A cappella group Anonymous 4 in concert December 3, 2009

Renowned for their unearthly vocal blend and virtuosic ensemble singing, a cappella quartet Anonymous 4 returns to San Francisco Performances with a holiday-themed concert. The program, entitled "The Cherry Tree," features medieval English carols and American Christmas songs.

The award-winning group - Ruth Cunningham, Susan Hellauer, Marsha Genensky and Jacqueline Horner-Kwiatek - create a magically ethereal sound through a combination of historical scholarship and contemporary performance intuition.

Founded in 1986, Anonymous 4 has performed on major concert series and at festivals throughout the world to support their 18 recordings of medieval, contemporary and American music. The group's CDs have sold nearly two million copies on the harmonia mundi label; the most recent is "Four Centuries of Chant," just released this fall.

The quartet's members bring a wealth of remarkable experience to their craft. As a sound healing practitioner, Ruth Cunningham works with individuals and groups on using the voice and music as tools for healing and transformation. California native Marsha Genensky has taught and done research at Stanford University and is the ensemble's American music historian. The group's medieval music research expert, Susan Hellauer, leads Chant Camp workshops throughout the United States. Irish-born Jacqueline Horner-Kwiatek is a longtime professional singer comfortable with a wide range of genres, from baroque to classical opera to new music.

Anonymous 4's 2004 release, "American Angels" (18th to 20th century folk psalmody, hymnody and gospel songs), spent 76 weeks on Billboard's Top Classical Chart. Their 2005 release, "The Origin of Fire" (sequel to their 1997 bestseller "11,000 Virgins, music of Hildegard of Bingen") was named in Amazon.com's Top 25 Classical CDs for 2005. For two consecutive years (2004 and 2005), the quartet was voted one of Billboard's Top Classical Artists of the Year.

Official Website: http://www.performances.org