The addition of other members to +44 came gradually. In April 2005, Barker invited his friend Carol Heller to provide vocals on a track. Formerly of the all-girl punk quartet Get the Girl, Heller shared vocals with Hoppus on most of the band's early demos. Meanwhile, Hoppus invited friend Shane Gallagher to play guitar on a few tracks the band began working on, and he soon joined the group. Production on the record moved along swiftly once the duo purchased their own North Hollywood studio, which they dubbed Opra Music. The space — which featured two recording rooms, a lounge and a small outdoor courtyard — was purchased in October 2005 from former Poison guitarist Richie Kotzen. After moving all band gear into the new recording center, the entire direction for the band changed course significantly, opting for a more rock-based sound. Hoppus and Barker had believed the electronic elements would always be a startup method and nothing more; Hoppus told label executives near the beginning of the project that "We’re just using these tools at the beginning to start off this thing." Heller became uneasy with the new direction and, with a desire to start a family, parted ways with the band by the end of the year. Shortly afterward, friend Craig Fairbaugh came in to observe and listen and play to songs; he was later asked to become the fourth member of the group.