When Def Leppard fans might have gotten worried when they heard that country star Tim McGraw had been brought in as guest singer on a track from the band’s 10th album, Songs From the Sparkle Lounge.

It wasn’t the first time. Fans had long wanted them to keep doing 1987’s Hysteria, and they also didn’t want the band to stop changing. In fact, Def Leppard had been victim to that particular nuance of world domination ever since they set out to become the biggest band in the world. ("And for a short time," singer Joe Elliott famously said, "we were.")

Fortunately, the group from Sheffield, England, had the kind of forthright attitude that comes out of working-class city places like that. When they began to focus on the follow-up to 2006 covers album Yeah!, they made a list of requirements for themselves.

“There was a thought process behind it that we wanted to deliver a specific kind of record, but that specific kind of record was, if you like, a non-specific kind of record,” Elliott told Billboard in 2008. “We weren't going to try to theme it to the point of Pyromania, where it's got a drum sound that was definitive in 1983 ... [or] Hysteria, when we had a definite, like, overall '80s sound. With this one it was a case of, ‘Let's just hone in on the songwriting and we'll use 2008 production techniques, if you like, to make it sound more like a '70s record.’ It sounds very complicated, but it actually wasn’t.”

The plan at one stage was to reunite with classic-era producer Mutt Lange, but schedules made that impossible. Instead, Def Leppard sought inspiration from early AC/DC and Led Zeppelin, while not fully abandoning the complex layered approach that had made their name.

“We took a lot of songs that were already half-written and it was a lot easier,” Elliott said, noting that they were usually “terrible” at trying to write from scratch on the road. “We'd go in and really work on these songs, and by the time we started recording them we knew them really well and there was not that much of a learning process. ... So, it was probably the best recording situation for new music we've ever had.”

The Sparkle Lounge, incidentally, was the name their crew gave to their tuning trailer on tour, fitted out with cut-down versions of each member’s stage rig. “The crew started having a bit of fun with it, putting in sparkly lights, candles, incense – you name it,” Elliott told Billboard. “It turned into this very atmospheric little workspace.”

Despite that, guitarist Phil Collen regretted that they weren't more collaborative with their writing. Asked how they pushed each other “musically and creatively,” Collen told Inside Out: “We didn't, really. It was like doing four separate projects, and everybody came in with different songs. … Joe came in with something, even Vivian [Campbell] and [Rick] Savage, and we literally did three songs from each person – well, four in my case. It really saved a lot of pressure and was a lot easier process.

“Vivian and I play very well together,” Collen continued. “The timing is just bang-on, and if you put a pair of headphones on and listen to us live we are really in sync. The only thing that we wanted to do for a while is work on some of the songs together. We have been trying to push for that for a few years now … it just hasn't happened; we normally work on pieces separately. With this record, me and Vivian done a lot of the rhythm guitar parts together in the same room and it really helps, it gives it that identity, if you like. I think it's something to look forward to for the future.”

Watch the Video for Def Leppard's 'Nine Lives'

Def Leppard studiously refused to perform any of the 11 new tracks live before the Songs From the Sparkle Lounge’s release. They didn’t want the impact of new material diminished by leaks on MySpace, which was still bigger than Facebook – while YouTube wasn’t yet regarded as a social-media channel. So, when the news that McGraw had sang on a song began circulating, it triggered alarm bells in some quarters.

The situation wasn’t clarified until “Nine Lives,” the track on which he appeared, arrived a few days before the album’s release on April 25, 2008.

“I know some people might think that someone shoved Tim McGraw in our face, but it wasn't like that at all,” Elliott insisted, arguing that the band practiced what he called a “Roger Waters syndrome” in that no one could tell Waters how to make a Pink Floyd album, and no one could tell Def Leppard how to make one of theirs.

“People have been bringing that question up: ‘You guys have gone country?’ ‘No! Tim went rock!'" Elliott told Billboard. "And truth be known, that's really what he did. If you listen to the record, he goes off on his own kind of twangy tangent for the beginning part, but after that, even me and him could barely distinguish one from another. ... So, he really stepped up to the plate in the rock sense.”

When it came to the album cover, Def Leppard settled on a theme inspired by the Beatles’ classic Sgt. Pepper’s Lonely Hearts Club Band before they involved designer Richard Proctor. A handful of alternatives were briefly considered, but that’s the concept they went with.

“There was no hard and fast rule about who was in or out. We just wanted the audience to look as diverse as possible,” Proctor told DefLeppard.com. “Every character has some sort of Def Leppard or theater reference. We also wanted to create the feeling of that when every time you looked at the sleeve artwork you saw a new character. I can only think of one character that didn't make it on to the sleeve ... but I won't go into details!”

Songs From the Sparkle Lounge> debuted at No. 5 in the U.S., No. 7 in Canada and No. 10 in the U.K., but faring less well in other markets. The release was bolstered with a second single, “C’mon C’mon,” and the band undertook what became the 49th-biggest-grossing tour of 2009. No mean feat for a group that had already been around for more than 30 years.

If Def Leppard had ever come close to pleasing all of the people all of the time, it had doubtlessly been during their Hysteria era. The new material drew praise for the writing quality, but there was still some negativity over the production. Rolling Stone said the tracks resembled “inferior versions of hits two decades past,” adding: “It's clear they're missing their old producer.”

Perhaps, had Mutt Lange been available, they could have once again pleased all of the people all of the time.

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