“Departure” is the first cut from the 1969 Moody Blues album “In Search of the Lost Chord.”
I am curious to know if the long slow upward glissando is played on a theremin; and if so, what kind of theremin it was.
While it sounds LIKE a theremin, it does not sound like any of the theremins that would have been available when the record was done in 1968 — none that I know of, anyway. It is a very pungent, intense sound, not “reedy” like an RCA nor “sinewavey” like the various kit theremins available at that time.
It does seem to be somewhat processed with some sort of effects pedal. When you listen to it, you’ll hear what I mean.
Note that the track does end as abruptly as this sample and then it segues immediately into the 2nd track on the album, “Ride My See-Saw.”