Dave Brubeck changed the sound of jazz in profound ways, unexpectedly becoming something of a pop star in the process.

Starting in the mid-1950s, in fact, he emerged as a symbol of jazz in America, and well beyond, gracing the cover of Time magazine in 1954 and selling more than a million copies of "Take Five" in 1960. To this day, the puckishly syncopated tune remains one of the most recognizable in jazz, though Brubeck didn't write it – his alto saxophonist, Paul Desmond, did.

Beneath the popular acclaim stood a brilliant, uncompromising composer-pianist who challenged conventional jazz techniques, brought the music to American college campuses and helped break down racial barriers through a music uniquely suited to that task.

Brubeck was en route to an appointment with his cardiologist when he was stricken Wednesday morning, said his longtime manager-producer-conductor, Russell Gloyd. The pianist died of heart failure at Norwalk Hospital, in Norwalk, Conn., near his home in Wilton, Conn.

Brubeck was anticipating a birthday concert Thursday, when he would have turned 92. The performance will go on, but in the form of a tribute, in Waterbury, Conn.

"Dave Brubeck was one of the giants in the music – he changed the way people listened to the music," said David Baker, distinguished professor of music at Indiana University and a friend of the Brubeck family.

"He could swing in any time signature – it seemed like forward motion was born in his blood," said pianist Ramsey Lewis, who played four-hand piano with Brubeck at the Ravinia Festival in Highland Park in 2010. Though the Ravinia Festival does not release attendance figures, a huge audience turned out for that concert, a celebration of Lewis' 75th birthday.

"Playing with Dave at Ravinia was one of the most exciting moments in my life," added Lewis.

Brubeck's last performance in the Chicago area was a 2011 Father's Day show at Ravinia, where the 90-year-old pianist shared the stage with four sons: pianist Darius, trombonist Chris, cellist Matt and drummer Dan. The elder Brubeck also consistently drew large audiences to Symphony Center, where he last played in 2009.

"Dave Brubeck was one of few jazz headliners who was guaranteed to bring in a large crowd," said Nick Pullia, Ravinia Festival communications director.

Though widely beloved as an elder statesman in jazz during recent decades, Brubeck's initial burst of immense popularity, more than half a century ago, caused a backlash. When "Take Five" made him a household name, some critics and deejays accused him of selling out, he said in a 1990 Tribune interview.

"But I had a lot of fun with them," recalled Brubeck. "One of the most internationally known disc jockeys accused me, right on the air, of going commercial.

"So I said to him, on the air: 'OK, let's play the ('Take Five') record, and you follow along and count it,'" said Brubeck, referring to its underlying rhythmic pattern, which defied the two-, three- and four-beats-to-the-bar techniques of the day.

"And there was this huge blank – he didn't say anything.

"So I said, 'Well, why don't you do it?'

"And he just didn't answer.

"At that time, hardly any musicians could play 'Take Five.' Now a grammar school kid can play it.

"But those were breakthroughs."

Brubeck ventured even further afield in another piece that, to his surprise, became a popular hit, his "Blue Rondo a la Turk." Its lush harmonies sounded exotic in the late '50s, while its switches between offbeat rhythms and bona fide swing were like nothing yet encountered in American music.

For "Blue Rondo," Brubeck drew inspiration from a characteristically unlikely source: "I heard street musicians playing in Istanbul," he said in the 2010 documentary film "In His Own Sweet Way." By transforming Eastern harmonies and regional rhythms through jazz, Brubeck hit upon an alluring sound and a signature hit.

But Brubeck's inventions in jazz represent just part of his achievement. He also penned full-fledged ballets and epic choral/symphonic works. The latter took on religious themes and ranked alongside works such as Duke Ellington's Sacred Concerts for their ingenious synthesis of classical, jazz and other idioms.

Brubeck's sprawling oratorio "The Gates of Justice," performed at Anshe Emet SynagogueÖ in Chicago in 1993, fearlessly merged blues melody, Hebraic cantorial singing and chord progressions right out of the African-American spiritual.

To Brubeck, this cross-cultural score – which was commissioned by Rabbi Charles Mintz in the boroughs of New York – had specific political and sociological purposes.

"He came over to the house with two other rabbis, and he suggested I write a piece of music to show the similarities between black people and Jewish people," recalled said Brubeck, in a 1993 Tribune interview.

"The idea would be to show how both groups have been enslaved and dispersed, slandered and harmed, to show that they had more in common than not. …

"For me," Brubeck continued, "the center of the piece is a particular line that was written by Martin Luther King, Jr.: 'If we don't live together as brothers, we will die together as fools.' That's what this piece is about, when you boil it down."

That sentiment drove a great deal of Brubeck's efforts in music and in life. He challenged racial barriers by hiring the African-American bassist Eugene Wright as part of his quartet in 1958 and proceeding to tour the South, a region of the country that did not welcome mixed-race bands. Brubeck and his wife, Iola, in the 1960s created "The Real Ambassadors," a musical that addressed racism head-on and featured Louis Armstrong at a time when the trumpeter was wrongly considered out-of-step with the civil rights era.

"Dave was very aware of race and politics," said trumpeter Jon Faddis. "Back then, you had to go through a lot of stuff, and he stood up and fought for what he believed."

Because of his fame, Brubeck brought that much more attention to the debate.

"He was very important, in that he was hot and brand new and very much in demand," said nonagenarian record producer George Avakian, who recorded Brubeck on Columbia. "He was very much in the forefront, in the eyes of the public."

Moreover, Brubeck used his increasing clout in the '50s to storm the academy, which had been ferociously resistant to jazz. What started out as a few concerts that he and his wife booked themselves quickly morphed into tours and recordings.

"He created the college circuit," said Avakian.