What separates Bebop from other jazz styles and subgenres? Which new things did it brought when compared to other jazz of the era? Which are the defining elements of Bebop jazz?
Bebop can in general be characterized by the following stylistic elements:
- fast tempos
- complex, highly syncopated rhythms
- advanced harmony using chords with added higher intervals (9ths, 11ths, 13ths), diminished and augmented chords, etc.
- an emphasis on improvised solos
- using higher intervals of chords, altered scales and chromaticism in improvisations.
For a more in-depth treatment, see e.g the article on bebop on Wikipedia.
It is normally played by small groups. The typical ensemble is formed of two horns and a rhythm section (quintet), but other common sizes ranged from trio to septet. The classic bebop combo consisted of saxophone, trumpet, double bass, drums and piano.
Bebop musicians employed several harmonic devices not typical of previous jazz. Complicated harmonic substitutions for more basic chords became commonplace. These substitutions often emphasized certain dissonant intervals such as the flat ninth, sharp ninth or the sharp eleventh/tritone.
Drastically changed role for the instruments: Bop drummers shifted primary timekeeping duties from bass drum to cymbals and snare, lending the music a lighter, effervescent aura. They began playing multiple overlapping rhythms (polyrhythms).
The focus is in the solos, in contrast with swing where the focus is on the arrangement and the playing of the ensemble.
Is more musically complex than big band swing: more complex chords, harmony, and solos, along with faster tempos.
The priority is listening, rather than dancing. In contrast with swing, where the opposite is the case.
Other characteristics that distinguish it from swing: asymmetrical phrasing, intricate melodies, and rhythm sections that expanded on their role as tempo-keepers.