the pomona valley symphony

The Pomona Valley Symphony Orechestra, conducted by Fred E.Graff, plus a rock 'n' roll combo played they score to "The World's Greatest Sinner" of which the music was written by Frank Zappa.

info from Ben Watson:
Another involvement was music for a film called "The World's Greatest Sinner", a vehicle for Tim Carey.
Zappa's score was played in 1960 by amateurs and semi-professionals gathered together by the music teacher at pomona high school: fifty-two musicians, two microphones, mixed down to mono in a mobile studio in a truck outside the Chaffey College little theater. The credit ran: The Pomona Valley Symphony Orchestra conducted by Fred E. Graff. For the rock 'n' roll sections Zappa played guitar, Kenny Burgen saxophone, Doug Rost rhythm guitar and Al Surratt drums. 'Rancid' was Zappa's description of the recording conditions.

info from Paul Buff:
To my recollection, the "Run Home Slow" soundtrack did not use the Pomona Valley Symphony - they were Hollywood studio musicians, I believe. I did the recording at Original Sound, with Zappa producing and directing.