was working on his collaboration album Watch the Throne (2011) with Kanye West. There they created a "primitive studio" using a microphone, a rig out and Pro Tools software to record. Sessions were also held in Las Vegas, Los Angeles, Atlanta and Honolulu. In February 2011, MTV reported the project was nearing completion. 4 was mixed mostly at MixStar Studios in Virginia and mastered at Sterling Sound in New York City. The audio mastering was delayed by a week following the unexpected recording of "I Was Here". Diane Warren had played the song to Jay-Z during a telephone conversation, leading him to put Warren and Beyoncé in contact. In May 2011, Beyoncé submitted seventy-two songs in preparation for the album's release. According to Swivel, an eclectic range of songs were recorded, including ballads, "weird ethereal things" and 1990s R&B and Afrobeat-inspired songs. Music and lyrics The final cut of 4 comprises twelve tracks on the standard edition and eighteen on the deluxe edition—three of which are remixes of "Run the World (Girls)". Critics viewed 4 as a major departure from Beyoncé's previous catalogue, with a distinctive mellower sound. The album consists mostly of mid-tempo R&B songs, with 1970s funk, 1980s pop and 1990s soul influences. The second half was more eclectic, exploring a variety of genres including hard rock, reggae and adult contemporary. The Guardian complimented the album's divergence from the "layering [of] Euro-synths on pop-step woomphs" that characterize the music of Beyoncé's contemporaries. The balladry of the first half of 4 combines diverse vocal styles with the use of live instrumentation. "1+1" demonstrates Beyoncé's vocal-flexing over "magnificent guitar bombast" and a soft backing beat, while "Start Over", a mid tempo R&B ballad, uses a futuristic beat with electric elements and synthesizers. "I Miss You", with its "layers of atmospheric keyboards", ambient synthesizers and tinny 808 drums was sung in a half-whisper to exhibit intense emotion. "I Was Here", an understated pop-R&B ballad with indie rock inflections, primarily concerns self-reflection with dramatic vocals. On other songs, Beyoncé explores womanhood. "Best Thing I Never Had", 4s fourth track, was described as a moment of self-realization and a "female call to arms". With vocals that allude to a "wounded bird turned resilient lioness", the song is built on a "winkly piano riff and beefy bass drums". "Dance for You" conveys a more sexual tone through breathy vocals and blaring electric guitars. It