Preparation now bakes the sine beds, harmonies, music box, pad and percussion into each seat's stem (approximated on the Mac), so nothing on a seat is fired from a simulation frame: the deck plays it all sample-locked from the downbeat. The plan marks those events baked and native staging keeps them off the live list; the notation still shows them. measure-sync.py samples every seat's audio clock against the wall clock while a piece plays: rate, jitter, seat-to-seat spread. Staging accepts seats showing the stock spatial-rehearsal or notespatial-controls pieces. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>