Jackie McLean's unique tone and intonation on the saxophone are frequently commented upon. His approach especially with regard to intonation was surely part of an intentional evolution: in his earliest work with Miles Davis, McLean plays more or less as well in tune as any other saxophonist of the period. So what's the explanation?
In this interview from 1996, McLean offers some insight:
"...even though I never really sounded like Bird, even my first recordings, as hard as I tried to play like him, I still had another quality to my tone that I still have today, which is kind of original - it's mine, you know. And that's another great thing about this music: it's very democratic, everybody can have their own sound, you know. A classical saxophone player, most of the time, they have to get a pitch that is tuned up perfectly to the piano and up to where the piano's A is, and they have to play at a particular intonation to keep it that way. But, and many, and, and many of the, the, the popular saxophone players of today sound alike. I can't tell the difference in all these guys, these current guys and I, it's not that they're playing anything that's so difficult, or so technically different, it's just that all of their tone, the qualities are the same and many of their ideas are the same, you know, very syrupy, sweet tone that they're producing today..."
UPDATE: Saxophonist Nick Biello puts it aptly: "JMac's intonation, even on early recordings, varies from record to record. And on some later records, it's 'in tune.' In an interview (I think it was from Jackie McLean on Mars) he says that he's always struggled with intonation. So I'm not sure if his sharpness was a conscious choice, or if he accepted it and thus made it an organic extension of his sound."