Diatonic Chords - Part II

Modifications & Extensions

Chord modifications and extensions have aleady been described in the lesson Intervals & Chord Construction. The following interactive blackboard shows the possible modifications and extensions for every diatonic chord of the major scale that you may create with scale tones*. Because of the position of half steps in the scale not all modifications/extensions are available or make sense on every scale degree: e.g. we have a b9 instead a 9 on the III. and VII. scale degree. Only on the IV. scale degree there is a #11 instead an 11. Wether a chord modification or extension sounds good also depends on whether the basic chord is a triad, 7th chord or 6th chord.

*) Alterations like b9, #9 or b13 for dominant 7th chords or the transformation of the III. degrees Em7 into E7 when resolving to the IV. degrees Am chord are changing the scale for that moment and therefore are not discussed in this lesson.

Explanatory Notes

Modifications and extensions on the interactive blackboard

Written in brackets
  • Works tonally, but you will normally interpret the chord based on a different root and write it as slash chord, e.g. F/C instead of C6sus4.
  • Just works in certain combinations, e.g. sus4 sounds great as modification of a triad, but as a modification of a maj7 chord it is very dissonant.
Crossed out in red
  • Generally very dissonant on this scale degree.
  • The nomenclature practically doesn't exist (e.g. addb9, susb2, sus#4)

Alternative interpretations of a chord

Reinterpretations of a chord often result in two variations, depending of the possibly omitted 5th of the original chord will be considered in the new interpretation. When writing a lead sheet you will normally prefer the simpler version that is easier to read, giving the player the freedom to extend the chord by himself.

I. scale degree

common, possible uncommon rather considered as: dissonant, impossible
Csus2 Cmaj7sus2 → G/C Cadd11 ("C4")
Csus4 C6sus2 → Gsus2/C, C6/9(no3) Cmaj7sus4
Cadd9 C6sus4 → F/C, F(add9)/C Cmaj7(11)
Cmaj7(9) [=Cmaj9] C6(11) → Fmaj7/C, Fmaj7(9)/C  
Cmaj7(13) [=Cmaj13]  
C6  
C6(9) [=C6/9]  
Csus4add9 [=Csus2/4]  

Annotations

Csus2, Csus4 The 3rd is replaced by the major 2nd (sus2) or by the perfect 4th (sus4). You can play both instead of a plain C major chord.
Cadd9 Major chord (triad) plus major 2nd (=9th), but without a 7th (here the major seventh maj7). Commonly used in pop music instead of a plain major chord.
Cmaj7(9) This one is very frequently used for a plain maj7 chord in jazz and latin music.
Cmaj7sus2 Tonally possible, but normally interpreted/written as slash chord G/C instead of Cmaj7sus2. One of the quite often used slash chords.
Cmaj7(13) 6th and major 7th together mean a lot of color and charming tension: recommended for jazz oriented music (especially ballads), should rather be used sparingly.
C6 The major 6th extends the C major chord instead a major 7th.
C6(9) [=C6/9] Great as the final chord of a song instead a plain C major or Cmaj7.
C6sus2 Also possible, you might reinterpret this chord as Gsus2/C. However, you'll not find this chord very often. In practice you will most likely hear or play this chord when a C6(9) respectively C6/9 (identical chord, alternative notation) is written and the 3rd has just been omitted on the guitar.
The 4th/11th can cause heavy dissonances
Cadd11 The perfect 4th is quite dissonant in combination with a major 3rd and thus normally just occurs as sus4, replacing the 3rd. But there are some voicings (mostly played with open strings) on the guitar that are not uncommon and sound good when played in an arpeggiated way to create kind of a melody that goes back and fourth from the 4th to the major 3rd. Sometimes such a chord is slightly incorrect named C4 instead of Cadd11. Instead of add11 you may sometimes find add4 in the chord name.
Cmaj7sus4 Very dissonant. The 4th is fighting with the major 7th.
Cmaj7(11) Also painful.
The 6th moderates the dissonance caused by the 4th

Actually most extended 6th chords are just inversions or slash-chords of common chords:

C6sus4 Instead of C6sus4 you can see this chord as a simple F/C slash chord (respectively Fadd9/C, if the tone G - the 5th of C [=9 of F] - is considered as indispensable).
C6(11) Acting on the assumption that you won't find a string or finger to play this chord with the tone G - the 5th of C anyway, the chord matches a pure Fmaj7/C. With the G it's a Fmaj7(9)/C [=Fmaj9/C].

