Sandoval said that even major artists of the era, like the Kinks, have very few of their early multis. “You’re never going to hear alternate takes of classics like ‘You Really Got Me’ or ‘All of the Day,’” he said. “None of those things exist.”

During the 1970s and ’80s, multitracks were haphazardly stored, organized and prized, even by major labels. It wasn’t uncommon to walk into a place like Coast Recording Equipment Supply, a pro audio shop in Hollywood, and find used reels being sold for recording that contained multitrack masters by bands like the Doors.

It wasn’t until the CD era and the explosion of deep-dive compilations and boxed sets in the late ’80s and early ’90s that record companies started to fully realize the value of their multitracks. “When you get into the re-marketing of music and creating reissues, the first thing a label asks is: ‘Is there something new here?’” Sandoval said. “In order to find or create something new, you usually need to go back to the multitracks — that’s your biggest source of alternate takes, outtakes and unreleased material.”

Today, multitracks arguably hold even more value thanks to the rise of remix projects, the development of immersive audio formats like Dolby Atmos, and even TV, film and commercial sync opportunities, which often require use of the original recording elements.

“The ability to recast an artist’s music, to present it in a new way, usually depends on the multitracks,” said John Jackson, the longtime Sony/Legacy A&R executive. Now running his own consultancy, advising Billy Joel, Rosanne Cash and the estate of AC/DC’s Bon Scott, he noted that “if you don’t have the multitracks or have a plan for the multitracks, you’re not recognizing and celebrating the value of that artist’s music fully.”

THERE’S NO QUESTION that the vagaries of the music business have claimed plenty of important recordings over the years.