The Del Sol Quartet specializes in contemporary music and has commissioned hundreds of works from a diverse group of composers in the U.S. and beyond. The group sometimes performs music calling for just intonation.

The Del Sol Quartet, which often uses the truncated name Del Sol, was founded in San Francisco in 1992. Its members include violinists Benjamin Kreith and Samuel Weiser, violist Charlton Lee, and cellist Kathryn Bates; several of the members have been present since the group was first established. Lee was inspired to assemble the quartet as he drove by the Fermilab facility in Ilinois and began to muse on the relationship between artistic and scientific creativity; the group describes itself as "[f]ascinated by the feedback loop between social change, technology, and artistic innovation." Del Sol found prestigious residencies early on at the Banff Centre for the Arts in Canada and San Francisco State University. The group released its debut album, Tear, on its own label in 2002; the album contained works by composers as diverse as Astor Piazzolla, Ruth Crawford Seeger, and John Harbison, and a wide range of contemporary music, with an international orientation, has characterized the quartet's music-making ever since. The group was aided by various honors, including an ASCAP award for Adventurous Programming of Contemporary Music.

The Del Sol Quartet has performed at numerous notable venues, including the Library of Congress, the Hobby Center for the Performing Arts in Houston, and the Chengdu Festival of Contemporary Music in China. The group has commissioned new works from a wide range of composers in the U.S. and other countries, including Frederic Rzewski, Chinary Ung, and Terry Riley, whose Dark Queen Mantra the quartet premiered in 2017 with guitarist Gyan Riley. Del Sol's interest in music calling for just intonation tuning (instruments tuned to pure intervals) represents an unusual specialty; the group has performed works in this vein by Ben Johnston (Del Sol is the only quartet touring with Johnston's notoriously difficult quartets, which the group has played at the Library of Congress), Theresa Wong, and Michael Harrison, among others. Del Sol established the Pacific Pythagorean Music Festival in 2019 to explore music of this type. The Del Sol Quartet has released nine albums on the Other Minds, Dorian Sono Luminus, and New World Records labels. Educational outreach in the San Francisco Bay Area forms a major aspect of the group's activities; it has appeared in this capacity at the San Francisco Symphony Adventures in Music series, San Francisco Libraries, and Music at Kohl Mansion, among other venues, and it has worked closely with student and faculty composers at various universities. In 2021, the quartet was heard on the Bright Shiny Things label on the album Huang Ro's A Dust in Time. ~ James Manheim, Rovi