Noah And The Whale performing at the LA Weekly Detour Music Festival
Noah & The Whale, Ladyhawke and Damien Rice have been added to this year's Mencap Little Noise Sessions.
Duke Spirit and Dan Black & Skint & Demoralised also join the line-up for the Union Chapel shows.
They join Kasabian, Razorlight, Stereophonics, Glasvegas, Keane, James Morrison and The Fratellis for the charity gigs which take place from 8-18 November.
This is the third year the event has been held.
Damien Rice joins Adele's intimate gig on 11 November while Duke Spirit have been added to Seasick Steve and Stereophonics the day before.
Skint and Demoralized will appear on the Razorlight night on 9 November and Dan Black will join James Morrison and Katy Perry on the 13.
Noah and the Whale and Ladyhawke, will celebrate the end of this year's Little Noise Sessions with The Fratellis and Sergeant on 18 November.
As with previous sessions, which saw impromptu appearances from U2 and Coldplay, a number of surprise guests will also be performing this year.
In the past, Amy Winehouse, Noel Gallagher, Snow Patrol, Duffy and Lily Allen have performed at the event.
Tickets are available from Mencap's official site.