The real people in the movie

Of course Ray Charles was real, but many of the other people in the movie are famous, too. For instance David "Fathead" Newman: But Quincy Jones is even more famous: According to Wikipedia he is

an American record producer and musician. A conductor, musical arranger, film composer, television producer, and trumpeter. His career spans five decades in the entertainment industry and a record 79 Grammy Award nominations,[2] 27 Grammys,[2] including a Grammy Legend Award in 1991. He is particularly recognized as the producer of the album Thriller, by pop icon Michael Jackson, which has sold more than 110 million copies worldwide,[3] and as the producer and conductor of the charity song “We Are the World”.

It's hard for me to think of Quincy Jones not being old enough to get into clubs, but everyone is young once. Only the lucky ones get to be old. Here he is on the Colbert Report:

The Colbert Report	Mon - Thurs 11:30pm / 10:30c
Quincy Jones
www.colbertnation.com
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Ahmet Ertegun was a real person, too, and did a lot to promote American music, not just Ray Charles:

I think I should say something about Jazz, Gospel, Soul Music and Hokum Blues, but maybe I'll do that after you've seen the rest of the movie.