The Cultural Heritage Index estimates that there are 46 million magnetic tapes in museums and archives in the U.S. alone—and about 40 percent of them are of unknown quality. (The remaining 60 percent are known to be either already disintegrated or in good enough condition to be played.)  

What’s more, in only about 20 years we won’t be able to digitize them, according to audio and video preservationist George Blood, in Philadelphia. This is partly because digitization machines that can handle the tapes have ceased production. On Sept 30th, for example, Sony stopped taking orders for videotape machines, and in June 2015, the last audio reel-to-reel machine went out of production. Plus, the ones that already exist are wearing down—and parts to repair them are difficult to come by. And to add to this, the tapes themselves are degrading. Trying to digitally process these in studio-grade machines, for example, clogs the tape player heads, wrecking the very machinery that can digitize the tapes as stocks of them are dwindling.