Realistically, this collaboration probably should have happened a long time ago. And apparently it would have if Karen O had her way. The Yeah Yeah Yeahs fronter reportedly pitched superstar producer Danger Mouse on the idea more than a decade ago. But it took them this long to get it together — not surprisingly, given that the producer born Brian Burton is a member of Broken Bells and Gnarls Barkley in addition to his studio work with everyone from The Black Keys and Portugal. The Man to Adele and U2. Thankfully, the artful and ambitious Lux Prima is more than worth the wait. As expected, O brings her edgy yet tender vocals, introspective lyrics and indie-rock sensibilities to the table, and Burton supplies his lush arrangements, slow-jam grooves and dusty psychedelia. The time-travelling results allow both parties to play to their strengths. Burton gets to stretch out on stylishly sprawling cuts like the trip-hoppy opening title track and the avant-pop closer Nox Lumina. Between them, groovy ’60s-inspired numbers like Turn the Light, Woman and Redeemer satisfy the alt-rock and pop quotient. So everybody goes home happy. And we just have to hope they don’t keep us waiting another decade for a rematch.