This is chord progression typical for classical music for all keys with example in basic C major and A minor key

1. Chord progression in Major key: (example of C major)
1) Tonic can be changed with Submediant (vi) in classical music and with Mediant (iii) in some modern music;
2) Dominant can be changed with Leading-tone chord (viio
) in classical music and with Mediant (iii) in some
modern music;
3) Subdominant can be changed with Supertonic chord (ii) in classical music and with Submedinat (vi) in some
modern or classical music;
4) T (sphere) S (sphere) D (sphere) - in classical music
5) Leading-tone chord (viio
) and Dominant chord (V) makes Dominant7
(D7
or V7
)
6) Subdominant (IV) and Supertonic chord (ii) makes Supertonic7
(ii7
)
7) The common root of Supertonic7
(ii7
) is first root (ii
6
5) and in Cmajor it will be: F-A-C-D or short Dmin7
/F or
F6
(F major with added sixth tone)
Diagram: dominant sphere
Leading-tone chord (viio
- B dim: B-D-F)
│ = Dominant7
(V7
or D7
) - in C major: G7 (G-B-D-F)
Dominant (V - G major: G-B-D)
│
Mediant (iii - E minor: E-G-B)
│ tonic sphere
Tonic (I - C major: C-E-G)
│
Submediant (vi - A minor: A-C-E)
│
Subdominant (IV - F major: F-A-C)
│ = ii7
(D-F-A-C) common root Dmin7
/F = F6
(F-A-C-D)
Supertonic chord (ii - D minor: D-F-A)
subdominant sphere

2. Chord progression in Minor key: (example of A minor)
1) There are 3 types of minor scales: natural (with same key signatures like parallel major scale, example of
Am-C with tones “F” and “G”), harmonic (with leading-tone – viio
– tone”G#”) and melodic (with leading-tone
– viio
– tone”G#”, and VI+
– tone”F#”);
2) Tonic can be changed with Submediant (VI) and with Mediant (III) if the type is natural minor scale;
3) Major Dominant can be found in harmonic and melodic type of scale and it can be changed with Leading-
tone chord (viio
);
4) Minor Dominant can be found in natural type of scale and then melody sounds like in aeolian mode
5) Minor Subdominant can be changed with Supertonic chord (iio
) and with Submedinat (VI) in natural and
harmonic type of scale;
6) Melodic type of minor scale is common for ascending melodies with raised VI, and VII step (tones “F#” and
“G#” in a melodic minor). In that case VI raised step will be harmonized with Major Subdominant (S or IV, in
A- melodic minor “F – A – C”. VII raised step will be harmonized with Major Dominant (D – V “G – B – D” or
D7
- V7
“G – B – D – F”
7) Descending melodies are often in natural minor scales and then we use Minor Dominant and Subdominant
8) In classical music cadences are often in harmonic minor scales with this chord progression:
t (sphere) s (sphere) D (sphere) t
9) Leading-tone chord (viio
) and Dominant chord (V) makes Dominant7
(D7
or V7
)
10) Minor Subdominant (iv) and Diminished Supertonic chord (iio
) makes Half-diminished Supertonic seventh
chord (iio7
)
11) The common root of Supertonic7
(iio7
) is first root (iio6
5) and in A-minor natural and harmonic it will be: D-
F-A-B or short Bo7
/D or Dm6
(D minor with added sixth tone)
Diagram of three types minor scales
Minor dominant ( v − E-minor: E-G-B)
│
Minor tonic (i – A-minor: A-C-E) natural minor
│
Minor subdominant (iv − F-minor: D-F-A)
Major Dominant ( V− E-Major: E-G#-B)
│
Minor tonic (i – A-minor: A-C-E) harmonic minor
│
Minor subdominant (iv − F-minor: D-F-A)
Major Dominant ( V- E-Major: E-G#-B)
│
Minor tonic (i – A-minor: A-C-E) melodic minor
│
Major Subdominant (IV − F-major: D-F#-A)