2001 (Dr. Dre album) were later cut from the final track list. The tracks have been leaked later on several mixtapes, including "Pretox". The album's production expanded on that of "The Chronic", with new, sparse beats and reduced use of samples which were prominent on his debut album. Co-producer Scott Storch talked of how Dr. Dre used his collaborators during recording sessions: "At the time, I saw Dr. Dre desperately needed something. He needed a fuel injection, and Dre utilized me as the nitrous oxide. He threw me into the mix, and I sort of tapped on a new flavor with my whole piano
Dr. Dre popular music, having been used in over 1700 songs. From "Straight Outta Compton" on, Dre uses live musicians to replay old melodies rather than sampling them. With Ruthless Records, collaborators included guitarist Mike "Crazy Neck" Sims, multi-instrumentalist Colin Wolfe, DJ Yella and sound engineer Donovan "The Dirt Biker" Sound. Dre is receptive of new ideas from other producers, one example being his fruitful collaboration with Above the Law's producer Cold 187um while at Ruthless. Cold 187 um was at the time experimenting with 1970s P-Funk samples (Parliament, Funkadelic, Bootsy Collins, George Clinton etc.), that Dre also utilized. Dre has since