Then in his highly instructive solo — with its exhilarating mix of upper register skids and fast vocalisms — Bluiett promptly showed us there's no real difference between free and in the tradition music — at least, not when he and Kahil El'Zabar are playing.

At one moment, El'Zabar's cyclical kalimba-and-voice moans, his jazz traps, hand drumming and ankle bells, occupied the foreground; the next moment, it was EL'Zabar who backed up Bluiett's forward leaping intervals and downright funk.

As the star duo — shone — they consistently played the inner music of "Take The A Train", but they had earthly fun, too. When the hunched over El'Zabar vocalized, "Bye-bye baby, bye-bye", Bluiett immediately joined in with some 'stage business' and turned his back to the audience, and waved 'Bye-Bye' with his left hand.

End of story.

El'Zabar's voice and kalimba grooves felt good all night, and together with Bluiett's rooted yet mobile baritone, this relaxed duo offered a sound experience that was both healing and somehow fortifying.

The only bad note was the woefully small audience this night. Whether it was the weather, or a severe case of market segmentation, or a case of simple inattention, no one will ever know.

But I myself received a beautiful lesson this night.

The lesson is that the blues is a wonderful, almost infinite tonal 'system', so it needn't be a question of leaving the blues behind in order to go beyond in music.

Of course, I say this after an evening of music from Kahil El'Zabar and Hamiet Bluiett, these trance masters, these messengers of Afro blue.