lost recordings

Lost recordings are audio or video recordings believed to exist but currently unavailable—destroyed, misplaced, or held in inaccessible archives.

The term carries a sense of cultural tragedy, suggesting valuable artistic work that may never be heard or seen again: Researchers discovered lost recordings of the composer's early concerts.

Some lost recordings are merely rumored to exist; others are confirmed but physically missing.

The phrase often appears in music journalism when previously unavailable material surfaces: The label is releasing lost recordings from the 1972 sessions.