If the minor forms are used for various minor flavored blues - i iv v - those chords are still tonic, subdominant, dominant.įrom a 'classical' perspective using I IV V is not only totally conventional, it is the surest way to create clearly tonal music. When the chords take a minor third - like a minor third above I7 - the chord is still a I a tonic. When a blues progression uses I7 IV7 V7 the roots are simply I IV V and despite the non-classical treatment of the seventh those chords to have the identities of tonic, subdominant, and dominant. So, while the particular cross relationship on a chord's third is not used in 'classical' style the general concept of cross relationships does exist.īoth of the points above - the handling of chord sevenths and cross relationships on a chords third - have an important point in common: the chord roots do not change and those root's place within the tonality do not change. For example, a blues in C might use an E♭ in a high range above a C7 dominant seventh chord. Blues differs from classical in that it uses cross relationships on the thirds of chords. In 'classical' style cross relationship sometimes happen, like a simultaneous lowered and raised sixth degree in minor. It just isn't an obligatory resolution like in the 'classical' style.Īnother difference is about cross relationships which is the simultaneous sounding of two chromatic variations of a tone. Although when I7 moves to IV7 the 'flat' seventh of I does move to the third of IV in the 'classical' manner.

The resolution is usually a step down to the third of a tonic chord.īlues harmony doesn't treat seventh by that 'classical' convention.

the standard harmony tools can't explain the typical blues sound made by dominant 7 -chords progressionsīy 'classical' music Common Practice conventions the seventh of dominant seventh chords is considered a dissonance that must be resolved.

Harmony assistant sample blues