Trumpeter and Composer Miles Davis (1926-91) was a hugely influential figure in the development of jazz. He established several new trends that became distinct styles in their own right, including modal jazz, jazz-rock fusion and cool jazz. Cool jazz was a style with revolutionary characteristics of an increased degree of complexity to include fast tempi and driving rhythms, instrumental virtuosity and improvisation based on the combination of harmonic structure and melody. Vast chord extensions became more common to include added 7th’s, 9th’s and even 11th’s which suited the chromatic and highly decorated melodic lines that often used wide intervals and many sudden changes of direction.Cool jazz was developed in the early 1950’s and was associated with an intellectual approach of its theory. In the 1950’s a younger generation of jazz musicians forged this new style and Miles Davis was perhaps the most prolific and profound composer of the medium. It also became more common for black musicians to be allowed access to recording studios. The previous generation’s maverick’s such as Charlie Parker and Dizzy Gillespie were highly influential characters for Miles Davis as he decided to study informally with them after abandoning his course at Juilliard. However, Davis was not naturally suited to the rigorous trumpet playing of the Bebop era as he preferred solos in the middle range of the trumpet with soft, legato articulation. This experience nevertheless gave Davis insight into the key harmonic and chordal innovations that would be the cornerstones of his new music and he advanced these various techniques with a more freewheeling, intricate and often arcane approach.Having come closer to the realisation of his new style he met an arranger called Gil Evans towards the end of the 1940’s. Together they resulted in the creation of the Miles Davis Nonet. By 1959 they had become a sextet but still setting a ‘gold standard’ for jazz performance. As a soloist; Miles began to explore a different range of moods and emotions. Davis sought to open up standard jazz harmonies to express a personal atmosphere. His experiments led to new harmonic structures and variations of cadence-orientated progressions and resulted in the creation of his two albums, ‘Milestones’ and ‘Kind of Blue’. This began the development of ‘modal jazz’.Notation / Scoring of Miles’ works was usually confined to only the briefest of sketches, sometimes just a fragment of a scale as an indication of the direction of the music, as was reportedly the case of Davis’ recording on “Kind of Blue”. This was also a feature of his “All Blues” and the emphasis therefore on solo improvisations with minimal arrangement.Of particular interest is Davis’ “Move”. A key feature of this is its use of 32-bar ‘AABA’ popular song form. Using chord sequences from popular songs as a basis for compositions became a common trait and Gershwin’s “I Got Rhythm” was a common model as it provided good ground for improvisation. Strictly following suit is Davis’ “So what” using the AABA song structure after a rubato introduction, and conventionally leading to a series of solo choruses An innovative modification of typical form can be seen in “All Blues” which is essentially a 12-bar blues in G and its triple metre was very unusual for jazz. The head-solos-head format used here is distinctive of small modern jazz groups. Miles successfully obscures the original pulse, metre and harmonic rhythm with changing phrase lengths, syncopation and persistently contrasting accents.The rhythm section during this era, as usual, carried the weight of harmony and rhythm. Drum patterns were highly complex with polyrhythmic styles and an ability to maintain a quaver beat on hi-hat, with bass and snare accents. In “Move”, drummer Max Roach, already well known for his almost ‘melodic’ drum solos, concentrates mainly on snare drum and tom-toms but uses cymbal splashes at the ends of phrases as a link. Still common were the walking bass lines, off beat quaver movement and uncluttered swing time styles. Pianist ‘Bill Evans’ was well accustomed to using an increased chord vocabulary focusing on punctuation to highlight changes which then developed into more complex polychords.Revolutionary changes were also made to the melodic styles and structures. As improvisation was frequent, individual proficiency was crucial. At the turn of the century, harmonies were enriched through the successive inclusion of higher members of the overtone series, resulting in the extensive use of ninth, eleventh and thirteenth chords and beyond. Cool jazz then prevailed with the use of higher harmonics creating an even more dissonant effect. Music by Miles Davis made numerous references to this. In the thematic material of “All Blues” the trumpet moves largely in parallel to the alto sax line adding sevenths and ninths where, when reaching the dominant, a D7#9 chord is produced – well known to rock guitarists as ‘the Hendrix chord’. Miles was famous for his use of dissonance and modes with considerable motivic development using chromatically inflected harmonies which often contrasted with other musicians in the band. Melodies were also alter chromatically such as by using a sharpened 9th or flattened 13th and put alongside diatonic harmony. The once dazzling flattened 5th now became just another blue note.The individual contributions of each musician are the main phenomenon of this music. Miles Davis himself offers an impressive individual quality. He preferred the middle range of the trumpet and his broad articulation and generally legato style with little vibrato gives a coolness to the sound created. Some other technical brilliance shown is his ability to play very subtle tonal inflections. He occasionally falls off the pitch of a note like in “Move”, and uses ghost notes and half-valving. In “All Blues” Davis uses a Harmon mute for his solo. This metallic mute gives a warm sound when used by Davis and is a hallmark of his distinctive timbre. Alto Saxophonist Julian ‘Cannonball’ Adderley adopts a much more chromatic approach and he embraces quaver, triplet and semiquaver runs such as in “So What”.Adderley was a virtuosic saxophonist and he covers the whole range of the instrument, moving swiftly from one extreme to the other, contrasting to Davis. John Coltrane on tenor sax offers a much more forceful characteristic to the ensemble playing loudly in the upper registers like in choruses 11-14 of “All Blues”. He greatly extended the technique for tenor sax with dextrous and repeated development of short melodic fragments at high speed to give intense bursts of activity with pronounced pentatonic quality. He plays across the beat so is much less rhythmic than Miles or Adderley. The ambiguous front line of the Miles Davis Nonet (tuba, baritone sax and French horn) made song arranging rather challenging for piano player John Lewis but the unconventional mix of the different instrument styles gives a light airy sound to the prominent contrapuntal textures of “Move” and the overall ensemble works well.”All Blues” in contrast to the other jazz works mentioned is an extended performance of some 11minutes. Written 10 years after “Move”, it saw the advent of the 12-inch LP record which offered 20mins of playing time per side. Jazz improvisers could then perform in the studio as they would in a live performance, enabling them to develop their ideas further than previously and multiple microphone placement permitted ensembles to be ‘balanced’ in the studio.It is evident that at the end of the 1940’s Miles Davis was beginning to create a new form of jazz music and his expansive ideas are clearly expressed in “Move” and by 1959 he had sourced a ground-breaking transformation for the world of music with “All Blues” and “So What” which resulted in the creation of a sophisticated and very different new style. Miles Davis continues to be one of the most prolific and profound composers of jazz music.