It is highly recommended that you test your concert thoroughly using the same setup you plan to use in live performance prior to performing, at the performance location or venue if possible. This is especially important for more complex hardware setups.
If you plan to use multiple keyboard controllers when you perform, you can choose whether screen controls respond to MIDI messages from all controllers or only a specific controller and whether channel strips receive input from all controllers or only a single controller.
In Layout mode, screen controls can be set to respond to MIDI input on all MIDI ports and channels or to only a specific device or channel. To have a screen control respond to MIDI input from all controllers, choose All from both the Device and Channel pop-up menus in the Layout Inspector. To have a screen control respond to a specific controller or to the same channel as the keyboard screen control, choose that controller from the Device pop-up menu.
In Edit mode, you set the device from which a channel strip receives MIDI input in the Key Range section of the Channel Strip Inspector. By default, channel strips receive input from the first controller in the layout. You can set a channel strip to receive input from another device in the Input pop-up menu.
If you use MainStage with a complex hardware setup, for example, with multiple MIDI controllers or MIDI interfaces or with multiple audio inputs, you will achieve the best results when you use exactly the same hardware setup you used when you created your concert.
If you plan to use MainStage with different controllers, interfaces, or other devices than the ones you used to create your concert, you need to relearn your hardware assignments using your performance hardware setup. To facilitate working in this situation, you can create two separate layouts, one for your studio setup and another for your performance setup, with corresponding screen controls in each layout. Before you perform, import the performance layout into your concert. The hardware assignments for your performance setup are imported with the layout, and your mappings are maintained.