Step bass improvisation exercise on the piano

Usually step bass on music is going down. Like a cat going down stairs step by step.


Examples are countless. Vocalise - Rachmaninov, Air - Bach, Whiter Shade of Pale - Procol Harum, Seven Seconds Away - Youssou N'Dur, Neneh Cherry...


Why?


Is it because symmetry requires that hands move in mirror [Bach]? Is it because the melody has a tendency to go up?





Here is a step bass which can be played on the piano by the left hand. Then a melody can be made up or improvised by the right hand.


It is written in the key of C major, so all keys are white.


The rhythm is on the bass. And if it is the first time you play on the piano with both hands, the bass has to be learned first. Then while still concentrating on the bass pattern and rhythm, the right hand can be added. The right hand may initially play random notes. That is ok. This is how improvisation begins...or even continues...


So here is a little exercise:


The bass goes slowly. We have 4 (equal in time) beats per bar or written line in this post.


Counting...
1234
123and
C23C
B23B
A23A
G23G
F23F
E23E
D23D
G23G
C (going back to begining)


If chords are added at a later stage they can use the rule of preparing the human brain for what is to come. This is possibly the same to avoiding consecutive fifths, for example CEG, BDF which sounds very bad in music.


So bass C can be harmonized as C E G
Then bass B can be harmonized as B D G (note G is borrowed from the previous chord)
To summarize, it may sound bad changing all notes from one chord to the next. See also the principle of least change in music. (The less change the more sophisticated and refined the result. For example the harmonization of Vocalise by Rachmaninov).


Here is one way it can be harmonized:


Bass C as GCE (this is CEG but rearranged)
Bass B as GBE (note this chord borrows G, B from previous one)
Bass A as ACE (standard 135)
Bass G as GBE (136, or in figured bass notation G6)
Bass F as ACE (1357, or in figured bass notation F7)
Bass E as GBE (135 ie EGB but rearranged)
Bass D as FACE (E prepared from previous chord, so D9)
Bass G as GCD resolved to GBD (G45 to G)


Reference:


Bach Bass Rules:


https://normanschmidt.net/scores/bachjs-general_bass_rules.pdf


The Joy is in Playing - Snoopy