Knowing that basic chord structure seems a mystery to most, I thought I’d post about it, though just in basic form.
Often when I post music I’ve written, or a famous song that I’ve arranged I get people asking about chords.
Here are the basics
All examples will assume the key of C.
C Major is C E G in its first inversion (2nd inversion is E G B, and 3rd is G C E)
To make that chord minor, you just flatten the third, so C Eb G (where ‘Eb’ means E flat)
To make diminished, you flatten both the third and fifth, so C Eb Gb.
To make the chord augmented, you sharpen the fifth C E G#.
a C7 always implies a dominant 7th, C E G Bb****
Cm7 would be the same, but with E being flattened.
a CMaj7 is C E G B
Another tricky one is Csus (C suspended) which usually means to include the perfect fourth, and sometimes the major second, so you’d play the C chord, including the F. Problem is, The F is next to both the third, and the fifth, so it can make it sound odd.
That’s really all there is to it. Those are the chords that most pieces require you to know.
Also, and less important, each of the notes of the scale have specific names
tonic (often incorrectly called the root). Root is for the chord, tonic for the scale.
subtonic (or leading)
These are all relative to the key that you’re in. So in the key of C, C is the tonic, D is the supertonic and so on.
Some of the names should be obvious. The ‘super’ and ‘sub’ are one above and one below.
Tonic means first note in the scale.
Mediant is a third above the tonic (and middle note of the major triad in first inversion)
submediant is a third below the tonic (and middle note of the major triad in second inversion)
Dominant (creates the dominant chord)