When it came to making the soundtrack for “A Star Is Born,” Lady Gaga says one of her most important jobs was keeping people away from Bradley Cooper.

During her Variety Actors on Actors interview with Lin-Manuel Miranda, Gaga says she was forced to act as a “gatekeeper” in order to keep people from trying to influence the actor’s musical voice. Gaga wanted Cooper to discover his own sound, and she says the resulting deep baritone became the nucleus for the rest of the film’s music.

When asked about her songwriting, however, Gaga says the process was actually quite collaborative. Gaga wanted a whole “force” of writers behind her, she says, so that she could incorporate as many opinions as possible. She also had to account for the influences on her character, Ally’s, music after she joined forces with Cooper’s character Jackson.

To compensate, Gaga says she filtered everything through Lukas Nelson, the real-life head of Jackson’s fictional band, so that Ally’s music would evolve alongside her relationship with Jackson. Whether it was lyrics, songs, or demos, Gaga says everything went though Nelson’s band.

“Often in, I have found, alcoholic relationships, there’s sort of a taking on of the identity of the one that you’re with,” Gaga says. “It’s a way to bond; it’s a trauma bond, so I knew that she would want to kind of become a part of him, so that’s how that started.”