Mark Kozelek's unique interpretive bent (AC/DC, John Denver, Modest Mouse) has been an integral part of his work with Red House Painters, Sun Kil Moon and as a solo artist.

Mark Kozelek's unique interpretive bent (AC/DC, John Denver, Modest Mouse) has been an integral part of his work with Red House Painters, Sun Kil Moon and as a solo artist. But his original compositions have always packed more of an emotional punch, and their impact is stronger than ever on Sun Kil Moon's "April," the proper follow-up to 2003's "Ghosts of the Great Highway," the second-best-selling album of Kozelek's career.

The trademark sprawling rockers ("Tonight in Bilbao," "The Light") are present on "April," due this week via Kozelek's own Caldo Verde label, as are devastating snapshots of crumbled relationships ("Moorestown," the solo acoustic "Blue Orchids"). Elsewhere, cult favorite indie singer/songwriter Will Oldham guests on "Unlit Hallway" and "Like the River."

"I heard his voice in there, so I mailed him the songs," Kozelek says of Oldham, who he met in the late '90s during an in-store at San Francisco's Amoeba Records. "In very Will Oldham style, he turned them around almost overnight. He added so much color. I think my favorite part of the whole album is his back-ups on 'Unlit Hallway.'"

"Many of the songs on this record do deal with a certain relationship, which does give it a certain theme," Kozelek adds, "but I wasn't thinking about it, or constructing it that way. I don't really think about stuff like that when putting a record together, which is probably why many of my records are scattered musically, and subject-wise."