Last summer, Esoteric Recordings reissued Principal Edwards’ 1974 album Round One, produced for the band by Pink Floyd’s Nick Mason.  Now the Cherry Red imprint is turning the clock backwards for a 3-CD anthology of precursor group Principal Edwards Magic Theatre.  The Works: Albums, Demos, BBC Sessions and Live Recordings is a comprehensive look at the unusual and large artistic collective (some 17 members over its lifespan) which  indulged in the psychedelic era to create music, mime, theatre, poetry, dance, and even a light show. Formed at Exeter University and named for…