There are at least 2 artists named The Blackout:
1) Welsh rock band.
2) Latvian stoner rock/southern metal band.
1) The Blackout are a band formed in 2003 in South Wales and drawing influences from across the board, they combine heavy crunching guitars, riffs, screams and thunderous drumbeats with beautiful melodies and emotionally driven vocals.
The band has played shows in and around the UK with the likes of Lostprophets, Funeral for a Friend