I often find myself trying to explain to people why I love listening to Jazz. Most people either don’t know much about it or don’t like it at all, especially if it’s “modern”. The trouble is, explaining why it’s so hard to play jazz doesn’t usually make people want to go and listen to it. “There’s no proper tune” and “It’s just noise” are just a couple of the comments I heard in a pub a few weeks ago when somebody put a Miles Davis track on the internet jukebox.

It’s partly a matter of language, of course. The most exquisite Japanese poetry probably sounds like noise to a Westerner who can’t understand the language. When it comes to jazz, even if you do know a bit about the music you’re by no means guaranteed an easy listening experience. But, played at the highest level, with a driving rhythm section and a star soloist improvising through a constantly shifting pattern of harmonies, there’s no music to match it for sheer white-knuckle intensity.

Far from being “just noise”, jazz is a tightly disciplined musical form. The freedom given to the soloist to create their own melody comes in fact at a very high price because the melodic line of a jazz solo must constantly recalibrate itself in relationship to the harmonic changes going on beneath it. The chord progression within which the original melody was embedded provides the soloist with the challenge of playing something that fits as well as being new and interesting to listen to. Usually the actual tune is played only briefly at the start and thereafter becomes pretty much irrelevant until recapitulated at the end of the performance. What really matters to a jazz soloist is not the original melody but the chords.

Each chord establishes a tonal centre and a related scale that furnishes a reference frame in the space of possible musical notes. When the rest of the band makes the chord changes the soloist must transform to a different coordinate system. The progression of chords as the tune unfolds thus has the effect of pushing and pulling the soloist in different tonal directions. A great jazz solo requires strict adherence to this framework and it imposes tremendous discipline on all the musicians involved.

In a slow 12-bar blues the gravitational effect of the relatively simple chord pattern is especially strong, which is no doubt why it has such a powerfully expressive effect when the soloist plays a “blue note” such as a flattened fifth on top of major scale chords.

In more complicated tunes keeping your place within the constantly shifting harmonic framework is a real challenge, especially if the chord progression is complicated and especially at fast tempi in which the chord changes go flying past at a rate of knots. Such numbers turn into a rollercoaster ride for both musicians and audience.

It’s not just the speed of fingers that makes great soloists so electrifying, but their astonishing mental agility. I remember seeing the great saxophonist Sonny Stitt at Ronnie Scott’s club in London playing the jazz standard How the Moon. Nothing unusual about that because it’s part of the jazz repertoire. The thing was, though, that he played 12 choruses, each one in a different key. How he managed to keep track of everything is completely beyond me. I wasn’t the only one in the audience shaking his head in disbelief.

Giant Steps by John Coltrane is an example I posted a while ago of a supreme piece of high-speed improvisation, and I thought I’d follow it up with this wonderful performance in which the legendary Charlie Parker plays an extended solo, very fast.

The tune is in fact a variation of a 1930s hit called Cherokee. Most popular tunes have a 32 bar basic format of the type AABA, with B representing the bridge or middle eight. Cherokee has a similar structure, but is 64 bars long. Its chord progression is both complicated and unusual, with lots of changes to remember especially in the (16-bar) bridge which is fiendishly difficult to play. This makes it fertile ground for improvising on and it quickly became a standard test vehicle for jazz soloists and a yardstick by which saxophonists in particular tended to measure each other’s skill.

During the bebop era it became fairly common practice for musicians to borrow chord sequences from other tunes. Many Charlie Parker pieces, such as Anthropology, are based on the chords from I Got Rhythm for example. There’s a famous story about a recording session involving Charlie Parker during which the band decided to do a version of Cherokee (i.e. using the chord sequence but with a different melody). During the take, however, they absent-mindedly played the actual melody rather than playing something else over the chords. There was a cry of anguish from producer in the control room who had hoped that if they stayed off the actual tune of Cherokee he wouldn’t have to pay composers royalties and the performance ground to a halt. Shortly after, they did another take, called it Ko-ko and it quickly became a bop classic. This is a later version of Ko-ko, played live, during which Bird runs through the changes like a man possessed. What it must be like to be able to play like this!