When Enya entered the top 40 with "Orinoco Flow" in the spring of 1989, she brought a breath of fresh air to pop radio — but no matter how solidly her sound resonated, it remained so far outside the mainstream that she seemed destined for one-hit wonder status. Until, that is, she returned with her next LP.

Released Nov. 4, 1991, Enya's third solo effort, Shepherd Moons, proved she had everything it took to maintain multi-platinum status and then some. Just as she'd done with the previous release, she did it all her way — and ended up reaching more listeners than ever before.

Perhaps because Enya's New Age-infused, Celtic-tinged pop sound was so distinctive, she didn't face the usual questions when following up her first major hit. Instead of worrying over how to expand, advance, or reinvent her music, she simply set about making more of it; starting in 1989, she set up shop in the studio with her longtime collaborators, producer Nicky Ryan and his wife, Roma Ryan. As Enya later told Jazziz, once she got back to work, the act of making new music allowed her to ignore all the distractions that went with worldwide stardom.

"It's strange because once you open that door, it's like when I went into work on Shepherd Moons, it felt like Watermark was a dream. It felt like it hadn't happened," she recalled. "And in a way it's nice because you can concentrate only on the music. You can forget about charts, how much you sold. You forget that."

One way Enya's increased sales definitely did help was in terms of her recording budget, which increased to go along with her raised profile — a significant development for an artist whose heavily layered sound benefited from up-to-the-minute technology and more time in the studio. She and the Ryans were afforded both during the recording of Shepherd Moons, which unfolded between Dublin and London over a two-year period while Enya painstakingly assembled each of the album's 12 songs, playing many of the instruments herself and overdubbing dozens of vocal lines.

In an interview with the Irish Times after Shepherd Moons' release, Enya pointed to two of the album's tracks as examples of how slow her creative process could be in the studio — and how audibly the ends often justified the means. "So many times we work on a track, like 'Caribbean Blue,' and when we find it's not working we strip it right back to basics and reconstruct everything again, even the lyrics," she pointed out. "And sometimes this process involves undoing a tremendous amount of work. For example 'Angeles' on the album has approximately 500 vocals on it. And it's as difficult and demanding, each time, to sing multi-vocals as it is to do a lead vocal."

Once that arduous process was completed, Enya handed off the arrangements to Roma Ryan for lyrics — a partnership understandably fraught with potential for creative tension, but one that seemed to unfold seamlessly from a shared musical canvas populated with ideas that had been refined and cultivated through a great deal of effort.

"Melody is really important. I'm looking for something that is saying something very strongly to me, emotionally. I feel if this happens, then it's strong enough to work on. But this takes time," Enya told the Boston Globe. "I record a lot of ideas and listen back and eventually I know that a melody will evolve from all this work. But sometimes it's so difficult to know. And what's it going to be like?"

After focusing so strongly on the work for the better part of two years, Enya admitted to a certain amount of stage fright — as she told the Boston Globe, upon finishing Shepherd Moons, she asked herself "What have I done?" — and even after starting the press tour for the record, she told Q she was so worked up over whether or not the record was any good that she'd avoided listening to most of it.

"I've not actually sat down and listened to the album through, since the last night of mixing it. I will find any excuse not to," she insisted. "And honestly, I have never felt so miserable as finishing this album. It's fear - fear that all your feelings and all your emotions have gone into the thing, and when you hear it, it won't live up to your expectations for it."

Enya's expectations notwithstanding, Shepherd Moons proved an immediate and tremendous success. Although it failed to generate a hit single on the same level as "Orinoco Flow," the album exceeded its predecessor's sales totals, going on to sell an impressive five million copies in the U.S. alone — and 13 million worldwide — on its way to winning an array of awards that included a Grammy for Best New Age Album. Three years removed from notching a hit that sounded like a once-in-a-generation aberration, Enya was well on her way to establishing herself as a one-artist genre.

That, in essence, is exactly what she's done over the ensuing years. Since Shepherd Moons's release, there have been six full-length albums credited to Enya, and none of them have sold less than a million copies worldwide — a remarkable streak of commercial success when you consider not only the downward trend in music sales since the turn of the millennium, but also Enya's tendency to take extended breaks between releases. By staying true to herself and positioning herself resolutely outside the mainstream, she made herself a musical beacon for listeners searching for a soothing oasis — one to which they continue to return.

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