Duke Ellington’s big band sounded like no other because of his unique approach to composition. In jazz’s 20th century heyday, a composer usually started by writing a song, and then a random group of musicians performed it. Ellington flipped that script by starting with the musicians. He gathered a group of rare individuals, crafting the music around their idiosyncrasies. That gave the likes of “Mood Indigo” and “Satin Doll” their special character: passionate, playful, often profound.