First things first, only certain frets will give you harmonics. But when you lightly touch above the fret-nub on the special frets, you'll get a bell chimey "touch harmonic".
But there are different types of touch harmonics, the harmonic-potent frets can be organised into groups based of the tone of their harmonic. I will label for you the harmonic tones on a guitar in standard tuning
x=no harmonic...on fret
%=produces unknown/unclear tone
1 2 3 4 5 6 7 8 9 10 11 12 <----Fret #'s
e|-x-|-x-|-x-|G#-|-E-|-x-|-B-|-x-|G#-|-x-|-x-|-E-|
B|-x-|-x-|-x-|D#-|-B-|-x-|F#-|-x-|D#-|-x-|-x-|-B-|
G|-x-|-x-|-x-|-B-|-G-|-x-|-D-|-x-|-B-|-x-|-x-|-G-|
D|-x-|-%-|-%-|F#-|-D-|-x-|-A-|-x-|F#-|-x-|-x-|-D-|
A|-x-|-%-|-%-|C#-|-A-|-x-|-E-|-x-|C#-|-x-|-x-|-A-|
E|-x-|-%-|-%-|G#-|-E-|-x-|-B-|-x-|G#-|-x-|-x-|-E-|
13 14 15 16 17 18 19
e|-x-|-x-|-x-|G#-|-x-|-x-|-B-|
B|-x-|-x-|-x-|D#-|-x-|-x-|F#-|
G|-x-|-x-|-x-|-B-|-%-|-x-|-D-|
D|-x-|-%-|-%-|F#-|-%-|-x-|-A-|
A|-x-|-%-|-%-|C#-|-%-|-x-|-E-|
E|-x-|-%-|-%-|G#-|-%-|-x-|-B-|
So,
4th, 9th, & 16th row harmonics all sound identical on a single string, they produce whatever tone that the 4th fret of that string would normally make.
7th & 19th Row harmonics all sound identical on a single string, they produce whatever tone that the 7th fret of that string would normally make.
5th row harmonics they produce whatever tone that string is tuned to
12th row harmonics they produce a tone 1 octave higher than the 5th row harmonic of that string.
-Hope this helps
Nicholas Jacquet
