Emotions and Jazz Rhythms
Why do we want music to affect us emotionally and what has rhythm got to do with it? Well, people are gluttons for emotion. That's why we watch Holby City on television, or watch a Hammer Horror Movie, to experience emotions which can act like a drug, and in fact do produce chemicals in our brain and body that are effectively drugs. African drumming, with no melody, is charged with emotion, and many jazz bands include a drummer. Then there's the question of why do humans want to experience these emotions? Through evolution, the brain has developed emotions as a way of focusing the organisms attention onto what is necessary, whether it's saving it's life through the emotion of fear, making sure that the humans offspring are cared for because of the emotion of love, making sure that humans reproduce themselves by creating the feelings and emotions of sexual attraction, whatever emotions we look at, we are only alive today because our ancestors were able to experience those emotions. Experience those emotions have saved the lives of our ancestors, made them have children and look after the children well, and all those who did not experience those emotions in the right way no longer exist, didn't have children of their children failed to survive, and are now extinct. This is what evolution is about.
So the human mind, or at least the minds of the humans that are alive today and haven't become extinct, are susceptible to emotions, crave emotions, thus crave the sounds that engender those emotions, whether it be the sounds and inflections of natural language, or the sounds and inflections of music. Without all this, the music industry wouldn't exist, I wouldn't be in business with the Midsummer music agency hiring out string quartets, jazz bands, ceilidh bands and barn dance bands for weddings and parties, The Beatles and the Rolling Stones wouldn't have made their multimillions and had whole populations clamouring to hear their music, to get a fix the emotions of their music created.
So it is with jazz. Jazz was the outpouring of black Americans who were imprisoned by slavery, treated as the scum of the earth by their white rulers, living in misery and dejection for much of their existence. It was music, sometimes to reflect the emotions they were feeling and express their emotions to others, emotions of misery and dejection, The Blues. Other times it was music to create the emotions that they were missing from other sources, emotions of joy and happiness, that was jazz. Other times to create the emotions that would back up their hopes for a better future, that was the jazz music of spirituals.
So having rambled around the psychology of music, let's get back to the basics of jazz. I was saying the jazz is not a geometrical mathematical form, although it is analysed by musicologists as such. A great deal of the subtlety of the form of hot jazz improvisation cannot be expressed in musical notation. This is quite different, as I've said before, the classical notation where the dots were written by Joseph Haydn convey probably 90% of the music's intention. In jazz, the new musical notation, if it is notated at all, would only express perhaps 50% of what that music was about. But 50%, is still a lot better than nothing, so it is very worthwhile.
This is something I've often discussed with those folk musicians who cannot read music and can only play by ear, or the jazz musician who is really good at improvising and can't understand the classical musician who has to have their dots to play music tour. Although musical notation doesn't convey everything, it is a way of passing on a fast amount of information, an amount that cannot be kept in the human brain. Thus the musician who can read music has the whole world of music to double with, though they may not be able to play all kinds in their true manner. Conversely, the musician who cannot read musical notation, may well play their narrow form of music perfectly, but they will forever be limited to their local area. As is normally the case, it's horses for courses.
So a great deal of the subtlety of hot jazz improvisation is impossible to express in musical notation. In its detail it is is free and unpredictable as the emotions of the musicians who are creating it at that very moment. But, even at its freest, it is remarkable how often jazz performances exhibit characteristics that can be measured and are recognisable elements. That this isn't surprising really. Going back to speech, each winner of the Booker Prize, has written a book that is considered to be unique and special, indeed just about every book that is written as a large element of uniqueness to it, yet they all written with the 26 letters of the alphabet. Those letters are combined in a particular language, say the English language, into a dictionary worth of words, but most books are written with just a very small subset of that dictionary worth of words. Words that are used outside that small subset often used for the effect of surprise or emphasis. So it is in music, whether it is a Beethoven string quartet, an Irish ceilidh tune or a jazz number. Most of the elements are recognisable as being part of a language, they are put together in remarkable new ways.
