The verse from "Pennies from Heaven," in which both Bing Crosby’s vocals and the orchestral accompaniment were recorded on set (Pennies from Heaven, Major Pictures/Columbia, 1936).

Crosby’s 1936 Decca recording of "Pennies from Heaven."

Awkward transition from dialogue to verse in “The Words are in My Heart.” The orchestral accompaniment was pre-scored and Dick Powell’s dialogue and vocals were recorded on set (Gold Diggers of 1935, Warner Bros., 1935).

Transition from verse to chorus in "The Words are in My Heart," in which the orchestral accompaniment was pre-scored and Powell’s vocals were recorded on set.

Transition from verse to chorus in the second “The Words are in My Heart,” which was recorded after lengthy rehearsal process.

Ginger Rogers’ chorus from "A Fine Romance." Her vocals were recorded on set and the orchestral accompaniment was recorded in postproduction (Swing Time, RKO, 1936).

Astaire’s chorus from "A Fine Romance." His vocals were recorded on set and the orchestral accompaniment was recorded in postproduction.