If you haven’t already tried listening to an entire song in GarageBand, try it now. You can click Play at any time without wreaking havoc on your carefully created tracks. The music stops soon because your loops are only so long. Most are five seconds in length, and others are even shorter. To keep the groove going, you have to do one of three things:
Resize the loop. Hover your cursor over either the left or right edge of most loops, and an interesting thing happens: Your cursor changes to a vertical line with an arrow pointing away from the loop.
That’s your cue to click and drag — and as you drag, most loops expand to fill the space you’re making, repeating the beats in perfect time. By resizing a loop, you can literally drag the loop’s edge as long as you like.
Repeat the loop. Depending on the loop that you chose, you might find that resizing it doesn’t repeat the measure. Instead, the new part of the loop is simply dead air. In fact, the length of many loops is limited to anywhere from one to five seconds.
However, if you move your cursor over the side of a loop that you want to extend, it turns into a circular arrow, which tells you that you can click and repeat the loop. GarageBand actually adds multiple copies of the same loop automatically, for as far as you drag the loop.
Add a new loop. You can switch to a different loop to change the flow of the music. Naturally, the instrument stays the same, but there’s no reason you can’t use a horn-riff loop in your violin track (as long as it sounds good played by a violin)!
To GarageBand, a software instrument track is compatible with any software instrument loop that you add from the Loop Browser as long as that loop is marked with our old friend the green musical note.
You can also use the familiar cut (Command+X), copy (Command+C), and paste (Command+V) editing keys to cut, copy, and paste loops from place to place — both on the Timeline and from track to track. And you can click a loop and drag it anywhere. After all, you're working under Mac OS X.
Each track can be adjusted so that you can listen to the interplay between two or more tracks or hear how your song sounds without a specific track:
Click the tiny speaker button under the track name in the list, and the button turns blue to indicate that the track is muted. To turn off the mute, click the speaker icon again.
You can change the volume or balance of each individual track by using the mixer that appears next to the track name. This comes in handy if you want an instrument to sound louder or confine that instrument to the left or right speaker.
A track doesn’t have to be filled for every second with one loop or another. Most songs have a number of repeating loops with empty space between them as different instruments perform solo.