HARMONY

[rizlaman]

Can any1 help- i`m trying to understand harmony in music and i`ve been set an exercise(a personal interest & gain).
Firstly it reads play one octave of the scale of C, left hand the first tetrachord, right hand the second, keeping all the notes down. then play the scale of G repeating the top tetrachord of C with the left hand, and adding another the same shape with the right. Continue through the keys until you get back to C- What does this all mean? Can someone tell me how you go about this exercise on the piano-so i can practice,it`s probably really simple to you-please explain-many thanks!

[jdskee]

Firstly it reads play one octave of the scale of C, left hand the first tetrachord, right hand the second, keeping all the notes down. then play the scale of G repeating the top tetrachord of C with the left hand, and adding another the same shape with the right. Continue through the keys until you get back to C- What does this all mean?

Sounds to me like they are trying to show you how all the sharp major scales are related. Going "up" the keyboard, the "top" tetrachord for each scale will be the starting point of the "bottom" (or root) tetrachord for the next.  Its also showing you how the circle of 5ths works and that as you go up 5ths in scales you add sharps. When you go down 5ths (eg C to F) you add flats, so F would have 1 flat, Bb 2, etc. Note also that if you continue up as in their exercise, technically you wont end up back at C, but at B#. On the piano C and B# are the same.

[rizlaman]

Sounds interesting but can you explain how to tackle the exercise. Firstly what is a tetrachord? After how do you play a tetrachord using which notes? e.g can you like say
With the left hand Play note C & G (tetrachord) With the right hand play C up to C. Move up with tetrachords-you got the drift?
I know this is all wrong but Basically show me how to tackle the exercise and i would be very grateful. :-/
with regards
rizlaman

[jdskee]

Definitions -

Tetrachord: A group of 4 (hence 'tetra') notes, the first two separated by a step, the 2nd and 3rd by a step, and the 3rd and 4th by a half step.

Major Scale: a group of 2 consecutive tetrachords separated by a step.

Play the first four notes of the C major scale. Note that C to D is a step, D to E is also a step, and E to F is a step. Now notice that F to G is a step (the joining step). So the second tetrachord starts on G. G to A is a step, A to B is a step, and B to C is a half step.

This works for ANY major scale starting on any key, as long as you follow
     S-S-HS          -S-                S-S-HS
Tetrachord1   Joining Step  Tetrachord2

Try the exercise, you will see what I mean.

[rizlaman]

What i did in the excercise after your feedback is;

1. Held down C-F with the Left hand
2. Played C-F in the right hand
3. Held G-C in Right hand
4. Played G-C in Left hand
Two tetrachords were done.
Onto G
1. Held down G-C in left hand
2.Played G-C in Right hand
3. Held D-E-Fsahrp-G in Right hand
4.Played D-G in Left hand
Now the 2nd tetrachord was the root of D
ONto A then E then B then F finally C
Does this sound right?

[jdskee]

Everything looks good except this last part, you should be ending up on F# from B not F, so you are skipping the keys of F#, C#, G#, D#, A#, E#, and finally B# (which is the enharmonic of C). F is a flat key and does not exist when you move up 5ths in keys from C, however it does exist enharmonically on a piano keyboard as E#.

Just so you know, when you do this exersise properly I think you will be have to transpose down a few octaves when you get to the G# or A# scale, since you will run out of keys.