Def Leppard committed to a return to their classic sound after a mid-'90s swerve into grunge – and they said the more pop-leaning X was an extension of that. After all, singer Joe Elliott argued, 1987's Hysteria was powered to diamond-selling status by no fewer than six hit singles.

"We said this time round, 'You know what, let's just make great songs' – and if they are all pop songs, they are still going to be guitar-based pop songs," he told Paul Flanaghan in 2002. "Pop is a strange word; pop's become this word that you think of as pap. 'Pop' is short for popular, and that can be anything from Black Sabbath to Charlotte Church."

To get there, Def Leppard turned to proven hands. X arrived on July 30, 2002, with a series of radio-ready collaborations, including the Top 25 U.K. hit "Now," written with veteran hitmaker Marti Frederiksen; and "Unbelievable," which was co-composed and produced by the Swedish team of Andreas Carlsson and Per Aldeheim. (The latter had already scored with the Backstreet Boys, *NSYNC and Britney Spears.) "Long, Long Way to Go," a U.K. Top 40 hit, was co-written by Wayne Hector, who has worked with Nicki Minaj and One Direction.

It was, to put a fine point on it, the exact opposite from the edgy focus of 1996's Slang. "Well, music was dark and miserable then," guitarist Phil Collen told Yahoo in 2002. "We thought Slang was a great album, but people said, 'Oh no, we wanna hear Def Leppard.'"

So, their first, perhaps not unexpected move was to reunite with platinum-era producer Mutt Lange for 1999's Euphoria. He ended up working on three songs as Def Leppard scored a gold-selling, willfully retrograde album that just missed the Top 10. The band then gathered in Elliott's house in Dublin to sketch out their next step, and found inspiration in Aerosmith's latest update to their tried-and-true sound on 2002's Just Push Play.

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"We heard 'Jaded,' the song Aerosmith wrote with Marti Frederiksen," Collen told VH-1 in 2002, "and thought, 'Wow, this sounds cool. It sounds contemporary and energetic. But it's obviously Aerosmith. Wouldn't it be great if there was a Def Leppard version of that?' We got Marti Frederiksen and it was instant. He's a multi-talented musician with the enthusiasm of an eight-year-old boy. It influenced the rest of the album."

In the end, however, there were limits – even for a band committed to making something aimed at mainstream pop listeners. For instance, Def Leppard ended up adding in a few songs exploring the down side of relationships. "It was getting too lovey-dovey, so we had to write some hate in there, as well," Elliott told VH-1. "It's love and hate and jealousy and envy. Anything that people can go, 'Yep. I've been there and done that myself, or seen that in somebody else's life.'"

X ultimately finished at No. 11 on the Billboard charts, the same spot as Euphoria. But Def Leppard walked away from this experimental era without regrets. "If we hadn't have done [Slang], we wouldn't have gotten to this point," Collen told Yahoo in 2002. "Plus, I think there's some great stuff on that. I think it's got some earnest stuff – some basic, really brave songwriting. It was brave because we didn't do the 'Def Leppard thing.'"

Elliott took a long-range view on X, too. Decades into their career, he felt Def Leppard fans understood the desire to explore new musical avenues. Besides, he insisted that X was getting a bad rap as their "pop" album.

"If you listen to the album to songs like 'Cry,' 'You're So Beautiful,' 'Scar,' there's rock in it," Elliott said in a USA Today Q&A in 2002. "But our audience is prepared to let us be. When we did Slang, it was a total commercial failure, but it was an artistic success.
Euphoria was a paint-by-numbers record. So no, we're not afraid. I don't expect Slipknot fans to buy this, but those who listen to Slipknot and Alanis Morrisette will."

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