Terry Riley, A Rainbow in Curved Air (side A)

I had always assumed that Riley sequenced analog synthesizers on 1969's A Rainbow in Curved Air.  I surprised myself when I looked at the back cover and saw the list of keyboards used on "A Rainbow in Curved Air".  On listening back, I could recognize both the electric harpischord and RMI Rock-si-chord when they jumped loudly out of the mix.  I'm now amazed by how accurately Riley played the layered sequences.  The electric harpsichord sounds more distorted than similar instruments on songs like "Because" and "Burning the Midnight Lamp" — it's not clear to me how it was recorded or whether this was on purpose.  The sparkly detailed tambourine also sounds especially remarkable.  Riley's soprano saxophone playing on side B also sounds amazingly like a synth — it directly foreshadows much of Jon Gibson's work.  The front cover collage design looks dated, and it also does not closely relate to the music.