Viviuos said:
How are the far eastern (original scales) and European scales different, and why is there a difference?
Here is why there is a difference. It may even be correct/interesting.
Here is an overtone series for A-55Hz.
This is based on the fact that the overtones of a musical note (those which produce the tone of the note) are integer multiples of the fundimental frequency. Which I took as an axiom earlier.
Since a doubling of frequencies represents an octave of a note, we need to consider only the odd interger multiples.
Overtone 1 - 55Hz
Overtone 3 - 165Hz
Overtone 5 - 275Hz
Overtone 7 - 385Hz
Overtone 9 - 495Hz
Overtone 11 - 605Hz
Overtone 13 - 715Hz
Overtone 15 - 825Hz
Overtone 17 - 935Hz
Now, to give you some idea of the relative volume levels of these overtones, you can play them at the following neck positions:
Overtone 3 - harmonic over the 7th fret of the A string (divides the string in 1/3 - 2/3).
Overtone 5 - harmonic over the 4th fret of the A string
(dividing the string in 1/5 - 4/5)
Overtone 7 - harmonic over the 10th fret of the A string?
(dividing the string in 3/7 - 4/7)
The other harmonics are available at the same integer ratios as their overtone numbers. That is overtone-9 will be heard when you divide a string in n/9 and strike the harmonic there.
I don't have my tape measure with me so, that's basically how to find them.
Using this method you can really see that the power of these harmonics drops off really quickly as you get higher and you need to strike harder to produce an audible tone.
Now, dividing these harmonics so that we are playing in the same range as our even-tempered scale we see the following:
Overtone 1 - 55Hz
Overtone 3 - 82.5
Overtone 5 - 68.75
Overtone 7 - 96.25
Overtone 9 - 61.875
Overtone 11 - 75.625
Overtone 13 - 89.375
Overtone 15 - 103.125
So striking a single note produces the following overtones (and higher).
A - 55Hz
E - 82.5 (a little sharp compared to even-temperment)
C# - 68.75 (a little sharp)
G - 96.25 (a little flat)
Bb - 61.875 (a little flat)
Something about 1/2 way between D and Eb - 75.625
Something about 1/2 way between F and F# - 89.375
G#- 103.125 (a little sharp)
Tuning system basically try and reconcile the three tendancies.
1. 5th are the second most audible note in the overtone series.
2. There should be an integer number of notes in an octave.
3. When striking a note, an overtone series is produced, chords sound pleasant when they do not deviate far from this overtone series.
These are somehow related to "the key" of a piece.
That's the why is there a difference. I'll let someone who has more information on the currently existant scales answer how they differ.