[... Miles Davis's] physical pain improved the music. He had both a wah-wah pedal and a volume/tone pedal hooked up to his horn, which he usually manipulated with his feet. But in Japan, Miles's legs bothered him so much that he knelt down on one knee instead, playing the trumpet with one hand, and using his other hand to carefully work the pedals. Using this method, he was able to achieve a much greater degree of tonal subtlety than if he had used his feet. When he would go into a soft muted solo, with the rest of the band quieted down to a whisper, then drop to a knee and let that pain come through the horn, the effect was heartbreaking.

Miles was always known for the human voice-like articulateness of his quiet solos, the emotional plaintiveness and loneliness crying out like a lost kitten in a moonlit alley. The fact that he was in pain and down on a knee like a pleading soul singer added to the drama of the solo.

I believe Miles was aware of this, and consciously used both the pain and the pose to wring more pathos from the music. […] The band also saw all this, and worked hard to rise to the importance of the occasion.

This was serious stuff, and these performances were some of the finest I'd ever seen him do. I remember once, in Osaka, when he came off the stage after a performance that wove such sublime sadness into the air that I was weeping at the beauty of it. As he handed me his trumpet, I said, "Miles, that had all the pain in the world in it."

He turned to me and smiled.

"It's supposed to," he said.