Chord progression (half note open guitar chords) for the widely recorded ragtime influenced song written in 1923 by Jimmy Cox, "Nobody Knows You When You're Down and Out". It features chromaticism through chains of secondary dominants (III = V/V/V/V = V/vi, VI = V/V/V = V/ii, II = V/V, and V) and a secondary diminished seventh chord (viio7/V=♯IVo7).
Giovanni Benedetti's 1563 example of a comma "pump" or drift by a syntonic comma (21.51 cents) during a progression. Common tones between chords are the same pitch, with the other notes tuned in pure intervals to the common tones.
Chord progression of La Folia theme, a common harmonic pattern in baroque music. After chord notation provided by User:Hyacinth at en:File:Later Folia.png. Self-made with Lilypond
Secondary dominant with barbershop seventh chords. V/V - V - I in F major (G7-C7-F). Derived from [1]. In just intonation. Sevenths are harmonic sevenths, and the F in the first measure is 27.26 cents lower than the F in the third measure. Pitch bend matches intervals.