The Three Little Bops (1957) by Friz Freleng

Instrument credits are believed to be:
Vocals - Stan Freberg (credited on the short)
Saxophone - Pepper Adams (or possibly Jimmy Giuffre)
Trumpet/flugelhorn - Shorty Rogers (credited on the short)
Piano - Pete Jolly
Guitar - Barney Kessel
Bass - Red Callender (or possibly Red Mitchell)
Drums - Stan Levey (or possibly Shelly Manne)

This is the only Warner Brothers cartoon to not feature Mel Blanc doing voice characterizations during the period of Blanc's exclusive contract with the studio. It is also one of only three from that time frame that gives a voice credit to anyone other than Blanc (the others were The Mouse that Jack Built, which credits the cast of The Jack Benny Program, of which Blanc was a cast member and thus was credited accordingly, and The Unmentionables, which credits Blanc and Ralph James). Although Freberg, among others, had contributed voices to Warner Brothers cartoons during this time, none of them were credited.