Though none of the software instruments that come with Apple’s Logic DAW/sequencer support multitimbral operation, the program does support multitimbral operation with Audio Units synths and samplers. There are two ways get make this work:
1. Each Audio Instrument track in Logic can contain MIDI information on multiple channels. Just instantiate your instrument as usual, then record or create MIDI data in its track on whatever channels you want to use. Be sure to set the MIDI channel in the track parameter box to “All.”
2. A second option is to create multiple separate Instrument tracks and assign them to the same Audio Instrument. Then record separate MIDI channel information into each track. For each Audio Instrument Track you create that’s addressing the same Instrument, set the MIDI channel to “All.”