Melvin Bliss recorded "Synthetic Substitution" in 1973 for the small Sunburst Records label. It was a B-side — a throwaway track with no commercial expectations, featuring session drummer Bernard "Pretty" Purdie, one of the most prolific and acclaimed drummers in music history. Purdie's break on the track is raw and punchy, with a heavy snare crack and an aggressive, forward-leaning groove that sounds like it was recorded in a concrete room. The song disappeared almost immediately after release.

The break lay dormant for over a decade until the late 1980s, when Ultramagnetic MCs — featuring a young Kool Keith and producer Ced-Gee — built their groundbreaking track "Ego Trippin'" around it. That single moment of rediscovery opened the floodgates. The "Synthetic Substitution" break became the sound of aggressive, hard-hitting rap production. Its raw, unpolished quality gave it an edge that cleaner breaks couldn't match, and producers reached for it whenever they wanted their tracks to sound tough and uncompromising.

With over 800 documented samples, "Synthetic Substitution" ranks among the most sampled records of all time. It's been used by everyone from Beastie Boys to Dr. Dre, from Gang Starr to Cypress Hill. The break is perhaps the greatest example of boom-bap production's core philosophy: find a hard-hitting drum break, loop it, and let the rhythm do the talking.