Mr. Brown won numerous critics' and listeners' popularity polls, and was regularly included among the half-dozen or so greatest of all jazz bassists, along with Oscar Pettiford, Charles Mingus, Milt Hinton, and Jimmy Blanton, whose performances with Duke Ellington he counted among his greatest influences.
Mr. Brown, whose playing was featured on more than 2,000 recordings, played with Dizzy Gillespie, Charlie Parker and the others who invented bebop in the 1940's; was a long-standing member of the renowned Oscar Peterson Trio: and was part of the original lineup of the Modern Jazz Quartet. He accompanied singers from Frank Sinatra to Linda Ronstadt.
He also accompanied Ella Fitzgerald, to whom he was married from 1947 to 1952, and he continued as her musical director after their divorce.
Mr. Brown took the bass beyond its traditional ''thump-thump-thump'' to a much more sophisticated technique. But his playing remained rooted in a fundamental soufulness, which he called ''the grits and the gravy.''
Gillespie suggested that his sound was so deep and true you could hear the wood.
''Mr. Brown is still one of the best musicians out there,'' Ben Ratliff wrote in The New York Times in 2000. ''His notes are shapely -- fat and round and well-defined -- and his rhythm is so propelling that on up-tempo pieces his eighth-notes are always blowing wind into the music.''
The same year, Mike Joyce wrote in The Washington Post, ''One of the great and enduring joys of jazz is watching bassist Ray Brown dig his fingers into a deep, rhythmic groove until he's smiling like a kid who just got his hands on a new toy.''
Raymond Matthews Brown was born in Pittsburgh on Oct. 13, 1926. His father was an avid music listener, and Ray fell in love with the piano stylings of Duke Ellington, Count Basie, Fats Waller and Art Tatum. He began studying the piano at 8.
He decided to switch to the bass in high school when an opening became available in the school orchestra. He quickly became so good that he had to turn down offers to join traveling bands because he had promised his parents he would stay to finish high school.
After graduation he played with a couple of groups, and then, in 1945, decided to go to New York on his own. Within hours of arriving in Manhattan, he met Hank Jones, the pianist, who in turn introduced him to Gillespie. Gillespie hired him on the spot on the basis of only Mr. Jones's recommendation.
The next evening, Mr. Brown found himself onstage with Gillespie, Parker, Bud Powell and Max Roach, the giants of bebop, the new jazz style that was characterized by intricate harmonies and lightning fast speeds.
''Ray Brown, on bass, played the strongest, most fluid and imaginative bass lines in modern jazz at the time, with the exception of Oscar Pettiford,'' Gillespie wrote in his memoir, ''To Be or Not to Bop.''
After recording his classics ''One Bass Hit'' and ''Two Bass Hit'' with Gillespie's big band in 1946 and 1947, he formed his own trio with Mr. Jones and Charlie Smith on drums. Ms. Fitzgerald sang.
He, Ms. Fitzgerald and other star musicians participated in Norman Granz's Jazz at the Philharmonic tours during this period. In the early 1950's, Mr. Brown reunited with colleagues from the Gillespie band, Milt Jackson, John Lewis and Kenny Clarke, to form the original Modern Jazz Quartet.
From 1951 to 1966, he played in the Oscar Peterson Trio with Mr. Peterson and guitarist Herb Ellis. The group, known for Mr. Peterson's swirling, intricate solos, was consistently ranked as among jazz's most popular groups during the 1960's. Mr. Brown was almost always voted top bassist.
As an accompanist, Mr. Brown was ''the epitome of foresight, sympathetic foresight,'' Mr. Peterson said.
In 1966, Mr. Brown settled in Los Angeles, where he became a freelance and studio musician. In 1973, he recorded an album with Ellington, ''This One's for Blanton,'' a tribute to his hero.
His activities included playing on all of Sinatra's television specials, acting as director of the Monterey Jazz Festival for two years and as music director of the Concord Summer Festival in 1976 and 1977.
He is survived by his wife, Cecilia, and his son with Ms. Fitzgerald, Ray Brown Jr. of Hawaii.
In an interview this March with The Albuquerque Tribune, he was asked if he liked any of his albums more than others.
''The day you get satisfied and start liking what you play is the day you have to quit,'' he said. ''If you ask a musician what is their best album, they say, 'My next one.' ''