O-4
- Onur Mete
- Onur San
- onwhenready
- Ony Martos
- Onya Gray
- Onyx
- Onyx Colony
- Onyx Creación Divina
- Onze
- Onze:20
- OOFT!
- Oohlas (The)
- Ookay
- Oomhp
- Oomp Camp
- Oomph
- Oomph!
- Oonagh
- ooops
- Oordaya
- OOVEE & Flatdisk
- Oowee
- OP 2
- Op jot Kölsch
- Op zoek naar Nemo
- Opa
- Opa Tsupa
- Opa Unger
- Opanso je ljubiti
- Opérettes
- OPB
- Open (The)
- Open Air Stereo
- Open Hand
- Open Mike Eagle
- Open Minded
- Open the Nile
- Open The Skies
- Open Till L8
- Open Water
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- Opera - Ludwig Is Alive
- Opera De Nuit
- Operación Triunfo 2017
- Operación Triunfo 2018
- Operación Triunfo 2020
- Operación Triunfo 2023
- operacion triunfo 1
- Operation
- Operation Ivy
- Operation M.D. (The)
- Operation Semtex
- Operator Please
- Opeth
- OPFuture
- Ophélie Cassy
- Ophélie Winter
- Ophelia
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- Ophelya
- Ophidian
- Ophiocordyceps
- Opi The Hit Machine
- Opia
- Opiúm
- Opiium
- Opio
- Opium Baby
- Opiuo
- Oplus
- OPM
- Opodeldox
- Opossom
- Oppidan
- Oppnox
- OppositE
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- Optical 2
- Optik Army
- Optikhelden
- Optimale Härte
- Optimo
- Optimus
- Opus Aeterna
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- Opuz
- Oques Grasses
- OR
- OR (O-ERRA)
- Ora Maté
- Oracle
- Oracle Sisters
- Oral Bee
- Oran 'Juice' Jones
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- Orange And Lemon
- Orange Black
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- Orango
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- Oré
- Orba Squara
- Orbit Culture
- Orchestraccia
- Orchestral - The Party Has Just Begun
- Orchestral Manoeuvres In The Dark
- Orchestral Manoeuvres In The Dark (OMD)
- Orchestre Alan Record
- Orchestre Lamoureux
- Orchid
- Orchid Ablaze
- Ordarada
- Ordeal (The)
- Ordeal By Fire
- Orden Ogan
- Order Of Chaos
- Order Of Ennead
- Order Of Era
- Order Of Israfel (The)
- Order Of The Ebon Hand
- Order Of The Fly (The)
- Ordinary Boys (The)
- Ordinary Chill
- Ordinary World
- OrelSan
- Oren Lavie
- Oren Waters
- Orenda Fink
- Oreslan
- Orestes Gomez
- Organ (The)
- Organectomy
- Organiz
- Organized Konfusion
- Organized Noize
- Orgasmic & Fuzati
- Orgasmus & Schwartz
- Orgânico
- Orgi69 & Bass Sultan Hengzt
- Orgie 69
- Orginal Naabtal Duo
- Orgone
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- orhan
- orhan ölmez
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- Orhan Hakalmaz
- Orhan Rexhepi
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- Oriana
- Oriana Leotta
- Oriana.
- Orianthi
- Orielles (The)
- Oriente
- Orietta Berti
- Origami - Larila Song
- Origami Angel
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- Origami Ultra
- Origene
- Original 4 Tiroler Buam
- Original 7ven
- Original Alpenland Quintett
- Original Animals (The)
- Original Banda El Limón
- Original Broadway Cast of Dear Evan Hansen
- Original Cast Vienna
- Original Elias
- Original Flavor
- Original God
- Original H
- Original Kiss
- Original Maintaler
- Original Nielsen Brothers
- Original Sicilian Style
- Original Sistaz
- Originoo Gunn Clappaz
- Oriiginelle
- Orikasa Ai
- Orinda Huta
- Oriol Saltor
- Orioles
- Orion Patrol
- Orion Riders
- Orion Sun
- Orion Too
- Orisha Sound
- Orishas
- Orishas + HeatherHeadley
- Orishas - feat. Heather Headley
- ORβIT
- Orjan Nilsen
- Orkesta Mendoza
- Orla Fallon
- Orla Gartland
- Orlando Brown
- Orlando Dixon
- Orlando Johnson
- Orlando Jordan
- Orlando Riva Sound
- Orlando Vera Cruz
- Orlando Weeks
- Orlane
- Orler
- Orlo
- Orlons (The)
- Orly Chap
- OrMany
- Ormigas
- Ornamentality
- Ornella De Santis
- Ornella Felicetti
- Ornella Tempesta
- Ornella Vanoni
- Ornella Vanoni con Bungaro e Pacifico
- Ornella Zocco
- Ornette
- Oro Bianco
- Oro Ferreira
- Orochi
- Orochi & Dallass
- Orpair
- Orphan, The Poet (The)
- Orpheé
- Orphxn
- Orplid
- Orquesta Aché
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- Orquesta Mayimbe
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- Orquestra e Coro Cid
- Orrin Tucker
- Orry Jackson
- Orsai
- Orslok
- Orson
- Ortal
- Orthanc
- Ortiga
- Ortopilot
- Orus
- Orville Peck
- Orwells (The)
- Oryane Wilson
