The MIDI function in GarageBand allows you to use "virtual instruments" to create melody lines, bass lines and percussion. Virtual instruments are digital synthesizers contained within the program that you can control with a MIDI keyboard or computer keyboard. In addition to recording music using thousands of customizable synthetic sounds, you can perfect your MIDI recordings by quantizing them. Quantizing simply refers to fixing the timing, so that each note falls exactly in time with the beat.
Instructions
1. Select your MIDI track (or one of your MIDI tracks) with your mouse. Your tracks are the long, spanning bars appearing across your project window. To highlight a track, just click the track title in the left column.
2. Click the region that you want to quantize. Your regions are the individual recordings that appear on the tracks (shaded green), which may span 4, 8 or 16 (or sometimes more) beats.
3. Open the GarageBand track editor. Along the bottom of your screen, you will find a picture of a pair of scissors. If you click it once, it will turn blue and expand, displaying a horizontal grid with all of your MIDI notes laid out.
4. Click the "Grid" button in the upper right corner of your track editor, and select a number from the list. If you have numerous notes on each beat, and you want to ensure precise timing, you might use the "1/8" or "1/16" sensitivity. For slower songs, with only one or two notes per beat, you can use the "1/4" sensitivity.
5. Click the "Fix Timing" button in the lower left corner of your editor window. Your notes will then adjust according to your specifications, leaving you with a more polished sound.
6. Select additional tracks and regions to quantize additional synth lines and recordings. Some regions may require very precise timing specifications (like 1/16 or even 1/32) while others require only simple adjustments (like 1/4 or 1/8).