II. scale degree

common, possible uncommon rather considered as: dissonant, impossible
Dsus2, Dsus4 D7sus2 → Am/D  
Dm(add9), Dm(add11) D6sus2 → Asus2/D  
D7sus4 D6sus4 → G/D, G(add9)/D  
Dm7(9) [=Dm9] Dm6(11) → G7/D, G7(9)/D [=G9/D]
Dm7(11) [=Dm11]  
Dm7(13) [=Dm13]  
Dm6  
Dm6(9) [=Dm6/9]  
Dsus4add9 (Dsus2/4)  

Annotations

Dsus2, Dsus4 The minor 3rd is replaced by the major 2nd (sus2) respectively by the perfect 4th (sus4). You can play both instead of a plain Dm chord.
Dm(add9) Possible, but not very common, because you'll rarely feel the necessity to omit the 7th. Thus you may normally write a Dm7(9) [=Dm9]. You can often hear a Dm(add9), because in a Dm9 bar chord you have to abandon the 7th to add the 9th to the chord. In comparison to major chords the harmonic function or tension doesn't change so much by playing the chord with or without its minor 7th.
Dm(add11) Possible, but like the Dm(add9) chord you can sometimes see the Dm(add11) as a Dm7(11) [=Dm11] chord that is played without the 7th (and there will rarely be a good reason to avoid the 7th).
D7sus2 Possible, but rather written as Am/D instead.
D7sus4 Possible, but since in minor chords the minor 3rd can be played together with the perfect 4th, you may consider to write/play a Dm7(11) [=Dm11] chord.
Dm7(9) [=Dm9] Very common chord.
Dm7(11) [=Dm11] Also quite common.
Dm6 Instead of a minor 7th a major 6th is added to the Dm chord. You may notice the feel and tendency to resolve of a G7 chord. In fact, you can get a Dm6 when you play a G7(9) [=G9] with its 5th D in the bass instead of the root G. Therefore it feels like a G7(9)/D [=G9/D] even without containing a G. Anyway, you'll keep the chords name Dm6.
Dm6(9) [=Dm6/9] Analog to the Dm6 the Dm6(9) feels like a G7(13)/D without containing the root G, but no need to reinterpret the chord. You'll name this chord Dm6(9) or Dm6/9.
Dm6(11) Now this feels and really is a true G7/D, because the G remains in the chord despite the D in the bass. Should in most cases be written G7/D respectively G7(9)/D (just if you definitely don't want to give up the 5th A of the original Dm6(11) chord).
Dm7(13) A little bit special and loaded with tension. Like in the chords before the tritone interval between the minor 3rd (F) and the major 6th (B) makes it feel like the dominant chord G7. The Dm7(13) has a strong tendency to resolve to an Am7 or even better an Am7(9) chord (VI. scale degree = I. degree of parallel minor).
D6sus2 Possible, but certainly rare. Can also be interpreted as a Asus2/D. If this chord comes on the II. scale degree, you may consider to play/write an ordinary Dm6(9) [=Dm/9] chord.
D6sus4 Possible, but rather written as G/D respectively Gadd9/D, which occurs quite often.

III. scale degree

common, possible uncommon rather considered as: dissonant, impossible
Esus4 E7susb2 → Bdim/E, E7(b9,no 3) Esusb2
E7sus4 Em(b6) → Cmaj7/E Em(addb9)
Em(add11) Em7(b13) → Cmaj7(9)/E [=Cmaj9/E] Em7(b9)
Em7(11) Esus4(b6) → Am(add9)/E  
  Em(b6,11) → Am7(9)/E  

