Tegan and Sara's ever-broadening pop sound translates well to a big stage like the one at Jimmy Kimmel Live, where the Canadian group last night performed the single "Closer" from their new album Heartthrob, which Rolling Stone premiered last month. A pulsing beat propelled the synth-y song as the Quin sisters sang a song that Tegan last year told Rolling Stone is about "a time before sex, complicated relationships, drama and heartbreak."