Brown died in his sleep Tuesday in Indianapolis where he was concluding the U.S. leg of a tour, said John Clayton, a friend and fellow bassist.

Brown, whose fluid sound defined the “Be-Bop” era, started his career in the 1940s and performed during jazz’s Golden Age with Gillespie, Parker and Bud Powell.

He was a founder of “Be-Bop” and appeared with Gillespie in the 1946 film “Jivin’ in Be-Bop.” Brown later became musical director and husband of singer Ella Fitzgerald, whom he later divorced.

“Ray played with such strength and power and he had such great musical knowledge, he knew every right note to play and he had the most fantastic technique,” said drummer Frank Capp, a close friend.

Ray Matthews Brown was born in Pittsburgh in 1926 and moved to New York in 1945 where he was immediately involved in the emerging Be-Bop revolution. While playing in Gillespie’s Big Band in 1946 and 1947, he became Fitzgerald’s music director, as well as her husband in the late 1940’s, and worked with her even after their divorce.

Brown played with an early edition of what became the Modern Jazz Quartet, recording with the Milt Jackson Quartet in 1951. He subsequently joined Oscar Peterson’s Trio, which ranked among jazz’s most popular groups of the 50’s and 60’s. He also was voted top bassist consistently in critics’ polls during the decade.

Brown proved the ideal partner for Peterson’s swirling, intricate solos.

The Peterson-Brown-Herb Ellis lineup stayed intact until 1957 and Brown remained with Peterson until 1966.

He started playing cello and became as skilled on it as he was on the bass.

In 1960, Brown created a stir when he had a hybrid instrument built for him that combined features of the cello and bass. The experiment attracted plenty of interest and eventually Ron Carter had a piccolo designed along similar lines.

After leaving the Oscar Peterson Trio in the mid-1960s, Brown moved to California. He co-founded the group L.A. Four and appeared on the “Merv Griffin Show.”

Among his recordings is the solo effort Something for Lester.

“He is the primary contributor to Be-Bop from a bassist’s standpoint,” Clayton said. “We had Dizzie Gillespie, Charlie Parker and Thelonious Monk and there to contribute from the bass chair is Ray Brown. He was extremely important in jazz education, leading a lot of young bass players to learn the instrument.”

Brown lived in the Sherman Oaks area of Los Angeles with his wife, Cecilia.

Brown was finishing an engagement at the Jazz Kitchen in Indianapolis at the time of his death.

Brown had played golf earlier Tuesday and went to take an afternoon nap, Clayton said. When he did not show up to perform, a bandmate went to his hotel where his body was found in his room.

Along with his wife, he is survived by a son, Ray Brown Jr., of Hawaii.