"Rapper" is a term that doesn't quite fit Robert Williams, the talented Philadelphia MC who performs as Meek Mill. He is a barker, a bellower – an heir to the tradition of Ice Cube, unloading his rhymes in a rat-a-tat staccato assault, at maximum volume. Listeners who know Meek from his Dreamchasers mixtapes and scene-stealing cameos on Maybach Music compilations will recognize the character in the title track on his major-label debut: a braggart with a chip on his shoulder and a knack for stacking up nifty interior rhymes. ("Did it without an album/I did shit with Mariah/Little nigga, I'm on fire/Icy as a hockey rink, Philly nigga, I'm Flyer.") In hits like the Drake collaboration "Amen," Meek cleverly tweaks sex-rap clichés. But on Dreams and Nightmares he mostly keeps things gritty, telling – that is, yelling – hardscrabble street stories, in a voice big and brassy enough to be heard 20 blocks away.

Listen to 'Dreams and Nightmares'

“Help Me”

Joni Mitchell wrote and recorded this song for her album Court and Spark, but she had to switch from her regular band to make the song sound exactly the way she wanted. "I had attempted to play my music with rock & roll players," she told Rolling Stone. "They’d laugh, 'Awww, isn't that cute? She's trying to teach us how to play.'" Mitchell switched to a jazz band, Tom Scott’s L.A. Express, and scored the biggest hit of her career in the process.