Annotations

Just a few modifications/extensions on the III. scale degree don't cause problems
Esus4, E7sus4 Both are possible.
Em(add11) Possible, but the Em(add11) can often be seen as an Em7(11) [=Em11] that is played without the 7th (there will rarely be a good reason to avoid the 7th)..
Em7(11) [=Em11] Possible and quite common.
The b2/b9 is troublesome
Em(addb9) Minor 3rd and b9 together: only for masochists! Actually you won't find the term "addb9" as rarely as "susb2".
Em7(b9) The minor 7th can't make minor 3rd and b9 shake hands: still dissonant.
Esusb2 Without the minor 3rd it doesn't get better: a plain susb2 chord would be to dissonant and therefore doesn't actually exist.
E7susb2 Coming along with the minor 7th, the susb2 chord is tonally possible, but will not be written that way. Instead you will interpret this chord as Bdim/E. You may also recognize this chord as an E7(b9) (III7 = dominant of the parallel minor key A minor) that is played wthout the 3rd - analytically written E7(b9,omit 3) respectively E7(b9,no 3).
b6/b13 mostly leads to reinterpretation when it comes with a minor chord
Em(b6) Tonally possible. A minor 6th is played instead of a minor 7th (the 6th on the III. scale degree is a minor 6th), but usually chords with a b6 are reinterpreted. This chord will rather be seen as Cmaj7/E.
Em7(b13) Tonally possible, but more likely written as C(add9)/E or, if the tone B - the 5th of Em7(b13) - is not left out, as Cmaj7(9)/E [=Cmaj9/E].
Esus4(b6) Tonally possible, but more likely written as Am/E respectively Am(add9)/E (depending on whether the tone B - the 5th of E - is played along or left out).
Em(b6,11) Tonally possible, but should rather be written as Am7/E or, with the 5th of E, as Am7(9)/E [=Am9/E].
Wild: b2/b9 and b6/b13 together
Em(b6,b9) The minor 6th can't calm the fight between minor 3rd and b9. You could also name this chord Cmaj7(11)/E, but for Cmaj7(11) we already detected a strong dissonance (see annotations of the I. scale degree).
Esusb2(b6) This one sounds disgusting as well. Reinterpretation doesn't help.

IV. scale degree

common, possible uncommon rather considered as: dissonant, impossible
Fsus2 Fmaj7sus2 → C/F Fsus#4
Fadd9 F6sus2 → Csus2/F, F6/9(no 3)  
Fmaj7(9) Fsus#4 → F(#11,no3) bzw. F(#11,omit3)  
Fmaj7(13) F6sus#4 → F6(#11,no3) bzw. F6(#11,omit3)
F6  
F6/9  

Annotations

Fsus2 and Fadd9 With or without the major 3rd: both variations are popular instead of a plain major chord, especially in pop music.
Fmaj7(9) Very frequently used for a plain maj7 chord, especially in jazz and latin music.
(Fsus4) Doesn't exist because of the augmented 4th an the IV. scale degree.
Fmaj7sus2 This chord is quite popular as C/F and should always be written that way.
F6 Very common. No reinterpretation required, but the alternative interpretation as Dm/F or Dm7/F is also common.
F6(9) [=F6/9] Possible, but rarely applicable on the IV. scale degree because of the chords prefered function as resolutionchord respectively final chord of a song.
F6sus2 Also possible, you might reinterpret this chord as Csus2/F. Can also be heard sometimes when a F6(9) respectively F6/9 (identical chord, alternative notation) is written and the 3rd has just been omitted on the guitar.
Fmaj7(13) 6th and major 7th together mean a lot of color and charming tension: recommended for jazz oriented music (especially ballads), should rather be used sparingly.
The augmented 4th
Fmaj7(#11) Also known as the "lydian chord". Very popular especially in jazz music, particularly in ballads. Sometimes the maj7(#11) chord is even used as a resolution chord on the I.scale degree (IIm7 V7alt Imaj7#11), causing an interesting change of the scale (I ionian → I lydian).
sus#4, add#11 The terms sus#4 and add#11 are actually inexistent in practice, although both types of chords can be attractive. However, those chords are (like many others in this lection) just working in a certain sequence of intervalls (voicing), where the 5th and the #4/#11 don't form a b9 (actually the 5th can just be omitted): F, C, F and B works fine, while F, B, F, C is very dissonant because of the b9 between B und C. Sometimes such a chord is perceived, when the #11 occurs as a strong (longer sounding) melody tone. In this case you may even abandon the #11 in the chord symbol.
Fsus#4 To avoid writing sus#4, you might notate a chord withe the tones F, C, F and B as F(#11,no3) respectively F(#11,omit3). Or just write sus#4, actually why not?
Fadd#11 Also here: why not? But you may also see this chord as an Fmaj7(#11), where the maj7 was just omitted. You should just test whether adding a maj7 would sound good and go with the style of the music. If not, just don't hesitate to write Fadd#11 or F(#11) or F(#11,no maj7).
F6sus#4 Quite dissonant, but eventually attractive when played in an arpeggiated way. In this case just write F6sus#4 or F6(#11,no3) respectively F6(#11,omit3), because reinterpretation would probably make it even more complicated.

