He bought his first guitar at the age of 9. At 12, he toured with the Allman Brothers Band, and at 15, formed his own outfit, the The Derek Trucks Band. A prodigy? Rolling Stone magazine thought so, making Derek Trucks the youngest musician awarded that distinction in its list of the 100 greatest guitarists of all time. No surprise, then, when he packed the Spectrum in 2007. Now 30, the slide guitarist-also notable for his play with Clapton-and a band of musicians inspired by improvisational play, explore progressive roots music blending blues, soul, jazz and different strains of world music on his latest album, Already Free.