Pink Floyd, one of the original electronic "space rock" groups, returned to the Spectrum on Thursday evening with a disappointing show, now only a mere parody of the music medium that they originally created.

The British group, together since 1964, includes Dave Gilmour on guitar, Rick Wright on assorted keyboards, Roger Walters on bass, and Nicky Mason on drums. It was at the vanguard of musical and theatrical innovation during the late 1960s and early 1970s.

Pink Floyd was one of the first groups to use such techniques as light shows, films, fireworks, and quad sound in their stage presentaion. Their last album, "Dark Side of the Moon," released in 1973, was hailed as an artistic and commercial masterpiece and has sold over three million copies, giving the group their present claim to superstar status.

But unfortunetly, in the moret han two years since the group has played Philadelphia, their once magical stage charisma and musical perfection seems to have been lost.

The 1975 Pink Floyd show seems to be little more then going through the motions of creating music. The group has become a media "hype," relying on reputation and expectation to get them through the night.

Sure, the show still retains some nice visual and aural effects, such as an interesting film that coincides with their performance of "Dark Side of the Moon," or use of a 360 degree sound system. But what of the musical content ? Sloppy playing, off-key vocals, poor transitions from song to song, inflectual solos and overuse of gimmicks all combined to make Pink Floyd's performance a deadly bore.

To top it off, the new material from their much-delayed new album, songs such as "Raving and Drooling" and "You Gotta Be Crazy." were plodding, lumbering pieces, relying on form rather than content to carry their gluttonous weight.