Drag the amber handles, or drag across the screen to set a new range. Click the ruler to play from a point. Audio left of the REC mark is pre-roll from the buffer — pull the start handle back into it.

Click a region to select & audition · double-click to add a slice · drag a blue marker to move it · alt-click or double-click a marker to delete · press K while playing to chop live.

Stretch changes time and pitch independently (WSOLA). Tape links them like varispeed. Markers move with the audio, and BPM / key metadata are updated. Undo with ⌘Z.