Randel, Don Michel edit. Harvard Biographical Dictionary of Music.
Belknap Press 1996. 0674372999 / 9780674372993 Hardcover in DJ. Good Good
This book contains compact biographies of 5500 composers, performers, instrument makers, and music theorists, from Pietro Aaron to Ellen Taaffe Zwilich. Though many of these entries concern figures from the world of classical or art music, 20th century jazz, rock, and pop musicians are also represented, as well as hymn and show tune writers.