3. The Essentials of Jazz Harmony and Rhythm What follows is a discussion of jazz harmony and rhythm, including two simple methods for effectively voicing chords. With these formulae and a minimum of technical ability at the piano, any instrumentalist or vocalist can work through the harmony of a composition. Both methods use the major scale as a reference for building harmonies so it is essential that the correct spelling and notating of major scales be thoroughly learned. General Theoretical Principles Scales are built on intervals of seconds played in sequence (ex. A,B,C,D,E,F,G) and chords are built in intervals of thirds, played simultaneously (ex. A,C,E,G). The tone a scale begins on is called the tonic, thus the tonic in C major scale is the note C. The bottom note of a chord is called the root, thus the root of a C major7 chord is the note C. The remaining chord tones relate intervalically down to the root, thus the third tone in a C major chord is E, it being a major third above the root. When defining the individual tones in a major scale, mode of the major scale and the individual tones of a chord, Arabic numerals are used, thus in a C major scale the note C is labeled as 1; D, 2 etc. In a C major 7 chord the individual tones are labeled 1,3,5,7. When defining a chord as part of a harmonic system, Roman numerals are used, thus the chord C Major 7 is labeled the I chord when derived from the major scale of C major. Voicing a chord is the aligning or realigning of the tones within the chord. Not every tone of a chord need be voiced to create a functional chord voicing. Thinking of the process that will lead to voicing chords as a pyramid, at the very top we find the major scale. Next down would come the tonalities created within the scale – its inherent modes (ex. C Ionian; D Dorian; E Phrygian, etc.) Finally we come to the chords built on each tone of the scale using tones from the scale itself. Tonality can be broken down by type: 1. Diatonic Tonality refers to music derived from major and their inherent minor scales. 2. Modal Tonality is based on modes, natural and altered, derived from the major scale. 3. Chromatic Tonality is derived from the major and inherent minor scales, plus the use of frequent borrowing from other major and minor tonalities outside the intended tonal center of a composition 4. Specialty Tonalities based on folk scales and modes such as the blues and pentatonic scales and their variants. Breakdown of Chord Structure Using the Rule of Three 1. The Major Scale 2. Modes of the Major Scale and the Tonal Textures they Suggest (Major and Minor) 3. Chords derived from the Major Scale 16 The Major Scale As discussed earlier, the major scale is built on a series of consecutively ascending and descending tones in intervals of minor seconds (m2) and major seconds M2). The formula is as follows: Intervallic Formula for the Major Scale Tonic – M2 – M2 – m2 – M2 – M2 – M2 – m2 D Major Scale and its Inherent Intervallic Relationships Modes of the Major Scale and the Tonal Textures they Suggest The seven tones of a major scale can be ordered so as to serve as their own tonics, thus creating the modes of the major scale. The sequence of tones is not changed, just their point of origin, thus a mode built on a D major scale but using the note F# as its tonic would now create the F# Phrygian Mode and would read F#,G,A,B,C#,D,E. Note that the intervallic formula changes as well: Intervallic Formula for the Phrygian Mode Tonic – m2 – M2 – M2 – M2 – m2 – M2 – M2 Heard in relationship to a major scale, the tonal texture produced by the Phrygian mode is of a much darker texture. By description it is a minor mode. Having established that within a major scale can be built seven modes, each containing their own tonal texture due to the intervallic realigning, the names of the modes built on the numbered tones of the major scale are as follow: 1. Ionian Mode (built on the first tone of the major scale) 2. Dorian Mode (built on the second tone of the major scale) 3. Phrygian Mode (built on the third tone of the major scale) 4. Lydian Mode (built on the fourth tone of the major scale) 5. Mixolydian Mode (built on the fifth tone of the major scale) 6. Aeolian Mode (built on the sixth tone of the major scale) 7. Locrian Mode (built on the seventh tone of the major scale) 17 Modes Created from the D Major Scale Each individual mode built from the major scale possesses its own distinct tonal texture. The brightest or most major sounding mode built from the major scale is mode built on the 4th tone of a major scale – the Lydian mode; and the darkest or most minor sounding of the modes is built on the seventh tone – the Locrian Mode. The relationship of brightest to darkest modes is as follows: 1. Lydian (Brightest) – suggestive of a major tonality 2. Ionian – suggestive of a major tonality 3. Mixolydian – suggestive of a tonality between major and minor 4. Dorian – suggestive of a minor tonality 5. Aeolian – suggestive of a minor tonality 6. Phrygian – suggestive of a minor tonality 7. Locrian (Darkest) – suggestive of a minor tonality 7th Chords built on Tones of the Major Scale Having created 7 modes within a single major scale, the next step is to create a chord on each tone of the scale using only the tones contained therein. The primary tones 18 in a chord, or the tones that define the chord type are the 3rd and 7th tones of the chord, thus each chord is extended to its 7th degree (ex. 1-3-5-7). A chord can be extended to the 13th degree before returning to the root tone (1-3-5-7-9-11-13 or D-F#-A-C#-E-G-B), but it is important to remember that the key tones, the tones that identify its type are always the 3rd and 7th. The three main chord types derived from the major scale are: 1. The Major 7th Chord 2. The Minor 7th Chord 3. The Dominant 7th Chord Of course, there are other chord types – diminished, half-diminished, augmented suspended and altered, but for the immediate purpose the afore-mentioned types will cover about 90% of the chords we will encounter in the performance of music and should be regarded as the foundation chords for all music. Chords Built on the Tones of the D Major Scale In all 12 major scales the formula is as follows: 1. The I Chord is always a Major 7th Chord 2. The II Chord is always a Minor 7th Chord 3. The III Chord is always a Minor 7th Chord 4. The IV Chord is always a Major 7th Chord 5. The V Chord is always a Dominant 7th Chord 6. The VI Chord is always a Minor 7th Chord 7. The VII Chord is always a Half-Diminished 7th Chord All three have specific functions and are used to establish tonality (ex. the major chord can establishes the major tonality) or lead us to tonality via cadence. Using this principle, minor 7th chords are the most versatile as they straddle both barriers – establishing the minor tonality, but also as leading a chord progression to the establishment of tonality, such as in the II-V-I chord progression which shall be discussed in detail. Chord Syntax By doing simple math we deduce that if there are twelve notes in our tonal system we can build from each note 12 scales. From these 12 scales we produce 36 essential chords. Know these chords thoroughly and the door to the understanding of modern harmony has not only opened, it has exploded off the hinges. As has been stated about 19 90% of the chords encountered on a lead sheet will fall under the major, minor and dominant 7th category. Then why does it seem there are so many other types? The answer lies in correctly identifying the chord then placing it into one of the three categorized types. This means reducing the chord to its lowest common denominator – the position of the third and seventh tones within the chord. The steps involved to facilitate this are: 1. Correct identification of the chord 2. Correct identification of the primary (3rd and 7th) tones of the chord 3. Correct voicing of the primary chord tones Chord symbols can be regarded as musical shorthand. Due to no common formula for chord symbol notation, misreading is a common mistake made by beginners. Let us break down the rules for reading a chord symbol by example: Fm9b5 As simple as this symbol might appear, within is a wealth of information. A chord symbol is read from left to right. Fmin9b5 can be broken into 4 parts: 1. F signifies the root tone (1) of the chord. 2. m tells its type, in this case minor. 3. 9 is the suggested extension of the chord as in 1-3-5-7-9. 4. b5 tells an altered tone within the chord not a part of the major scale from which the chord derives. Proper identification of a chord is essential.