Sound first — cuts without pauses
A new Sound first transition: the next clip's sound starts before the picture changes, so a cut never lands in a pause. AI editing adds it on its own.
A new Sound first transition
This is how professional editors cut speech: the next clip's sound starts a split second earlier, the previous picture holds a moment longer and changes on the first words of the new sentence. The cut never lands in a pause, the speech flows evenly, and the picture change is barely noticeable.
Sound first is the first tile in the Transition panel and in the Library. Its duration is how far the picture lags behind the sound: 0.3 s, 0.5 s (default), 0.65 s or 0.8 s. The cut shows up in the preview right away — on the web and in the app.
AI editing adds it on its own
At speech cuts where the picture visibly changes — another take, another source — Slicer adds Sound first on its own and picks the lag by the first word of the new clip. Where an abrupt cut is the point, the director keeps a straight cut. You can remove or change any of these cuts like a regular transition.
API and MCP
The tune_block and set_all_transitions operations accept a new jcut transition kind with a duration from 0.15 to
1 s.