Variations using Tone.Sequence

Using some of the editing functions available in Tone.Sequence and Tone.Part you can make changes to selected sections of a pre-defined Sequence or Part. We use it on this page to create a walking bassline for a 12 bar blue progression. Then using the Editing functions we make changes as the bassline loops through multiple choruses of the 12 bar sequence. The specific technique used here is combining six 2 bar phrases for each 12 bar blues chorus. Each of the 2 bar sections is created by randomly choosing a pattern from a set of typical bassline patterns. Since there are 10 different patterns for each of the six sections, there are many dozens of possible combinations.

key: tempo: | | volume: |

Melodic patterns can be represented as scale degrees from a starting reference or root. The numbers 1 2 3 4 5 6 7 8 represent a major scale. Chromatic alteration of b's and #'s are added as needed. For example a Dorian scale is represented as 1 2 b3 4 5 6 b7 8. Below are the 2 bar patterns that are used during bars 1-10. The computer is randomly choosing one for the first five times. Bars 11-12 commonly known as the 'turnaround' use different patterns that are also shown below. (the comma ',' means one octave lower)

Basic Bassline patterns

  1.    1 3 5 6 8 6 5 3
  2.    1 3 5 6 b7 6 5 3
  3.    8 b7 6 b6 5 4 b3 3
  4.    1 8 b7 5 1 5 4 3
  5.    1 3 4 #4 5 4 b3 2
  6.    1 2 1 ,7 1 2 b3 3
  7.    ,5 ,6 ,b7 ,7 1 2 b3 3
  8.    1 1 1 ,b7 ,5 ,5 ,6 ,5
  9.    1 1 2 2 b3 b3 3 3
  10.    1 ,5 1 2 b3 3 1 2
        

Turnaround patterns

  1.    1 b7 6 b6 5 4 b3 2
  2.    1 b7 6 b6 5 b3 2 b2
  3.    1 3 4 #4 5 6 b7 7
  4.    1 b7 6 b3 2 b6 5 b2
  5.    1 #5 6 #1 2 #4 5 ,7
  6.    1 3 4 1 4 #4 5 b2
  7.    1 3 4 1 2 #4 5 ,5
  8.    1 1 4 4 1 1 5 5
  9.    1 1 3 3 4 #4 5 ,5
  10.    1 3 b7 6 b6 #4 5 ,5

Lilypond notation file

When you press the stop button (if you've let it play for more than four choruses) the first four choruses of the bassline (48 measures) are saved in a lilypond file format. Lilypond is open source music notation software. The file created here can be pasted into lilypond. Next this file is saved and compiled into a postscript file which then is translated into a pdf file for viewing the standard notation of 48 measures of the bassline.

Lily Pond file