The 1967 version of Casino Royale, starring David Niven, set an unlikely milestone: Its soundtrack album became famous among audio purists for the quality of its sound.

“The legend is that the original master tape had ‘mad’ levels on it,” audiophile Harry Pearson told the New York Times in 1991. “Once the meters pass zero, it means that you’re saturating the tape and running the risk of distortion. On ‘Casino,’ they used a supposedly very fancy grade of tape, and the engineers really pushed it, so the meters were typically running deep into the red — plus one, plus two, plus three, plus four.” The result is an extremely wide dynamic range.

A particular high point is Dusty Springfield’s “The Look of Love” (Track 2). Springfield recorded her vocal in a “tiny isolation booth, so on a really good system, you can hear her voice emerging from what sounds like a little hole in space. She’s not part of the general orchestral acoustic, and once your system gets to a certain point, you can hear that.”

Pearson said the soundtrack came to serve as a benchmark at Absolute Sound, the audiophile bible he founded in 1973. “Whenever we get a piece of equipment that we think is setting new records, out comes ‘Casino,'” he said. “The better your system gets, the more you get out of that album.”

(Thanks, Allen.)