Often times it's better to use a ClickTrack instead of the built in metronome. The advantage of a ClickTrack in Apple's GarageBand is really two fold. First, since the ClickTrack has its own fader, you can change its volume without affecting the rest of your project, often times allowing you to hear the beat more easily. The second reason is feel. Since you can create any type of drum beat for your ClickTrack, you can craft one that better fits the feel of your music, which can help you record your other tracks more accurately.
To get you started I've created 7 loops, in a .zip file below, which you can drop into your own projects while recording, feel free to use them as you wish.
The 7 ClickTrack loops are freeware, for you to use and enjoy as you wish.
Download HT's 7 ClickTrack Loops (v1.0.0)
GarageBand from Appl Computer uses audio loops and MIDI loops in Apple Loops format. It can work with Audio Units plug-ins. Apple Macintosh Compatible FireWire and USB interfaces can be used to connect Audio and MIDI instruments to your Mac, and be recorded into GarageBand.
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