Perhaps one has to rely on ideas that pick up more on the experience than on any attempted academic definition, with phrases such as Whitney Balliett's "Sound of Surprise" (1961), which he elaborated on to describe jazz as "a highly personal, lightweight form - like poetry, it is an art of surprise - that, shaken down, amounts to the blues, some unique vocal and instrumental sounds, and the limited, elusive genius of improvisation (some of it in the set forms of jazz composition)."
Of course, such a description asks as many questions as it answers - what are the "blues" for example, what is improvisation, and how do composition and improvisation live and work together?
John Fordham in his masterly 1993 book entitled simply "Jazz", captures the nature and spirit of jazz better in his simple sentence: "It is the sound of the skipped heart-beat, the caught breath, the sudden smile."
There is one word which appears in both of these descriptions or attempts at a definition of jazz, that appeals to me as saying something meaningful about the music, and that is the word "sound". Jazz to me is about sound, it's about the expression in sound of an authentic response to life, all of life, with its ups and downs, its elation and heartbreak, its moments of relaxation and sweaty hard labour, its hate and its love.
Writing about Miles' Kind of Blue album, Fordham in his introduction writes about an example of that sound:
"It comes deceptively after a soft, padding double-bass statement of the theme 'So What'. As it ends, Miles Davis's trumpet solo begins, with only two notes, the second an octave below the first. The first haunting sound hangs on its own in an otherwise empty space for a second that seems to go on forever. As it dips, the drummer suddenly hits his cymbal with a single reverberating blow that erupts like a flare over a twilit scene, and the jangling rivets sizzle on as Davis's horn eases nonchalantly into swing. It sounds both inevitable and astonishing at every new hearing."
I love Jazz and with this studio is just my tribute to music!