Otep
death metal, metal, nu metal
Otherwise
alternative metal, alternative rock, hard rock, post-grunge, rock
Otis Blackwell
blues, rhythm and blues, rock and roll, singer-songwriter, soul
Otis Gibbs
americana, bluegrass, folk
Otis Redding
blues, oldies, rhythm and blues, soul
Otis Redding & Carla Thomas
funk, rhythm and blues, soul
Otis Rush
blues, chicago blues, electric blues
Otis Spann
blues, delta blues, piano blues
Otis Taylor
blues, rock, singer-songwriter, folk
OTT
ambient, chillout, dub, electronic
Otto Knows
dance, house, progressive house
Our Daughter's Wedding
new wave, synthpop, technopop
Our Last Night
emo, emocore, post-hardcore, screamo
Our Waking Hour
alternative metal, alternative rock, modern rock, rock
Ours
alternative rock, indie rock, rock
Out of Focus
krautrock, progressive rock, psychedelic rock
Outlaws
classic rock, country, country rock, rock, southern rock
Outrage
straight edge, thrash metal
Ovens
indie pop, indie rock, power pop