The Stack Mode Grid is made up of 8 horizontal rows, each divided by 128 lines that correspond to the full range of possible MIDI values.

Up to 8 Parts can be arranged on the STACK MODE Grid as Regions. A Region will always correspond to one Part, and is displayed horizontally along a Row. Once added to the grid, Regions can be moved, resized, or edited using the Mouse.

One Row can contain multiple Part Regions, but each Part can only be present in one Row at a time.
See Adding and Removing Parts.

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