Turn on your radio. Hear that voice, a feathery tenor with a hint of soulful grit? It belongs to Bruno Mars, the 25-year-old Hawaiian newcomer featured on smash hits like B.o.B’s “Nothin’ on You” and Travie McCoy’s “Billionaire.” Doo-Wops & Hooligans proves that Mars is a natural — a lavishly gifted melodist (check the surging “Grenade”) and an engaging singer. It’s the year’s finest pop debut: 10 near-perfect songs that move from power ballads to bedroom anthems to pop-reggae and deliver pleasure without pretension. Call it bubblegum that eats like a meal.