¹ A few examples of predominantly improvised film scores throughout cinematic history are Miles Davis's score for Louis Malle's Elevator to the Gallows (1958); Mark Isham's score for Alan Rudolph's Afterglow (1997); and Bill Kirchner and Marc Copland's score for Marlyn Mason's film short, The Right Regrets (2013).

² Alejandro González Iñárritu, quoted in Lorraine Ali, “Antonio Sanchez's Soaring Beat Takes Flight in Birdman,” Los Angeles Times, 9 December 2014, http://www.latimes.com/entertainment/envelope/la-et-mn-birdman-antonio-sanchez-20141209-story.html.

³ Ibid.

⁴ Alejandro González Iñárritu, liner notes to Birdman or (The Unexpected Virtue of Ignorance), Milan M2-36689, CD, 2014.

⁵ In addition to Sanchez's original score are six classical pieces at the end of the soundtrack album: Mahler's Symphony No. 9 in D: Andante Comodo; Tchaikovsky's Symphony No. 5 Op. 64 in E minor: Andante Cantabile; Mahler's Ich Bin Der Welt Abhanden Gekommen; Ravel's Passacaille (Trés Large); John Adams's Prologue: Chorus of Exiled Palestinians; and Rachmaninov's Symphony No. 2 in E minor, Op. 27: Allegro Molto. In the film, these pieces function as the score for Riggan Thomson's play-within-the-movie. While heard as underscore, they have a diegetic function. I must also note that three of Sanchez's original score tracks—“Get Ready,” “Fire Trail,” and “The Anxious Battle for Sanity”—briefly contain additional music by Víctor Hernández Stumpfhauser and Joan Valent edited into the recording of Sanchez's improvisations.

⁶ Matt Collar, “Birdman (Original Motion Picture Soundtrack),” AllMusic, 14 October 2014, http://www.allmusic.com/album/birdman-original-motion-picture-soundtrack-mw0002796520.

⁷ Fortunately, a plethora of interview-based articles have been released in the aftermath of Birdman’s critical success, in which Sanchez has offered his own perspectives on the soundtrack development. They are too numerous to list here, but may be easily located through an Internet database browse.