Keeping this in consideration, why are seventh chords used?
Because the interval between the 3rd and the 7th creates a diminished 5th, a very unstable, dissonant interval that practically begs to be resolved inwards, to notes which just happen to be the 1st and 3rd degree of the tonic chord. Use this chord to create a strong V to I feel.
Additionally, why is the 7th chord diminished? Because these chords have no leading tone in relation to the chords to which they resolve, they cannot properly have dominant function. They are therefore referred to commonly as non-dominant diminished seventh chords or common tone diminished seventh chords (see below).
One may also ask, what chords are used in jazz?
Basic Jazz Chord Progressions
- Major ii-V-I. The major ii-V-I is easily the most important chord progression to get a handle on when it comes to jazz.
- Minor ii-V-i. This chord progression has the same function as the previous major ii-V-I, but of course is in a minor key.
- Major I-vi-ii-V.
- Minor i-vi-ii-V.
How do you use a 7th chord in a progression?
To play a Dominant 7th, take a major chord and add a minor 7th. That's 7 intervals, but the minor note, which is a semitone lower, flat note. For C Major this would be C – E – G – Bb. Dominant 7th chords are traditionally common in Blues music, and therefore Rock music too.
