Remixing "4'33"" — John Cage's famously silent composition — sounds like an easy music student joke, but someone took the idea seriously and actually came up with a pretty great result.

A John Cage piece for organ titled ASLSP — as slow as possible — lives up to its name. It has been in performance for 21 years so far.

“I’m 99 percent sure that John Cage, if he’s sitting on a cloud somewhere, would say, ‘Oh, it's good,’” Neugebauer tells NPR. “He would laugh about the mistakes we’ve made.” ...

Entitled “As Slow as Possible” (ASLSP), the composition by the late American composer John Cage is due to be played out over 639 years at the St. Burchardi church in Halberstadt in Germany.