By 1996, Dre was again looking to innovate his sound. He recruited keyboardist Camara Kambon to play the keys on "Been There, Done That", and through Bud'da and Sam Sneed he was introduced to fellow Pittsburgh native Melvin "Mel-Man" Bradford. At this time, he also switched from using the E-mu SP-1200 to the Akai MPC3000 drum kit and sampler, which he still uses today. Beginning with his 1996 compilation Dr. Dre Presents the Aftermath, Dre's production has taken a less sample-based approach, with loud, layered snare drums dominating the mix, while synthesizers are still omnipresent. In his critically acclaimed second album, 2001, live instrumentation takes the place of sampling, a famous example being "The Next Episode", in which keyboardist Camara Kambon re-played live the main melody from David McCallum's 1967 jazz-funk work "The Edge". For every song on "2001", Dre had a keyboardist, guitarist and bassist create the basic parts of the beat, while he himself programmed the drums, did the sequencing and overdubbing and added sound effects, and later mixed the songs. During this period, Dre's signature "west coast whistle" riffs are still present albeit in a lower pitch, as in "Light Speed", "Housewife", "Some L.A. Niggaz" and Eminem's "Guilty Conscience" hook. The sound of "2001" had tremendous influence on hip-hop production, redefining the West Coast's sound and expanding the G-funk of the early 1990s. To produce the album, Dre and Mel-Man relied on the talents of Scott Storch and Camara Kambon on the keys, Mike Elizondo and Colin Wolfe on bass guitar, Sean Cruse on lead guitar and sound engineers Richard "Segal" Huredia and Mauricio "Veto" Iragorri.