Imagine a painting. The stereo master is the finished canvas hanging in a museum. The multitrack master is the pile of 24 individual transparencies—each containing just the drums, just the bass, just the backing vocals, or just the cough at the end of the fourth take.

Located in a secretive, unmarked facility (rumored to be in New Jersey), the vault is a concrete bunker designed to survive everything short of a nuclear blast. The interior is kept at a strict —the golden standard for polyester tape longevity.

Under the leadership of Jody Klein (son of legendary manager Allen Klein), ABKCO has amassed a collection that rivals that of the Library of Congress. While Universal Music Group holds massive archive, the largest multitrack music collection ever assembled in one contiguous, climate-controlled space is widely believed to belong to this independent entity.

Because these tapes allow for remixing, surround sound upmixes, noise reduction, and the rescue of damaged recordings. Without the multitrack, history is locked in amber. With it, history breathes again. The Collector: The Man Behind the Tapes The architect of this monumental archive is Jody Klein (though depending on recent acquisitions, similar claims are made by the Iron Mountain Entertainment Services vault and private collector Glenn Korman —but for the purpose of this deep dive, we are focusing on the largest singular coherent collection recognized by industry archivists: the ABKCO Music & Records vault ).

(Boyers, Pennsylvania) claims to house over 20 million assets, including the masters for Sony Music, Universal, and Warner. However, those are storage clients —they do not own the collection. ABKCO owns theirs.