The Sucharitra Coscale

A while ago I posted about some chords from the Sucharitra scale and then I mentioned them again in connection with using the coscale idea. This post expands a bit on what I've been doing with this approach.

The Sucharitra scale is spelled 1 #2 3 #4 5 b6 bb7. If 1 is C, we have C D# E F# G G# A (I'll use sharp spellings and avoid double flats in this post when I can). Looked at another way, here it is as a subset of the 12 available notes in standard temperament:

Chromatic: C C# D D# E F F# G G# A A# B
Sucharitra: C D# E F# G G# A

If you like, you can see any collection of notes as being "carved out" of the chromatic by removing some notes. In a sense the "negative space" of the missing notes defines the scale just as well as the "positive space" of the notes that are included.

There are five notes that are not in Sucharitra. For a few years now I've been referring to them as its "coscale".

Chromatic: C C# D D# E F F# G G# A A# B
Sucharitra: C D# E F# G G# A
Sucharitra Coscale: C# D F A# B

Of course they don't form a scale in my normal sense because they don't have a root note, but you can define any one you like or just treat the coscale as a collection of notes that's available to you when playing Sucharitra.

Here's how that could be visualised on the fretboard. The top fretboard shows C Sucharitra, with the roots in a darker shade. The next is the same but with all the other notes coloured orange. Next we remove all the notes from C Sucharitra, but leaving the roots in for reference (this step is unnecessaary but you might find it helps you "see" what's going on). Finally we erase the roots and arrive at C Sucharitra Coscale:

With a bit of squiting you can see the coscale as a dominant 7 arpeggio with added b9 and #9. Here I've make the "root" of this arpeggio darker and the b9 and #9 extensions lighter to help bring out the pattern:

Note that the "root" of the arpeggio is a whole step below the actual root -- i.e. this is Bb7b9#9 played over a C root. Conceptually, at least; it could be that your harmony has no root note and this point and this is more a way of thinking than something that's in the music itself.

To go with the sequence of Sucharitra chords I posted here, here are some coscale chords. Try using them as extra colours in a Sucharitra progression, or indeed as a sequence with its own internal logic [EDIT: There's a typo in the heading, the root should say C not A; I can't now be bothered to recreate the diagrams again just to fix that!]:

To me these chords are sharp and sour; they make quite a strong contrast with Sucharitra itself.

Finally, let's look at the coscale in terms of overlapping transpositions. For this part let's treat treat Sucharitra Coscale as a 7b9#9 arpeggio, i.e. I'll spell it 1 b2 b3 3 b7. So we'll forget about it being a coscale of anything and just treat it as a pentatonic scale in itself. When thinking in scale terms it's sometimes useful to respell this as 1 b2 b3 b4 b7 instead.

Here's what I got from a quick Python script (the first number is semitones to shift up, in brackets are how many of the resulting notes are also in the original Sucharitra coscale, asterisked rows are modes):

      3 : b2 b3 3 b5 5    ( 3)
      9 : 1 b2 5 6 b7    ( 3)  *

      1 : b2 2 3 4 7    ( 2)
      2 : 1 2 b3 4 b5    ( 2)  *
      6 : 3 b5 5 6 b7    ( 2)
      10 : b2 2 b6 b7 7    ( 2)
      11 : 1 2 b3 6 7    ( 2)  *

      4 : 2 3 4 5 b6    ( 1)
      5 : b3 4 b5 b6 6    ( 1)
      7 : 4 5 b6 b7 7    ( 1)
      8 : 1 b5 b6 6 7    ( 1)  *

It looks as if shifting the coscale up or down by a minor third stays closest to the original, although with only 3 out of 5 notes shared it's not all that close. Combining either of these with the original coscale produces a 7-note scale:

     1 Sucharitra Coscale:   1 b2 b3 b4        b7
    b3 Sucharitra Coscale:     b2 b3 b4 b5 5
     6 Sucharitra Coscale:   1 b2          5 6 b7
     1 + b3              :   1 b2 b3 b4 b5 5   b7 
     1 + 6               :   1 b2 b3 b4    5 6 b7 

Combining the coscales at the 1 and b3 gives Super Locrian bb6, which is a mode of Melodic Minor b5. Of course, combining 1 and 6 gives a mode of this scale. So perhaps we can think of Sucharitra Coscale as "belonging to" Melodic Minor b5 in some way. I don't know much about this scale; maybe I should. We could think of it as "stealing" two notes from Sucharitra to make a 7-note scale, with the remaining 5 notes of Sucharitra acting as its coscale; a kind of distorted mirror image of where we started.

The 1-note overlaps are much closer to Sucharitra itself. Of these I guess the last one is the most natural to look at, since it's a mode of the Sucharitra coscale and is easy enough to find -- just shift the whole pattern down a fret.

The 2-overlap ones can be seen as mergings or blends of Sucharitra and its coscale.I draw your attention to this:

    b2 Sucharitra Coscale:     b2 2 3 4       7
    b7 Sucharitra Coscale:     b2 2     b6 b7 7
    b2 + b7:                   b2 2 3 4 b6 b7 7

Playing these two together produces a new 7-note scale and, yes, it's a hypermode of Melodic Minor b5. The same trick works with the other two: 2 Sucharitra Coscale plus 7 Sucharitra Coscale produces another Melodic Minor b5 hypermode. The 1-overlap transpositions have the same structure: two pairs that combine to produce two hypermodes of Melodic Minor b5 (one of which happens to be an actual mode).

I appreciate this probably looks a bit pointless at this stage but these structures can be musically very useful as they provide a lot of distinctive, repeatable material out of which you can build meaningful and understandable musical relationships. I don't want to put too many different things on my plate right now but Melodic Minor b5 is definitely going on my list of things to explore further.

These relationships could form the basis of an expanded harmonic language for Sucharitra that could span a whole composition. But they can also just be things to explore in search of a quick lick or melodic idea that gets translated into a more traditional framework.