sound barrier, sonic barrier (the sudden increase in drag and other effects experienced by moving objects when their speed approaches that of sound or becomes supersonic)

(film, gaming, music, television, theater) soundtrack (narrow strip running down a movie film that carries the recorded sound in synchronization with the pictures) / (film, gaming, music, television, theater) soundtrack (the sound (especially the music) component of a movie) / (film, gaming, music, television, theater) soundtrack (recording of such music for sale)