What instrument is the hardest for mastering? And what is the easiest? The answer is unobvious, but it is simple. Of course, all instruments have different construction and each has its own peculiarities. Even principles of sound formation, those are the basis for various instruments (stringed, wind, keyboard, percussive etc), are different. Eventually, we perform diatonic music on all these instruments, so scales, triads, seventh chords and a pentatonic scale are inherent in every instrument (except some percussive). We need years for learning and mastering (cultivation ear skills of performance) the aforesaid diatonic structures on any instrument. The only thing can be guaranteed - every instrument can show the whole harmony of music for you. It seems that piano is the "king" of instruments. Really, eight octaves is an impossible range for many instruments. In the twentieth century ample opportunities of the piano broadened still more. Thanks to the scientific-and-technological advance, the piano can sound like the flute, the violin, the flight of birds, like the passing train, well, like anything. Although technique methods mostly remain the same.
Chords are composed of thirds or you may say, tertian structure is the basic principle of chord construction. There are two kinds of thirds: major (2 whole steps) and minor (1.5 whole steps). Combination of these thirds gives us all the existing chords. If we take major third from the tonic and minor third from the received note, we will get a major triad. Having changed the succession of thirds, minor is the first and then - major, we get the minor triad. If we take two major thirds in succession, it will be an augmented triad. Two minor thirds form a diminished triad. So, there are four subkinds of triads in music: major, minor, augmented and diminished. Major and minor triads are basis of key-tonal (diatonic) music. Augmented and diminished triads always perform an auxiliary part. Chords' tree is an attempt to demonstrate visually the "genealogy" of any chord in music. The Roman numeral I figures the tonic. When we choose the III degree, major or minor, we choose the whole branch, they say in music - key inclination (major or minor). Then the major "branch" is divided into major triad and augmented triad, the minor "branch" is divided into the minor and diminished triads. If we similarly continue the construction (add minor or major thirds to the received triads), then every triad will give us two seventh chords. Thus, "Chords' tree" demonstrates all possible combinations of thirds and, consequently, all possible triads and seventh chords of the tonality. This picture is interactive. When you move cursor to the circle with the name of a chord or a seventh chord, circles change their color. When you press them, a picture opens in a new window; it demonstrates triads or seventh chords and their inversions on the keyboard.
In a few words we will discuss SUS chords. Very often different musical issues suggest different (symbol) notation for suspended chords. From our experience, it is essential to distinguish and mark SUS triads, for example: Csus2 = Csus9 or Csus4 = Csus11. More complicated notation of chords on the SUS basis brings a lot of vagueness to the marking. So, many musicians prefer to write such chords not as Gsus7(9), but Dm/G or not as Gsus+7(9), but D/G. Also instead of Gsus7(11) usually write Dm7/G or instead of Gsus+7(11) use D7/G.
This textbook is written to help pianists to examine kinds of chords and ways of chord's construction in contemporary ("pop", "rock", "jazz") music. It is better to begin with realization, that chords are absolutely identical in all keys. First of all you should examine ways of major and minor triads' construction (in the root position) in all keys. Also you should look through ways of diminished and augmented triads' construction. Practise for some time the identification of major and minor triads (in the root position). Learn few compositions, relying on chord harmonization; you can use Rock Real book or Jazz Real book. Having mastered principles of triads' construction you can start using inversions of triads. Seventh chords should be examined in the same way. Firstly, you should learn (all in their root position) a Major seventh chord Xmaj7, a Major minor seventh chord X7, a Minor seventh chord Xm7, a Minor seventh chord Xm+7, a Half-diminished seventh chord Xm7b5, a Diminished seventh chord Xdim7. Then you can start using inversions of seventh chords.
Some variants of chords' voicings
One of the simplest two handed voicings can be used, for example, to accompany a soloist in a duet.
This is the same voicing with additional degrees - extensions. We use it to brighten the chord..
Here is a left-hand voicing without a tonic. It can be used while improvisation in the right hand with the bass in the accompaniment (a bass line is schematically shown in quarter notes).
Here is a wide voicing without a tonic to accompany a soloistic instrument with a bass guitar.
Here are voicings for the abundant thirteenth chord. A triton substitution can be used in bass in the last bar; this also adds new color to the sound.