Though Duncan Sheik [ tickets ] is no stranger to the pop charts--"Barely Breathing" from his self-titled 1998 debut spent 55 weeks on the Billboard Hot 100--the singer-songwriter said he has become disenchanted with "the commercial aspects of production and songwriting."

It was a subtle suggestion from his friend, New York playwright Steven Sater, that led to the idea that would free him from conventional pop. Sater, whom Sheik met at the Buddhist organization Soka Gakkai International, asked Sheik to write a song based on a lyric that a character pens in Sater’s play "Umbrage." The result was "Phantom Moon" (Nonesuch Records), which hit stores in February.

"Steven and I are both practicing Buddhists," Sheik said. "We just got together to chant and hang out and then he mentioned that he had this play. He asked if I wanted to set that lyric to music, which I did. Then Steven just started faxing me all these lyrics. Some of them had to do with ‘Umbrage.’ I was really inspired by what he wanted me to do. I wanted to make a particular kind of record, and his kind of lyricism seemed to be the kind of lyricism for that."

Ultimately, Sheik added, the score and the soundtrack will accompany the independent film version of "Umbrage."

Sheik explained that the writing material for his own records and for plays and films are two completely different processes.

"In some ways, [writing ‘Phantom Moon’] was much easier. The words were there in front of me. I just had to figure out the music."

The mostly acoustic "Phantom Moon" is a departure for Sheik. In the opening number, "The Wilderness (Prelude)," Sheik’s quiet vocals are backed by a piano, while strings weigh heavily in "Mouth on Fire." "This Is How My Heart Heard" blends Sater’s romanticism with Sheik’s atmospheric vocals.

The project was the first of two collaborations between the duo. They later developed music for "Spring Awakening," which was written by German playwright Frank Wedekind in 1891. The "anti-musical," as Sheik calls it, will debut in New York in fall 2002.

"It’s very different than musicals, [more] like music that you would hear on my record."

Sheik is preparing to head out on tour in support of "Phantom Moon." The run, which begins on April 9 in Minneapolis, is a mixed bag of acoustic and "plugged-in" dates, depending on the city.

"The bigger shows in bigger cities will be with the band. It will mostly be a mix of the three records and maybe some surprises. It kind of depends on [what time allows]."

If this tour goes well, Sheik is hoping to head out again with a string section and a band. "It just depends on people’s desire to see that," he said.

Sheik recently began work on his fourth album. He said that his new material will go beyond pop's traditional framework.

"Basically, [I will be] using pop conventions, [yet] trying to make music interesting despite the fact that there’s this really tight formula," Sheik explained.

"I’m not going to name names, but there are certain songs on the radio that are total pop songs ... really smart, interesting, clever or artfully done. The art side is not obvious. That’s what I’m attempting to do on this next record."

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