<P> The Partridge Family's instrumental sound was provided by musicians informally known as The Wrecking Crew, who did many of the pop hits of the day attributed to other performers . The actors pretended to play their instruments . </P> <P> None of the actors sang background; they lip - synched to recorded singing by The Love Generation, AKA The Ron Hicklin Singers, composed of brothers John and Tom Bahler, Jackie Ward (who as Robin Ward had a #14 hit "Wonderful Summer" on Dot Records in 1963), and Ron Hicklin . </P> <P> Actor David Cassidy was originally to lip sync with the rest of the cast, but convinced Farrell that he could sing and was allowed to join the studio ensemble as the lead singer . He and his step - mother, Shirley, are the only two show actors allowed to sing for recording . </P> <P> The Partridge Family theme song, produced by Rogers, was shown over opening credits . More than one song was used as the theme song . Season 1 episodes feature the song "When We're Singin"', which was replaced in subsequent seasons with "C'mon Get Happy". </P>

Who played the father on the partridge family