V. scale degree

common, possible uncommon rather considered as: dissonant, impossible
Gsus2, Gsus4 G7sus2 → Dm/G Gadd11 ("G4")
Gadd9 G6sus2 → Dsus2/G, G6/9(no3) G7(11)
G7sus4 G6sus4 → C/G, C(add9)/G G6(11)
G7(9) [=G9]    
G7(13) [=G13]  
G6  
G6(9) [=G6/9]  
Gsus4add9 [=Gsus2/4]  

Annotations

Gsus2, Gsus4 The 3rd is replaced by the major 2nd (sus2) or by the perfect 4th (sus4). You can play both instead of a plain G major chord.
Gadd9 Major chord (triad) plus major 2nd (=9th), but without a 7th. Very common especially in pop music instead of a plain major chord.
G7sus2 Possible, but rather written as Dm/G instead.
G7sus4 Very popular chord. Very often G7sus4 G7 is played instead of Dm7 G7. You may also split a bars of G7 into G7sus4 and G7.
G7(9) Very popular, especially in jazz, funk and related music.
G7(13) Also a common variation of the G7 chord, especially in jazz, funk and related music.
G6 The chord is equipped with a major 6th instead of a 7th. This reduces the tendency to resolve to a chord on the I. scale degree, which e.g. works great in the chord progression e Am7 | G6 | Fmaj7.
G6(9) [=G6/9] Works fine on its own, but because of its prefered application as a resolution chord (final chord of a song), you will hardly ever stumble across a 6/9 chord on the V. scale degree.
G6sus2 Also possible, you might reinterpret this chord as Dsus2/G. Can also be heard sometimes when a C6(9) respectively C6/9 (identical chord, alternative notation) is written and the 3rd has just been omitted on the guitar.
G6sus4 Instead of G6sus4 you can see this chord as a simple C/G slash chord (respectively Cadd9/G, if the tone D - the 5th of G [=9 of C] - is considered as indispensable).
G6(11) Acting on the assumption that you won't find a string or finger to play this chord with the tone D - the 5th of G anyway, the chord matches a pure Cmaj7/G. With the tone D it's a Cmaj7(9)/G [=Cmaj9/G].
As chord extension the perfect 4th is causing a dissonance with the major 3rd:
Gadd11 The perfect 4th is quite dissonant in combination with a major 3rd and thus normally just occurs as sus4, replacing the 3rd. But there are some voicings (mostly played with open strings) on the guitar that are not uncommon and sound good when played in an arpeggiated way to create kind of a melody that goes back and fourth from the 4th to the major 3rd. Sometimes such a chord is slightly incorrect named G4 instead of Gadd11. Instead of add11 you may sometimes find add4 in the chord name.
G7(11) Very dissonant, but in some cases applicable when played appegiated (11 and 3rd seem to form a melody then instead of being hit simultaneously)

VI. scale degree

common, possible uncommon rather considered as: dissonant, impossible
Asus2, Asus4 A7sus2 → Em/A  
Am(add9), Am(add11) Am(b6) → Fmaj7/A  
A7sus4 Am(b6,9) → Fmaj7(#11)/A  
Am7(9) [=Am9] Asus2(b6) → Fmaj7(#11)/A  
Am7(11) [=Am11] Am(b6,11) → Dm7/A, Dm7(9)/A [=Dm9/A]
Asus4add9 [=Asus2/4] Asus4(b6) → Dm(add9)/A
  Am7(b13) → F(add9)/A, Fmaj7(9)/A [=Fmaj9/A], Csus4/A

