the holographic effect is a phantom audio illusion that occurs in recorded music especially when the medium used is magnetic tape, and the electronic equipment used has mostly vacuum-tube-based audio circuitry. the era during which these two factors were largely in place, and when one had the greatest possibility of experiencing the effect, was during the late 1950s/early 60s. hearing it gives you the creeps, as if the tape is actually possessed by an entity, or ghost-copy of the musicians. you're not just hearing a song, you're "watching audio". your brain connects pathways that haven't been used for listening to music, perhaps ever.