This video, via Cuneiform Records, captures a lost interview with seminal minimalist composer Terry Riley.

Riley’s pioneering electro-acoustic music of the 1960’s explored combining tape delay with electronic and acoustic instruments to create feedback loops that allowed live layering of sounds.

His hypnotic 1969 album, A Rainbow In Curved Air, influenced musicians like Pete Townshend of The Who and classical composers like Steve Reich alike. Hearing the album now, it’s easy to appreciate how it blew people’s minds in the 60’s and has an influence that extends all the way to modern electronic music.

The 2005 Henry Kaiser interview was recorded for a DVD that was never released of Riley’s 1969 multimedia project with sculptor Arlo Acton, Music With Balls, embedded below:

Music With Balls was first televised on KQED in April 1969. It was a synthesis of abstract visuals, featuring Arlo Acton’s spherical sculptures of glittering titanium, and a soundtrack on which Terry Riley played hypnotically repetitive music using the feedback from two tape machines.

The interview is unedited, so it’s a little raw, but it offers a unique example of Riley discussing his process and demoing his approach, a style that has inspired other electronic musicians for 50 years.