Thus all manifestations of hot rhythm are not precisely alike. For example, each musical instrument has its own special abilities and limitations, and this has profound effect on what the musician plays. For example, as a violinist I can be totally mystified by some guitar rifts in pop music, which seem entirely meaningless to me, yet whole swathes of the population will hang on every note. This is because guitar rifts are typically developed around the string tuning and fingering of a guitar, which is in fourths, whereas violin music is developed around the fingering and tuning of that instrument, which is in fifths. A very different kettle of fish.
Jazz bands are usually divided into 3 categories of instrument, the brass, the reeds and the rhythm section. Brass includes trumpets, trombones, tubers et cetera. Reeds include clarinets, saxophones, oboes, and typically though incorrectly, flutes which do not have a read. In classical music rather than the reeds they would be referred to as woodwind, although even this is a bit archaic as flutes are no longer made of wood, metal construction, only Irish and other folk flutes or baroque flutes onward. The rhythm section includes drums as one would expect, but piano, guitar, banjo and peculiarly the double bass tend to be included under this heading.
There's more to this subdivision than just categorising instruments, it's also a categorisation that reflects the differences in improvisation techniques of the musicians. The "hot" intimation of a jazz trumpeter is quite different from those of a jazz saxophonist. Trumpeters style of play tends to be more lyrical and singing and less precise and ornate than a saxophonists. A jazz guitarist will be much more concerned with courting rhythm in their improvisation.
The trumpet and trombone's creatively extreme emotions of a jazz ensemble, and because of the way the notes can be bent and slurred between precise notes, particularly with a trombone with the slider, the result is much more like the singing of the human voice. The inflections of the music are much closer to song and natural speech (reference my comments about natural speech and music, above), thus the trumpeter and trombone player is the closest to be speaking and singing and experiencing emotion or transmitting emotion, through their music.
To help with this, they have the highest dynamic range, other than perhaps the piano. Is also possible to dramatically alter the colour and tonality of the sound, particularly when using the instrument in conjunction with the mute, something which is much more limited in a reed instrument where the player has far less influence over the creation of the vibration that excites the note, which is much more a function of the physics of the reed itself. Going beyond the vibration of the air column in the instrument itself, the vibrations on a brass players instrument interact with the musicians own body and the air cavities of mouth throat and lungs. The lips function much more simulated vocal chords of singer, allowing flexibility and responsiveness.
Jazz trumpet and trombone solos tend therefore to have a huge rhythmic and dynamic freedom that cannot be achieved the same extent with other instruments. The music has inflections that resemble speech with the reading of prose, and as I mentioned earlier on with the bowing used in Irish fiddle music following the accident styles of Irish speech, so the inflections of a true jazz soloist resemble the style of Afro-American speech. So, ascending runs and crescendos are less frequent than in classical music. Explosive attacks and sfortzando's are followed by diminuendos and melodic downward movements. (I was just thinking about the Brummie accent, with its characteristic downward inflection at the end of every sentence, giving the impression that the speaker is suffering from severe depression. I'm not aware of any specifically Brummie folk music, but if there was it would certainly have to end every musical phrase with the downward cadence of a couple of tones, and a shop diminuendos.
The reeds, or woodwind section of the jazz band tends to play more lyrically, playing in what would be considered a more classical Western style, not because of intention perhaps, but because of the abilities and limitations of the instruments. So whilst in a jazz band, the brass can produce the rhetoric and the exclamations, the melody tends to lie with the reed section. They tend to be somewhat more civilised in their performance, though not necessarily so for the saxophone section, which can make some quite exclamatory and rude sounds. Woodwind solos tend to have a more conventional musical form. If you listen to brass Solo out of context without the rest of the band, it will probably mean very little musically. Do the same with the reed instrument, and you probably would recognise what they were playing as a tune, even though divorced from the jazz band that it was a part of. Solos tend to be very notey and flashy.