Main Difference Between Regular Music Theory and Jazz Theory
Regular music theory and jazz music theory have similar goals but use different terminology. This can be confusing, but even within traditional theory, different terms exist depending on what side of the world you live. The process of learning the difference involves learning the terminology for both styles. Breaking it down to the simplest elements, jazz music is just shorthand for classical theory. This is important in jazz because performers have to improvise and don’t have time to think about Roman numeral relationships and extended analysis. Learning the terminology for both styles will make you a better musician.
Jazz musicians often cite a large amount of chords available in jazz music that are not available in classical music. Again, this is a misunderstanding. Jazz music makes use of flat five chords, called diminished chords in classical music. The seventh chords used in classical music exist in jazz music as well. The only difference is the notation. Think of jazz as shorthand for classical music. Since jazz musicians have to play and realize chord changes quickly, the chord’s name is notated. For instance, a I chord in classical music might be written as a C in jazz music.
Sevenths and Extended Chords
There are several ways of creating jazz shorthand, and jazz players must learn all of them. A minor seventh chord is a C-7, Cmin7, Cmi7 or Cm7. Classical music would more than likely use a Roman numeral to represent the scale degree as opposed to spelling out the actual chord name. For instance, in the key of C, a major-minor seventh chord on G is V7. In jazz music, there are also 9th, 11th and 13th chords that essentially have extra tones added on to the top of 7th chords. Classical music was using 9th, 11th and 13th chords early on and can be seen in the symphonies of Gustav Mahler and several other Romantic period composers.
Many jazz musicians assert that the “blue note” is unique to jazz. However, this too has precedence in classical music theory. The “blue note” is typically a slightly flattened 3rd, 5th, and 7th. However, these semitones exist throughout history and have their basis in the portamento of the violin. Composers of the early 20th century also cited the possibility of writing entire compositions using semitones. Arnold Schoenberg even invented a system for composing with these semitones.
Chord Changes and Figured Bass
Jazz music makes use of chord changes. In baroque music, there is an identical concept referred to as figured bass. Figured bass method instruction occurs in many universities, although it is mostly outdated. With figured bass, shorthand appears beneath the staff. This shorthand tells the performer what chords to use and the voicings. The lowest pitch is written in the score with figured bass, such as a 6/4 chord. Each number refers to a note the distance away from the bass note. For instance, a 6/4 chord on D would have the pitches D-G-B. While in jazz, the chord quality is spelled out. Instead of spelling out the numerals 6/4 you would have a G/D written in the score. This indicates that it is a G major chord with the D in the bass. Again, both of these chords exist in classical music theory, but jazz and classical theory use different notation methods.
Both classical and jazz music use the same type of cadences. While classical music will usually refer to these cadences with simple terminology such as half, full and plagal cadences, jazz music usually spells these cadences out. For instance, a half cadence in jazz would be written out as a ii — V — I cadence in jazz. Aurally, they are the same thing, but there is simply a different terminology used to express each term.
Jazz and classical theory use major and minor scales as well as modal, octatonic, whole-tone and pentatonic scales. The blues scale is often quoted as belonging specifically to jazz, however, it is just a modified diatonic scale or pentatonic scale. Remember, that a diatonic scale is essentially the white keys of the piano from C to C while a pentatonic scale is a 5-note scale written diatonically. The six-note blues scale is a minor pentatonic scale with a flat fifth that sometimes enharmonically spelled as a flat fourth. The seven-note blues scale is a natural minor scale with a lowered 5th and raised 6th. The nine-note blues scale is a major scale with an additional half step between the 3rd and 4th scale degree and the 7th and 8th scale degree. Carl Orff is a famous classical composer that used pentatonic variants of these scales often.
Originally published at https://www.uremusic.org.