Chord Terminology Question

[caminium]

Is there a name for the relationship between the chords of a triad? For example; Cmaj7, Em7, G7. Or G7, Bmin7b5, Dm7. I call them 'cousin chords' but didn't know if there's actually a real name for it.

[dconeill]

Is there a name for the relationship between the chords of a triad? For example; Cmaj7, Em7, G7. Or G7, Bmin7b5, Dm7. I call them 'cousin chords' but didn't know if there's actually a real name for it.

Your terms are a little off. A triad is a chord containing 3 pitches; none of the chords you listed are triads. They all derive from the harmonization of the major scale by thirds, i.e., for each note in the scale, put the pitch a scale third above the note in question. If you stack a total of 3 notes, that's a triad; sometimes four-note chords are called tetrachords.

My memory is failing me for a group name for these chords; I suppose you could call them chords from the harmonized major scale; perhaps someone else has a better name.

For example, in the key of C:
Scale degree Root / third of chord / fifth of chord / seventh of chord / intervals / chord name
I C E G B / Maj3 Min3 Maj3 / major 7th
ii D F A C / Min3 Maj3 Min3 / minor 7th
iii E G B D / Min3 Maj3 Min3 / minor 7th
IV F A C E / Maj3 Min3 Maj3 / major7th
V G B D F / Maj3 Min3 Min3 / dominant
vi A C E G / Min3 Maj3 Min3 / minor 7th
vii B D F A / Min3 Min3 Maj7 / half-diminished 7th, aka minor 7th b5

This pattern holds true for any major scale - the I chord is a Maj7, the ii chord is a Min7, and so on.

The chords that derive from harmonization of the harmonic minor and melodic minor ascending scales are different, but easily derived in the same way. E.g., in A harmonic minor, A B C D E F G#
i A C E G# / Min3 Maj3 Maj3 / minor natural 7
ii B D F A / Min3 Min3 Maj3 / minor 7 b5
and so on

For a complete explanation see Mark Levine's "The Jazz Theory Book"

[Tal_175]

Sheryl Bailey calls it the family of four in the case of dominants. So for G7 you get: Bmin7b5, Dmin7 and FMaj7. These are combined with the G bebop scale (the fourth in the family) to create arpeggio up - scale down type of bebop licks.

For major chords, you'd usually have primary and secondary minors. So for CMaj7, you'd have Emin7 and Amin7 (also maybe G major triad).

The general rule is any substitution that gives you a musical extension is in the family. Emin7 = CMaj9, Amin7 = C6 etc.

[dconeill]

...
My memory is failing me for a group name for these chords; I suppose you could call them chords from the harmonized major scale; perhaps someone else has a better name. ...

For a complete explanation see Mark Levine's "The Jazz Theory Book"

Well, that neuron finally fired. "Diatonic chords in C Major" for the ones the OP listed originally.

[caminium]

Thanks all. “Family of Four” makes sense.

[Reg]

Yea, as started by Caminum.... Diatonic chords with a Relationship to a Scale. Simply ....chords constructed from each degree of a Scale, (any scale), and constructed in diatonic 3rd from the notes of the scale.

We as guitarist tend to then label scales constructed from each scale degree as a Mode of that Scale. Which results in a different Modal series of Diatonic chords from each scale degree... which is basically musical slang etc.. Who cares.

Usually this leads to "Diatonic Functional Relationships". Where the chords are musically organized using harmonic terms... Tonic, Sub Dominant and Dominant .... This is very important and useful as jazz musician.

So using your maj scale starting on C (Cmaj)

Cmaj7, E-7 and A-7 , or Imaj, IIImin7 and VImin7 are all Tonic (at rest)
D-7 and Fmaj7, or II-7 and IVma7 .......are Subdominant (slight tendency for movement to Tonic or Dom)
G7 and B-7b5, or V7 and VII-7b5..... are Dominant (the most tendency for movement to Tonic)
These are labeled... Diatonic Subs. You're probable are aware of Tritone subs or sub V's etc.

These Diatonic Functional Relationships are usually expanded with Jazz....to chords above and below a diatonic 3rd of the target chord.... Like The Tonic Chords above,
If Cmaj is the Target.... the chords above and below a diatonic 3rd are .... E-7 and A-7. Usually labeled "Diatonic Functional Subs". Somewhat the expanded versions of Ms Bailey's Family of Four.

Obviously if one just keeps using the same musical organization of Targets or References and then creates Relationships with that Reference....It becomes easy to see and hear many Chord Progressions and Chord Patterns and all the possible subs that expand those progressions... throw in a few more musical organizational relationships and you'll have it.... you'll be a jazz player.

It's just a few more Layers of musical organization to become aware of...

I know.... I've pushed all the BS many times. Who cares. It does show up in your playing, and can be easily heard.

[StringNavigator]

Is there a name for the relationship between the chords of a triad? For example; Cmaj7, Em7, G7. Or G7, Bmin7b5, Dm7. I call them 'cousin chords' but didn't know if there's actually a real name for it.

Tertiary Harmony forms Upper Structures.
A C E G B D F A CE G B D F A C E G B D F A.........
Knock yourself out!

[ragman1]

Chord families (harmonic functions) - Andy French's Musical Explorations