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Where were you when the joint Beyoncé and Jay-Z album dropped?

Producer duo Cool and Dre won’t forget the answer to the question on everybody’s minds this weekend anytime soon. After all, they were right alongside the Carters on tour in London, having literally put finishing touches on Everything Is Love just a few hours before it arrived with no warning on Saturday evening.

But just because the album’s release came down to the wire doesn’t mean its creation was hasty: Marcello “Cool” Valenzo and Andre “Dre” Lyon describe the work ethic of hip-hop’s perfectionist power couple as nothing short of fastidious — no drum sound, sample or melody was spared their scrutiny. Below, Cool and Dre take Billboard behind the scenes of their Paris stadium sessions, Beyoncé’s hands-on role in the writing process and just how much music they have left in the vault.

Beyoncé and Jay-Z work in mysterious ways. Were you surprised that the album came out when it did?

Dre: Nah, we knew what was going on. We were in London with them when the album dropped. Jay-Z and Beyonce are Golden State Warriors: They shoot half-court shots, and it goes in. We spent three weeks in Paris recording, then we went to Cardiff for like a week. We got to London and knocked out two to three tracks [within] 10 days of finishing up the album. An hour and a half before showtime, Bey and Jay were still cutting up vocals. Three hours later, it was released to the world. There are no rules when it comes to those two.

Were you racing to meet a deadline, or was that just when they decided to release it?

Cool: We knew that they were in the last stages of the project. The whole release and all that, that was their genius. Me and Dre were just happy to be there. We thought maybe this shit was going to come out a few weeks down the line, but they finished up and felt good enough about the material they had to let the world hear it.

When did you get involved in the project?

Dre: I would say seven or eight weeks ago. I was sending Jay new records that Cool and I were working on, nothing in particular or for anything. Jay had mentioned a long time ago, “Whenever you feel you got that heat, that undeniable shit, play it for me before you play it for anyone else.” I was emailing with him back and forth. He was feeling it and asked me to come out to the palace in L.A. We cut a good five or six records — not full songs, just ideas here and there. Then he played me two or three joint records [he recorded with Beyonce]. I was like, “Man, I have one more,” and the last record I played was “SALUD!” Bey walked in during the middle of me recording the hook and loved it and listened to it about four or five times. When I got back to Miami a week later, he hit me, like, “Bey cut ‘SALUD!’ Congrats!” Then his engineer, Young Guru, hit me, like, “We’re going to Paris — if you want to come out, let’s keep going!” Two days in Paris turned out to be three weeks. It was a life-changing experience. It’s been unbelievable, and we’re so thankful to even be a part of this shit.

It’s interesting that this album came together so quickly — a joint album between Jay-Z and Beyonce has been rumored for so long, and Jay-Z even said in an interview that they were working on one before Lemonade came out.

Dre: I don’t know why they released it when they did or what their thinking was. I was just focused on not stopping. Jay and Bey kept telling me and Cool, “Don’t stop, just keep giving us that heat.” We’re dealing with people that move when they feel it’s right. You could be doing something for three years and maybe not feel like it’s time. And if that means you have to record 14 records in four weeks, that’s what has to happen. You’re dealing with two genius-level talents.

Are you in the same room with them at the same time, or do they record separately?

Dre: We were blessed. They booked the owners’ suites of the stadium they were rehearsing the tour at in Paris. They rented a stadium to prepare for the tour and bought out all the owners’ suites and converted them into studios. Our owners’ box was right above the tunnels they would walk underneath after they rehearsed. Cool and I would purposely open up our doors upstairs and blast music while they were walking through, and they would look up and pop up into our room every other day. It was like a club in the Cool and Dre studio. There were times when they were together and we’d play them what we were working on. There were two or three times when they’d call us in to make a change. And other times it was just Jay in his room doing what he does, and we’re in the room with him.

Were other producers on the album, like Pharrell and Boi-1da, working in other suites simultaneously?

Dre: I didn’t see Pharrell, but Boi-1da, he was definitely in Paris for a couple days. That’s our guy. He did two amazing records on the album. We were definitely catching a vibe. There were some songwriters there as well. It wasn’t a lot of people.

Did they give you any instructions about what kind of vibe they were going for? Or did they just want your best material?

Dre: In our case, we just kept seeing them [and playing them music]. When we played them “SUMMER,” we would tell Bey and Jay, “If you don’t like the melody or the words, we’ll change them. We want to do anything to be a part of this.” They were like, “No, we love it, don’t stop.” That was the greatest thing they would tell me and Cool: not to stop.

They were really feeling what we were presenting to them. Of course, once they did a record, [they had feedback]. On “BLACK EFFECT,” the drums were more of a steady hip-hop beat, and Jay was like, “I want this to bounce more — change the drum track and make it bounce!” And on records like “SUMMER,” Beyoncé would be like, “I want to hear strings; I want to hear horns. Use my string section, use my horns — I got them all here.” They really produced these records with us. That’s why it says produced by Beyonce and Jay-Z and Cool and Dre. They definitely gave us direction. And when we were doing it right, they told us not to stop.

How involved was Beyonce in the writing process?

Dre: She was 100 percent involved. She put her mind to the music and did her thing. If she had a melody idea, she came up with the words. If we had the words, she came up with the melody. She’s a beast.

I’ll tell you one story: When I went out to their compound, I played them a sample that had a lady singing in French [on] a loop throughout the whole record. Bey said to play it again, and I did. And then she said to play it again, and I did. On the third time, she sang the whole sample from beginning to end — in a different language! When you make a beat, that could take hours, days. I didn’t know what the hell that sample was saying. But in three listens, she picked up on a sample in a different language and sang the whole thing. When I saw that, I was like, “This is a totally different level.”