Wallace Roney, Saturday, August 12, at the Bluebird Theater, came to the public's attention in 1981. Then a 21-year-old Berklee student with no trumpet of his own, he auditioned for Wynton Marsalis's old seat in Art Blakey's Jazz Messengers, armed with little more than ambition and talent. But that was enough: He got the gig, and after Marsalis returned to Blakey's group for a time, Roney remained. By 1983, Miles Davis was so impressed with Roney that he gave him a trumpet--and passed along a second instrument when the rising star joined him on stage at the 1991 Montreux Jazz Festival (Davis's last public performance). It was only natural, then, that Roney signed on as point man for the "Tribute to Miles Davis" tour featuring Davis alum Tony Williams, who has been quoted as saying, "Wallace, like Miles, is always on the edge of a mistake. He plays more music than he does trumpet." Today, with eight albums behind him, Roney is finally stepping out of Davis's shadow. Similarities remain, but Roney's horn makes its own unique sound.