Annotations

Asus2, Asus4 The minor 3rd is replaced by the major 2nd (sus2) respectively by the perfect 4th (sus4). You can play both instead of a plain Am chord.
Am(add9) Possible, but add9 comes more often with major chords, because you'll rarely feel the necessity to omit the 7th in minor chords. Thus you may normally write a Am7(9) [=Am9]. You can often hear a Am(add9), because in a Am9 bar chord on the guitar you have to abandon the 7th to add the 9th to the chord. In comparison to major chords the harmonic function or tension doesn't change so much by playing the chord with or without its minor 7th.
Am(add11) Possible, but like in the Am(add9) chord you will rarely feel the need to omit the 7th and thus consider to prefer to write/play an Am7(11) [=Am11] chord.
A7sus2 Possible, but rather written as Em/A instead.
A7sus4 Possible, but since in minor chords the minor 3rd can be played together with the perfect 4th, you may consider to write/play a Am7(11) [=Am11] chord.
Am7(9) [=Am9] Very common chord.
Am7(11) [=Am11] Also quite common.
Chords with b6/b13 should usually be reinterpreted
Am(b6) Tonally possible. A minor 6th is played instead of a minor 7th This chord will rather be seen as Fmaj7/A.
Am(b6,9) Sound more like an Fmaj7(#11)/A (even if you skip the maj7 E = 5th of A). You will hear this particularly if you want to resolve a II-V-I progression to m(b6,9), e.g Bm7b5 E7alt. Am(b6,9). It simply doesn't work. Am6/9 would give you the feeling of resolution to a tonic chord, but this causes a change in the scale from A aeolian to A dorian or melodic minor.
Asus2(b6) See Am(b6,9). The missing minor 3rd of A6sus2 (the tone C) equates the 5th of Fmaj7(#11). Therefore the interpretation as Fmaj7(#11)/A doesn't change - with or without the 5th of F.
Am(b6,11) Tonally possible, but should rather be written as Dm7/A or, with the 5th of A, as Dm7(9)/A [=Dm9/A].
Asus4(b6) Tonally possible, but more likely written as Dm/A respectively Dm(add9)/A (depending on whether the tone E - the 5th of A - is played along or left out).
Am7(b13) Tonally possible, but more likely written as F(add9)/A or, if the tone E - the 5th of Am7(b13) - is not left out, as Fmaj7(9)/A [=Fmaj9/A].

VII. scale degree

common, possible uncommon rather considered as: dissonant, impossible
Bdim(add11) Bdim(b6) → G7/B Bsusb2(b5)
Bm7(b5,11) Bsus4(b5,b6) → G7(13,no5)/B B7susb2(b5) [=F/B]
Bm7(b5,b13) Bm(b5,b6,11) → G7(13)/B Bdim(addb9)
Bsus4(b5)   Bm7(b5,b9)
B7sus4(b5)   Bdim(b6,b9)
    Bsusb2(b5,b6)

Annotations

Just a few chord modifications don't cause problems on the VII. scale degree.
Bdim(add11) Tonally possible, but it's even simpler to play on the guitar with the minor 7th included = Bm7(b5,11). It will rarely make sense prefer a Bdim(add11) over a Bm7(b5,11).
Bm7(b5,11) Possible and trouble-free.
Bm7(b5,b13) The b13 is also possible as tension tone here.
Bsus4(b5) Possible, when used with the right voicing: 1 b5 1 4 is possible, 1 4 1 b5 sounds awful. Better add the minor 7th:
B7sus4(b5) Possible. If you're not resolving to a plain Bm7(b5) before you go further, you may prefer a Bm7(b5,11), which contains the minor 3rd and the (perfect) 4th.
Like on the III. scale degree, the b2/b9 is troublesome
Bdim(addb9) Minor 3rd and b9, that already was hardly tolerable on the III. scale degree. With the b5 here it's even getting worse. Neither the term "addb9" nor "susb2" are existing in practice.
Bsusb2(b5) Also without the 3rd a susb2 chord is very dissonant and practically inexistent. The b5 does the rest.
B7susb2(b5) A reinterpretation as F/B might look more elegant and corresponds better to what you hear, but doesn't make the chor less dissonant.
Bm7(b5,b9) Added to the half-diminished chord Bm7(b5) the b9 doesn't sound as dissonant as added to a plain minor 7th chord, but still far away from sounding harmonic.
b6/b13
Bdim(b6) Tonally possible - but definitely recognized and better written as G7/B, which is quite common.
Bsus4(b5,b6) Tonally possible, can alternatively be written as G7(13,no5)/B respectively G7(13)/B.
Bm(b5,b6,11) Tonally possible - but definitely recognized and better written asG7(13)/B.
b2/b9 and b6/b13 together
Bdim(b6,b9) While it was possibe to reinterpret Bdim(b6) as G7/B, a reintrpretation of Bdim(b6,b9) would reult in a G7(11)/B and G7(11) was already doomed as to dissonant.
Bsusb2(b5,b6) Matches the previous Bdim(b6,b9), but without the minor 3rd. Can also be seen as a G7(11)/B, just without the 5th of the G7(11). Hence, it's to dissonant as well.

Tip: While the Oolimo Guitar Chord Finder shows chord shapes for the most common chord types, you can enter your own guitar chord shapes into the Chord Analyzer and find the most appropriate chord name/interpretation for the most extraordinary guitar chords...