Nevertheless, the film abounds in interesting details of the intermingling of sound, image, and music. I wrote about one of those yesterday ("nondiegetic-offscreen"). Here are two additional examples of the treatment of sound early in the film.
The long scene in which Mozart is introduced to the Emperor (and embarrasses Salieri for the first time) runs from about 00:26:00 to 00:36:34. At the end of this, making the cut at the end of the scene, director Milos Forman manages a simple but very effective match that juxtaposes Mozart in medium closeup, looking left and uttering his hyena-laugh, with Salieri, also in medium closeup, looking right, silent, and bitterly angry. A bit less than three minutes later, a female student is vocalizing as Salieri plays, then cut to the stage with the student singing the same figure as part of an aria in Mozart's opera Abduction from the Seraglio (with Mozart conducting). The sound match is as direct as could be and would make an excellent first example for the sound match as applied to music.
Almost immediately thereafter, a neatly symmetrical pairing illustrates onscreen/offscreen sound. The elderly Salieri talks (still to the priest) about how Mozart's triumph (and apparent stealing away of the soprano's affections) upsets him. At about 00:39:35, Salieri is speaking but the stage music continues offscreen (at a reduced volume). Then (or at about 00:39:40) the reverse happens: we see the stage (and hear music) but Salieri is heard speaking at normal volume in voiceover narration. The aria ends at 00:40:40.
