There's no better man than Eddie Vedder to inspire a rocker movie character

There’s no better man than Eddie Vedder to inspire a rocker movie character.

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“I went up to Seattle and spent four or five days with him and I asked him 9,000 questions,” Cooper, 43, told Yahoo Entertainment. “And he gave me minor, little things that only musicians know about what to do, just aesthetically and the inner workings.”

Image zoom Bradley Cooper and Lady Gaga Neal Preston/Warner Bros.

Even though Vedder, 53, was initially skeptical about his friend’s decision to sing on-screen — “He was like, ‘What? Bro, don’t do that,’ ” Cooper recalled — he eventually passed on his musical genius by giving notes for the songs in the film.

“He was wonderful,” Cooper, who also directed A Star Is Born, said.

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The Hangover actor’s relationship with Vedder isn’t the only one that’s blossomed as a result of the film. Cooper told PEOPLE on Monday night that he’s “made a friend for life” in his costar Lady Gaga.

“As great as this movie was, the thing that I think I’ll take away forever is the relationship I have with her because she is an incredible person. I’m very lucky to have worked with her,” the father of one said.

When it came to meeting her for the film, Cooper visited the pop star at her home, and they bonded over a meal.

Image zoom Bradley Cooper and Lady Gaga

“That was absolutely insane. When you’re telling it, I can’t believe that happened,” Cooper recalled, adding he felt nervous singing for her. “The only reason I had the courage is because she made me feel so comfortable.”

Cooper said he used a video of their first duet for a pitch meeting, adding it “just sort of happened.”

“I didn’t know we were going to record it. She stopped after the first verse and said has anyone heard you sing? I said not really. She said, ‘Well, let’s record.’ The chemistry felt so good and so easy that I went to Warner Bros. the next day and played it for them,” he explained.

As for Cooper’s interest in pursuing a musical career, the actor said, “The answer, shooting from the hip answer is no, it’s not me, it’s the character.”

Image zoom Bradley Cooper and Lady Gaga Dominique Charriau/WireImage

“I don’t even know how I would sing because I’m singing through him. He was a complete character. That said, there was one song that I wrote, called ‘Too Far Gone’ that I had the idea for a verse and a bridge, so I’m going to go to the recording studio and finish it,” he said. “So I don’t know what the answer is.”