Okay, so we're taking liberties including Frank Zappa in this prog-rock installment of Riff Box, but we just couldn't help it. After all, it's silly to deny that Zappa is progressive. From the outset, his albums have pushed the musical envelope, bursting with odd-time signatures, rapid tempo and style transitions, startling contrasts in dynamic intensities, unorthodox instrumentation, and, of course, top-drawer musicianship, all in an "everything-but-the-kitchen-sink" fusion of musical styles.
Zappa's guitar soloing was as inventive as his music and has been described in such contrasting terms as: frenzied yet in control, frighteningly beautiful, logically chaotic, and melodically cacophonous.
"Cosmik Debris," from 1974's Apostrophe ('), features a straightforward, bluesy riff that serves as the launching pad
for several themes introduced throughout the song [Fig. 6].