About multichannel MIDI devices and Logic Pro for Mac

Multi-timbral MIDI tone devices can simultaneously receive MIDI data on multiple MIDI channels. Each MIDI channel can be assigned a tone or sound, such as piano, strings, bass, and so on.

To take full advantage of the capabilities of such multi-timbral devices, you should use separate MIDI Out ports (from a computer MIDI interface to the MIDI In ports) for each device. For example, use separate MIDI Out ports when you have four MIDI devices that are capable of receiving data on multiple channels and all devices can receive on all 16 MIDI channels.

Logic Pro for Mac is capable of channelizing MIDI data (routing it to MIDI channels 1 to 16) and sending the channelized data to specific MIDI Out ports. When you use a multi-output MIDI interface, MIDI can be separated onto different channels by choosing a MIDI out channel from the MIDI Out Channel pop-up menu in the Track inspector and by specifying the MIDI ports on each device. For example, Logic Pro can assign and send:

• A recording/performance on MIDI channel 1 to port A/module 1

• A separate recording/performance—also on MIDI channel 1—to port B/module 2

• A further recording/performance on MIDI channel 1 to port C/module 3, and so on with subsequent channels and modules

In effect, having a multi-output MIDI interface is something like having more MIDI channels. In this scenario, it would be like having 48 independent MIDI channels, with 16 channels per port (A, B, and C).

Not only does this allow you to play up to 48 different sounds simultaneously through your tone generators, it also provides full MIDI control for each channel of each device. This becomes increasingly important when you are arranging and orchestrating a large number of instrument parts.

If your computer offers several MIDI inputs, you can connect the MIDI outputs of other MIDI expanders and controllers to it.