Born into a musical family (his father was a composer and his mother taught piano), Charles Rex started his violin studies at age four. Following his debut with the Florida Symphony at age thirteen, Mr. Rex won the Hinda Honigmann Scholarship Award to the Brevard Music Center in North Carolina and toured as soloist with its orchestra throughout the Carolinas. He was awarded a full scholarship to Florida State University, where he studied with Richard Burgin, former Concertmaster and Associate Conductor of the Boston Symphony. During this time, he won the string division of the MTNA National Young Artists Competition and soloed with the Cincinnati Symphony under Max Rudolf. Immediately after graduating cum laude from FSU, Mr. Rex joined the Philadelphia Orchestra under Eugene Ormandy where he played for eight years before accepting the position of Associate Concertmaster of the New York Philharmonic under Zubin Mehta. He relinquished the position in 1999 due to an increasing demand of his time for solo appearances and recordings. Mr. Rex has also served as guest concertmaster of the London Symphony under Sir Colin Davis and also acted as concertmaster of the Dallas, Reading and Delaware Symphonies.

In 1982, Florida State University honored him as a Distinguished Alumnus, and the FSU School of Music presented him with the Ernst von Dohnanyi Faculty Citation for Excellence in Performance. In 1988, he toured Egypt and Jordan as soloist with the Princeton Chamber Orchestra and was the first American to appear as soloist in the new Cairo Opera House. The Borough of Staten Island of New York City also made March 13 of that year "Charles Rex Day" on the occasion of a special recital he performed there on behalf of the New York Philharmonic. At Lincoln Center, Mr. Rex has been soloist with the New York Philharmonic in performances of Vivaldi's "Four Seasons," the Hindemith Concerto and the Nielsen Concerto to great critical acclaim, and he also gave the New York premiere of the Harbison Violin Concerto. He performed the Bach Double Concerto on a Philharmonic tour of Japan, India, Korea, Hong Kong and Taiwan. In October of 1992, he gave the world premiere of a new violin concerto written by the American composer, David Ott, for the Reading Symphony's 80th Anniversary. During the New York Philharmonic's 1993-1994 season, Mr. Rex and his brother, Christopher (the Principal Cellist of the Atlanta Symphony), premiered a new Double Concerto by Stephen Paulus, a New York Philharmonic 150th Anniversary Commission in conjunction with the Atlanta Symphony.