Here's how to set up an External Instrument track for your MIDI device:
1. Click New Tracks to create a new track in the Arrange window.
2. Click Software Instrument in the New Tracks window then click Create.
3. In the channel strip to the left, click the input insert (the field directly below "I/O") and choose External Instrument > Stereo (for stereo) or External Instrument > Mono (for mono) from the menu.
4. The External Instrument window opens.
Note: If it doesn't open, double-click the plug-in. You can control whether plug-in GUIs open on insertion in the preferences. Choose Logic Pro (or Logic Express) > Preferences > Audio... and click the General pane. Select the checkbox for "Open plug-in window on insertion."
5. Click MIDI Destination to display a menu that lists the MIDI devices defined in your Environment then choose an instrument. (In our example, we chose the strings channel in our Roland JV1080.) Your menu items will vary, depending on what MIDI modules you own, and how you have them configured in your Environment.
6. To configure the External Instrument with your audio interface input (make sure that you physically connected your MIDI module's audio output to your audio interface's input), click the Input insert area to display a menu of available audio inputs for your audio interface.
You can now record MIDI to the Audio Instrument track. Logic will route MIDI to the external module and will see its audio at the input you defined. You can insert DSP plug-ins and use sends to busses and so on (as with a software instrument). You can also include sounds from External Instruments when you bounce your mix, but keep this in mind: you must perform your bounce in "Realtime," not "Offline," for this to happen. Logic cannot process the audio from an external device offline.