It's fair to say that Ceremony: An Electric Mass is unlike any other release by an English band normally rooted in the blues. Think of it as Spooky Tooth's version of Concerto for Group and Orchestra by Deep Purple, in which, after two or three promising blues-based rock releases, one member of the band somehow convinces the others to go for a wildly ambitious, experimental concept album. Jon Lord persuaded Deep Purple to dive into the deep end, and Gary Wright convinced Spooky Tooth to welcome acclaimed French composer and musique concrète pioneer Pierre Henry for this electronic mass. Henry's atonal arrangements don't fare too badly against Spooky Tooth's piercing guitars and bluesy wail, although Wright left the band after Ceremony (just as Lord never had the same influence on Purple again, leaving Ritchie Blackmore to lead them on to heavy metal glory).
Credits
Bass Guitar – Andy Leigh
Composed By – Gary Wright, Pierre Henry
Drums – Mike Kellie
Electronics, Directed By [Realisation Sonore] – Pierre Henry
Engineer – Andrew Johns*
Lead Guitar – Luther Grosvenor
Lead Vocals – Mike Harrison (2)
Lead Vocals, Keyboards – Gary Wright
http://www.allmusic.com/album/ceremony-an-electric-mass-mw0000599906