Often, when you’ve recorded something that’s out of tune, you’ve just got to record it again. But before you do, try fixing it in GarageBand ’09, which comes with a few tools for tweaking pitch. Here, I’ll walk you through the process of using these tools.
1. Double-click on the region you want to work with. This will select the region as well as open up the Track Editor. (If the Track Editor was already open, this will hide it; if that’s the case, double-click it again.)
2. To the left of the region, you’ll see three sliders: Pitch, Enhance Tuning, and Enhance Timing.
Enhance Tuning is a very powerful control when used in moderation, say, with values of less than 10. It’s great for evening out the performance of amateur singers, who (if they’re like me) often have trouble holding long notes in one place. Try increasing the amount (moving the slider to the right) gradually until you begin to hear artifacts–strange crackly sounds–and then dial it back down until the artifacts disappear.
I recommend not checking the Limit to Key box; in my experience, it mangles the original. But by all means try it, and see how it works on your music.
3. But what if you wanted to take a whole region and bring it up or down a bit in pitch? This is where the Pitch slider comes in (before trying this, bring the Enhance Tuning slider back to zero). However, be warned: On a range of voices and guitars, I’ve found that it creates highly garbled, artifact-ridden output. It might work better with instruments that have distinct, uniform pitches, such as pianos or harpsichords. By all means experiment, and see if does the trick for you.
If it doesn’t, the next step is AUPitch. But before we go there, zero out the Pitch parameter in the Track Editor, and close the Track Editor.
4. AUPitch is Apple’s own Audio Unit (AU) plug-in for handling pitch. Select the track you want to work with, and click the View Track Info button at the lower right to show the Track Info window (if it’s not open already). Click on the Edit tab, then click on the first available empty gray Effects slot to call up a menu of available effects. Scroll down to the Audio Unit Effects section, and select AUPitch. Click on the AUPitch icon (it’s a generic Audio Unit “sun” icon) to open AUPitch for editing.
5. Like the Track Editor’s Pitch slider, AUPitch lets you raise the overall pitch of a track up or down. But unlike Pitch, AUPitch has a few different parameters to help reduce artifacts and produce natural sounding tone. Your success using any of these controls will depend on your source material, but here are a few guidelines:
Maximum Render Quality is not necessarily best. In some cases I’ve had best results with Medium.
100 Cents is a half step, and 1200 Cents is one octave.
Effects Blend, if not at 100, will mix the original sound with the pitch-shifted sound.
Turn Smoothness up to remove certain kinds of artifacts.
Turn Tightness down to remove other kinds of artifacts, but at the expense of losing some depth; if it sounds too “thin,” bring it back up.
So before you bring that oboe player back to re-record an out-of-tune part, try tweaking it with a few of the tools that are right there in GarageBand ’09.
[David Weiss is a San Francisco Bay Area based freelance writer.]