Oceanaires Barbershop Chorus - SPEBSQSA chapter from Santa Monica, California. Information on membership, shows and events. oceanaires.org
Oklahoma Music Central - Barbershop Chorus from Oklahoma City, Oklahoma. music-central-ok.org/music.html
Old Capitol Chorus - Composed of male voices of all ages and interests who sing the a cappella style barbershop. From Iowa City, Iowa. soli.inav.net/~baritone
Orange Blossom Chorus - Performing chorus of the Orlando chapter of the Society for the Preservation and Encouragement of Barbershop Quartet Singing in America, Inc. home.cfl.rr.com/bjstock/obc.htm
Overland Stage Chorus - Male barbershop chorus from Overland Park, Kansas. www.overlandstage.org
