Many of of the recording artists that appeared on "Hullabaloo" sang live as opposed to lip sync. Those that sang live or played instruments were often accompanied by pre recorded instrumental and back up vocal tracks, in order to sound as close to the recording as possible. This format began in the 1960s and is still used effectively today.
While the series was in color, in its' 2nd season only, during its original run, only a few episodes have survived in color. All the rest of the episodes, including the first season (Jan. - July 1965) have survived on black and white "kinescopes" (TV images recorded on film). This is because NBC destroyed the tapes in the 1970s once Smith-Hemion Productions turned down the offer to take them into their possession.
George Hamilton, as one time host in 1965, sang The Beatles hit ballad "And I Love Her'. The Producer was so impressed, with his performance, that Hamilton was asked to host regularly, but Hamilton turned it down the offer, as he was not interested in expanding his singing career, at that time.
Producer GarySmith recalls that the bands appearing on the show were often performing on television for the first time. Simon and Garfunkel had not appeared in a television stdio before Hullabaloo.