossless
MP3
Compressed audio files you import into a project remain compressed, saving space and time.
However, there is a definite trade-off: The more compressed an mp3 is, the less of the original info is there for you to work with.
As for WAV vs. AIFF, I haven't noticed a difference in quality between the two, for using in GB.

I haven't checked in awhile, but as I recall in GB 3, imported AAC files remain compressed, other compressed formats are first converted to full sized AIFFs.

Has this changed, Windham? I fear I haven't messed with already compressed files in GB3 B-(>