David Roback, the composer and guitarist for Mazzy Star, a soft-spoken, influential alternative rock group whose 1993 release “Fade Into You” became a hit despite the group’s stated indifference to commercial success, died on Monday at his home in Los Angeles. He was 61.

His mother, Rosemary Roback, said the cause was metastatic cancer.

The music of Mazzy Star, which Mr. Roback formed with the singer Hope Sandoval in the late 1980s, combined his hazy, reverberating guitar playing with Ms. Sandoval’s haunting, enigmatic vocals. Contemporary pop artists like Lana Del Rey and the xx have since embraced a similarly intimate aesthetic.

Mazzy Star released its first album, “She Hangs Brightly,” in 1990. Mr. Roback and Ms. Sandoval played with a shifting lineup of other musicians, including the drummer Keith Mitchell and the bassist Jill Emery.

According to Mr. Roback, mainstream success was not the point.

“It doesn’t matter how well our records do,” he told The San Diego Union-Tribune in 1990. “None of that matters, because we’re completely free.”