Singer Paul Weller opened the inaugural BBC Electric Proms on Wednesday, along with Jamiroquai and The Magic Numbers.
Weller headlined the evening at the Roundhouse in north London
The Who will perform their rock opera Wire And Glass for the first time during the five-day music festival, in venues around Camden, north London.
All 68 artists involved have been asked to come up with something "innovative" for their performances.
Event highlights - inspired by the classical Proms - are being broadcast on radio, television and online.
The Klaxons and The Young Knives also performed on Wednesday evening.
Weller was joined on stage by Amy Winehouse for a cover of Marvin Gaye's I Heard It Through The Grapevine, while Dirty Pretty Things singer Carl Barat and Hard-Fi's Richard Archer also took to the stage to perform Jam tracks.
Guillemots will perform with Kasabian and the BBC Concert Orchestra
The headline performances can be seen on the BBC Electric Proms website.
Gorillaz and Blur frontman Damon Albarn is lined up to perform with his latest project, The Good, The Bad and the Queen, on Thursday.
Albarn's new band features ex-Clash bassist Paul Simonon, Tony Allen of Fela Kuti and Simon Tong from the Verve.
Fatboy Slim is set to play an intimate gig for 100 fans at the Lock Tavern pub on Friday.
On Saturday, the Mercury Prize nominees Guillemots will perform with the BBC Concert Orchestra in a bid to create a "unique musical collaboration".
James Brown, The Zutons and Billy Bragg are just some of the other big names who are taking part.
Festival director Lorna Clarke said: "Our ambition is to stage an event that will create new musical moments".
The festival also includes film screenings, art and master classes.