Three-note root position chords have 2 versions:
1) Closed position
2) Open position
The largest interval between each of the three upper voices in closed position chords is a fourth. Anything more than that (up to an octave) makes it an open position chord. The distance between the tenor and bass could be up to one and a half octaves. Each of these two positions can have 3 different versions depending which note of the chord is in the top (soprano) voice.
1) If the root is in the soprano, then the C major chord would look like this (starting from the bass): C-E-G-C.
2) If the third is in the soprano - C-G-C-E.
3) If the fifth is in the soprano - C-C-E-G.
1) If the root is in the soprano - C-G-E-C.
2) If the third is in the soprano - C-C-G-E.
3) If the fifth is in the soprano - C-E-C-G.
EXERCISE: practice writing and later playing the tonic chord of each major and minor key in these 6 positions one after the other. When this becomes easy, try your hand with the subdominant (6 positions) and the dominant chords (6 positions). Finally, play all 18 chords one after the other without interruption (the last chord could be resolved to the tonic). When playing the bass part on the organ with pedals, take the tenor with the left hand and the upper two parts with the right hand.
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