Recording a MIDI Bass line OK, as the next step, let’s add a 4 bar MIDI bass line over top of the drum loop and high hat tracks: Within the Transport window, click and drag the MIDI Thru Channel popup to set it to channel 1. Click the Play button in the Transport window or press the spacebar to start playback. As the sequence plays, select a bass sound on your General MIDI sound module and work out a 4 bar bass line to go along with the drums. Click the Stop button in the Transport or press the spacebar once you’re figured out your part. From within the Tracks window, click the R column to record enable track 4 for recording. Click and drag the Output popup on track 4 to assign it to Channel 1 of your General MIDI sound module. Click the Record button in the Transport or press Option-R to begin recording your MIDI bass line to track 4. (Remember, the count off is set to 1 bar.) Click the Stop button in the Transport or press the spacebar after you’ve played in at least 4 bars worth of material. Within the Tracks window, click the Loop button to loop the bass track and specify 4 bars for the track duration. Choose Save from the File menu. This saves the contents of the active session to the current Metro file. The next step in your first session is Recording Another Track.