Is there Mellotron choir on Afterglow? The main vocal effects at the end are Phil, assembled in the same way as the Voice of Necam by Steve Hackett, Steve's idea to use the computerised faders on the Neve of Croydon Computer Assisted Mixdown (NECAM!) as an instrument.
I guess I was thinking specifically of the Seconds Out version. I could be wrong, but I’m pretty sure it’s mellotron.