The real Nathaniel Ayers was invited to view the filming of the scenes at Disney Hall in Los Angeles, but opted on the day to set up his cello and music across the street and continue playing saying "I really got something going here. I think I'm going to stay and play this just a little bit longer." Steve Lopez spoke about this incident in an interview conducted by Dave Davies for National Public Radio's program Fresh Air in April 2008. He added: "I look(ed) across (the street from Disney Hall) and there he is sawing away, as he calls it. And inside this building there are maybe three hundred people, the LA Philharmonic, the cast, the crew, are shooting a movie about his life. And I said to the producer Gary Foster 'You know what Gary, we picked the right name for this thing, The Soloist. There he is.'"
In the scene that Nathaniel Ayers and Steve Lopez attend a rehearsal concert, all the seats are covered with canvas. This was not cinematic imagery; this is actually done in some concert halls during rehearsals to reflect a more accurate sound as if the seats were being occupied.
The scene (during the orchestra's performance of Beethoven) where Nathaniel imagines each color associated with a sound refers to a neurological phenomenon called "Synesthesia" in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway. It is known to have affected many popular musicians, painters and authors like Stevie Wonder, Van Gogh and Vladimir Nabokov.
Lorraine Toussaint (who played Mr. Ayers' mother), LisaGay Hamilton (who played Mr. Ayers' sister Jennifer), and Nelsan Ellis (who played LAMP director David Carter) are all real-life graduates of The Juilliard School's Drama Division. Mr. Ayers was a student in their prestigious Music Division.
Several members of the Lamp Community, a housing and care center for the mentally ill, appeared in the film and attended the Los Angeles premiere and after-party. Nathaniel Ayers is a resident and beneficiary of Lamp.
Originally planned for a November 2008 release date, the film was held back due to Paramount's tightening of the number of films it releases per year and released late April 2009. The trailer continued to run in theaters with November as the release date.
Despite his distrust of two-dimensional images, Nathaniel Ayers did attend the premiere of this film in Los Angeles with his family, who flew in for the occasion. He rarely watches movies or television.
In real life, Ayres had little resistance to the cello teacher and has remained close friends and protégé of LA Philharmonic cellists Peter Snyder (the teacher played by Tom Hollander) and Ben Hong. In real life, Ayres had a lot of resistance to attending the first concert at Disney concert hall.
In the film, Steve Lopez is portrayed as divorced. However, his real life counterpart remains happily married. Lopez said that while having himself portrayed as recently single in the film was a bit weird, it was much more important to him that the film makers captured the themes of his articles rather than absolute facts.
In the scene where Nathaniel Ayers is carrying his stuff to his new apartment, he can be seen wearing over his costume a large yellow necklace which says America and shows a logo. America is the name of one of the most popular soccer teams in Mexico.