Event-driven sync lets a concurrent voice block on a named cue and be woken by a broadcast — distinct from time-grid quantization

Event-driven sync (ChucK Event+signal/broadcast, Sonic Pi cue/sync) is a mechanism for coordinating concurrent voices via named messages rather than shared time grids. A voice blocks on a named cue and resumes when another voice broadcasts that cue. This is message/barrier sync between concurrent voices — fundamentally different from clock-quantized launch (which aligns voices to a shared time grid) and from cyclic/graph patterns (which have no equivalent). It allows one voice to trigger another’s transition at a musically meaningful moment (e.g., ‘start the breakdown when the build reaches its peak’) rather than at a fixed time-grid boundary.

Examples

Sonic Pi: in_thread { cue :drop }; in_thread { sync :drop; play_drop_pattern }. The second thread waits for the cue regardless of when the first fires it.

Assessment

Describe the difference between clock-quantized launch and event-driven sync. Give a musical scenario where event-driven sync is more appropriate than time-grid quantization.