| Obscurum | 0 | 0 |
| Obsequial Sceptre | 0 | 0 |
| Observation Room | 0 | 0 |
| Obsimo | 0 | 0 |
| Obukhovaudio | 0 | 0 |
| Obviousgod | 0 | 0 |
| Ocaso | 0 | 0 |
| Occams Laser | 0 | 0 |
| Ocean Districts | 0 | 0 |
| OceanLab | 1 | 0 |
| Oceanographer | 0 | 0 |
| Ocho | 0 | 0 |
| Ocrilim | 0 | 0 |
| Octa Möbius Sheffner | 5 | 0 |
| Octav Enigărescu | 0 | 0 |
| Octavepussy | 6 | 0 |
| Octavi Rumbau | 0 | 0 |
| Octavie Dostaler-Lalonde | 0 | 0 |
| Octavio Arevalo | 2 | 0 |
| Octavio Vázquez | 0 | 0 |
| October | 0 | 0 |
| Octodred | 0 | 0 |
| Octophoros | 0 | 0 |
| Octuor à Vent de Paris | 0 | 0 |
| Octuor à vents Nepomuk | 0 | 0 |
| Oculi Ensemble | 0 | 0 |
| Odair Assad | 0 | 0 |
| Odaline de la Martínez | 0 | 0 |
| Odd Grüner-Hegge | 0 | 0 |
| Odd Nordstoga | 0 | 0 |
| Odd Nosdam | 20 | 0 |
| Odd Panda | 0 | 0 |
| Oddateee | 0 | 0 |
| Oddrun Lilja Jonsdottir | 0 | 0 |
| Odds | 7 | 0 |
| Oded Tzur | 0 | 0 |
| Odekhiren Amaize | 2 | 0 |
| Odell Aumere | 0 | 0 |
| Oden & Fatzo | 1 | 0 |
| Odense Symfoniorkester | 21 | 0 |
| Odeon Quartet | 0 | 0 |
| Odeon Trio | 4 | 0 |
| Odessa Philharmonic Orchestra | 0 | 0 |
| Odessey & Oracle | 0 | 0 |
| Odetari | 6 | 0 |
| Odete Amaral | 0 | 0 |
| Odette | 0 | 0 |
| Odette Chaynes-Decaux | 1 | 0 |
| Odette Ernest Dias | 0 | 0 |
| Odette Lara | 0 | 0 |
| Odette Myrtil | 0 | 0 |
| Odetto | 0 | 0 |
| Odhecaton | 0 | 0 |
| Odile Bailleux | 1 | 0 |
| Odile Delangle | 3 | 0 |
| Odile Edouard | 0 | 0 |
| Odile Pierre | 8 | 0 |
| Odious Spirit | 0 | 0 |
| Odonis Odonis | 0 | 0 |
| Oduvaldo Vianna Filho | 0 | 0 |
| Odyssean Ensemble | 0 | 0 |
| Odyssey Opera | 0 | 0 |
| Odyssey Opera Chorus | 0 | 0 |
| Odyssey Opera Orchestra | 0 | 0 |
| Odyssey Orchestra | 0 | 0 |
| Odón Alonso | 0 | 0 |
| Of Virtue | 0 | 0 |
| Ofelia K | 3 | 0 |
| Ofelia Sala | 2 | 0 |
| Ofenbach | 1 | 0 |
| Offenburger Streichtrio | 0 | 0 |
| Offernat | 0 | 0 |
| Officers | 1 | 0 |
| Officina Musicale | 0 | 0 |
| Oficina Musicum | 0 | 0 |
| Oforia | 0 | 0 |
| Ofra Harnoy | 22 | 0 |
| Ofri Nehemya | 0 | 0 |
| Ofé | 0 | 0 |
| OgLounis | 0 | 0 |
| Ogi | 0 | 0 |
| Ogryzek | 0 | 0 |
| Oh Boy | 1 | 0 |
| Oh He Dead | 0 | 0 |
| OhGeesy | 0 | 0 |
| Ohad Ben-Ari | 0 | 0 |
| Ohad Talmor | 8 | 0 |
| Ohbliv | 0 | 0 |
| Ohio Light Opera Orchestra | 0 | 0 |
| Ohio State Concert Band | 0 | 0 |
| Oi-SKALL Mates | 0 | 0 |
| Oily Rags | 0 | 0 |
| Ois Yanur | 0 | 0 |
| Oisel | 0 | 0 |
| Oisin Mod | 0 | 0 |
| Ojas Adhiya | 0 | 0 |
| OkayKayo | 0 | 0 |
| Okka von der Damerau | 0 | 0 |
| Okko Kamu | 42 | 0 |
| Oklahoma City Philharmonic | 0 | 0 |