Victory (1984) and Bad (1987), the latter collaboration performed at Hayvenhurst, Jackson's estate in Encino, California. Jackson invited Bottrell to join him producing and composing songs at Ocean Way Studios in Los Angeles in late 1988, but none of the material from several weeks of sessions there made it to the album. In early 1989, the project was moved to Westlake Audio in West Hollywood, and one of the first things Jackson did was to hum the main riff of "Black or White" to Bottrell, who interpreted the tune on guitar, using a Kramer American Series electric guitar plugged into a Mesa Boogie amplifier, miked with a Beyerdynamic M 160. Jackson also suggested the song's rhythm with his voice, and Bottrell programmed this rhythm into an E-mu Systems drum machine. Bottrell augmented the pattern with samples from an Emulator III. His Atari computer ran a MIDI editing program by Hybrid Arts; Bottrell and Brad Buxer used the program to tweak the percussion timings to give more of a swing feel. Jackson recorded his main and backing vocals into a Neumann U47 microphone. Bottrell said that throughout the next 18 months of changes to the song, Jackson's initial scratch vocal was left in place, and it appears on the final version. After two days of work, the song had vocals, drum sounds and electric guitar. Bottrell added an acoustic guitar part using a Gibson LG-2 built in the 1940s; a robust model with a big country sound reminiscent of Gene Vincent's classic rockabilly style. Jackson became busy working on other projects, and "Black or White" languished for a few months. The song was picked up again when Bottrell's part of the album project moved to Record One in Sherman Oaks. Bottrell and Jackson felt that the song had two big gaps in the middle, and they determined to fill them. Jackson wanted a heavy metal guitar to fill one of the gaps, so he sang the part he wanted, including chord arpeggiations, to session player Tim Pierce who performed it on a Les Paul instrument plugged into a Marshall stack. Michael Boddicker added the sound of a high-speed guitar by using a Roland sequencer, assisted by Kevin Gilbert. Bottrell blended two different bass sounds, primarily Bryan Loren playing a Moog keyboard bass, augmented by Terry Jackson playing an electric bass guitar. (Terry Jackson was unrelated to Michael Jackson. Terry was discovered