Round about this time, having dealt with (or, at least, mentioned) major and minor chords, 6th chords and 7th chords, it would be wise to consider two more permutations:

DIMINISHED AND AUGMENTED CHORDS

A diminished chord starts off much the same as a minor chord, but goes mad halfway up. C minor is:

whereas C diminished (written 'C dim' or sometimes 'C°') looks like this:

It is the diminished fifth interval within the chord that gives it its name. If you examine the diminished chord carefully, you'll see that it's made up of three equal intervals; C to E♭, E♭ to G♭ and G♭ to A, all minor thirds. A fifth note added to these four would be a C octave

, and the interval between that and the A below it is again a minor 3rd.

This has an interesting implication; as diminished chords are always made up of successions of minor third intervals, the same four notes will serve to make up four different chords. In other words

is C dim;

is E♭ dim, but the same four notes are in use. Similarly, G♭ dim is

and A dim is

although the notes are positioned differently on the stave, C, E♭, G♭ and A are common to all four chords and the chords are thus essentially the same. A further implication is that there are, therefore, only three different types of diminished chord.

The first contains the notes C, E♭, G♭ and A and is C dim, E♭ dim, G♭ dim or A dim.

The second contains the notes C#, E, G, and B♭ and is C# dim, E dim, G dim or B♭ dim.

The third contains the notes D, F, A♭ and B and is D dim, F dim, A♭ dim or B dim.

The musical effect of a diminished chord (characterised by a feeling of mild suspense) is such that whatever the voicing, the chord sounds very similar; this is because the intervals acting within the chord are equal. Any diminished chord is thus interchangeable between four keys.

One finds that the augmented chord is subject to the same sort of mad logic. To arrive at an augmented chord, we take an ordinary major chord

and sharpen or 'augment' the fifth.

The interval between C and G# is known as an 'augmented 5th' (as the less dull-witted of you will recall) and this interval gives the augmented chord its name.

Like the diminished chord, the augmented chord is made up of equal intervals — in this case, the interval is a major third. C and E, E and G#, and G# and C are all major thirds, so the same three notes can serve as three different chords. C augmented (usually abbreviated to 'C aug') is

E aug is:

and G# aug is:

Different voicings, same three notes. There are then only four possible types of augmented chord.

The first contains the notes C, E and G#, and is C aug, E aug or G# aug.

The second contains the notes D♭, F, and A, and is D♭ aug, F aug or A aug.

The third contains the notes D, F# and A#, and is D aug, F# aug or A# aug.

And the fourth contains the notes E♭, G, and B, and is E♭ aug, G aug or B aug.

(One great advantage of this of course is that, unlike other chords, you needn't learn diminished and augmented chords in all twelve keys!)

Note at this point that there are no minor or major variations of diminished and augmented chords. In a way they are in a class of their own; whereas a sixth chord might be either a major sixth or a minor sixth, a diminished chord is simply diminished! You could in fact regard the diminished chord (consisting as it does entirely of minor 3rd intervals) as a special sort of minor chord, and by the same reasoning an augmented chord could be seen as a kind of major chord, as it's all made up of major 3rds.

Please remember that it is the third of a chord which determines whether the chord is minor or major.

If you're in any doubt about this, count the semitones between the root and the third; a minor 3rd is three semitones up from the root, whereas the major third is four semitones up. (For guitarists — a minor third is three frets up from the root, the major third is four frets up.) Better still try to get used to the difference in sound; of the two, the major has a brighter ring to it:

while the minor sounds a bit sad:

On chord charts, major chords such as C major, G# major and B♭ major will usually be abbreviated to plain C, G#, and B♭, and minor chords are written Cm, G#m, and B♭m (etc).

We're now going to take a quick sidelong glance at:

9TH CHORDS

To some of you denimed buffoons, the words 'ninth chord' may evoke agonising guitar shapes like

playable only after plastic surgery and sounding suspiciously like (dare I say it) jazz. May I suggest that you rough oiks amuse yourselves by defacing the rest of this article with your crucifixes, while the more refined of us sip our rare liqueurs and, settling comfortably back into our sumptuous red leather armchairs, discuss the 'noble ninth' with great solemnity.

Having constructed a chord as far up as the seventh, the next logical extra note to add is the ninth, that is the note an octave and a tone above the root of the chord

This chord

is C dominant 7, written C7, and this is C7ff9:

The interval between

(the root) and

is a major ninth, and any C chord containing a D note will be called some sort of ninth. 'Minor ninth' chords are arrived at by adding the ninth to a minor or minor seventh chord:

Here are a few different voicings of minor ninth chords which might appeal to you:

(Notice that in the latter three of these the ninth has been brought down an octave to sit in with the rest of the chord. Although the note is then technically a 'second' rather than a ninth, the chord is still a ninth chord!)

It is by no means obligatory to use the seventh in conjunction with the ninth.

is an example where the seventh has been omitted altogether from the chord — the chord name is then correctly a C9 rather than a C7/9. These voicings

of ninth chords also omit the seventh, and still sound good...

I fear there is much else to say on the subject of chords which I shall have to hold in store for next month. I realise I'm covering a lot of ground rather quickly, so don't hesitate to write to me at SI with any problems, corrections or insults which you might have. We're an understanding bunch here, and we realise you're by no means perfect, even if we are... Have a nice day! Yours with great humility and sincerity, DS.