Legacy instruments in MainStage
The legacy instruments are less CPU- and memory-intensive versions of equivalent MainStage instruments. All legacy instruments feature a few carefully chosen parameters that provide maximum impact and flexibility, making it easy to create great sounds.
Legacy instruments are automatically loaded when you open a GarageBand project, a Logic Pro project, or a MainStage concert that uses one or more of these instruments.
You can use these plug-ins or you can replace them with other instrument plug-ins available in MainStage.
You cannot directly insert these plug-ins in MainStage unless you override the Instruments plug-in menu.
If you’re new to using plug-ins in MainStage, see Add and remove plug-ins in MainStage.
Display and insert legacy instrument plug-ins in MainStage
In MainStage, press Option, then click the Instrument slot on a channel strip.
The plug-in menu opens, with a Legacy submenu shown below Vintage Mellotron.
Choose the legacy instrument plug-in that you want to insert from the Legacy submenu.