Music & Geometry – Rhythm & Groove

Reading Time: 3 minutes

MUSIC & GEOMETRY – PART 3 – RHYTHM

GEOMETRY OF RHYTHM

So far in this article we have looked at the geometric relationships between tone (pitch) and geometric shapes (polygons and polygrams). Music though is more then tones alone. An important aspect of music is rhythm and just as with tones, polygons can be used to visualize rhythm.

How does this work?

Well a circle could be divided in any kind of time signatures. You could divide a circle into 4 (standard ‘4/4 time’) or into 3 (‘3/4 time’ – Waltz), into 5 (or ‘5/4 time’ – best known from Dave Brubeck’s “Take Five“), into 7 (‘7/8 time’ – Balkan rhythm), or what ever division you wish to use. 

Above you see a division of a circle into 32 parts (4-8-16-32). This can be used for ‘4/4 time’ musical pieces. 

You could draw various standard geometric shapes like for example squarestriangleslineshexagonshexagrams, et cetera.

That though will “limit” the rhythmic options you have. Small adjustments in standard shapes could turn a “static” groove into something more irregular or a groove that swings or shuffles …

STANDARD ‘4/4 TIME’ MEASURE – EXAMPLE 1:

In this example on the left you see 3 geometric shapes:1 5-sided uneven polygon, 1 dodecagon and 1 line.

The blue uneven 5-sided polygon visualized the kick drum, the yellow dodecagon visualizes the closed hi-hat and the red line visualizes the snare on the 2 and 4.

STANDARD ‘4/4 TIME’ MEASURE – EXAMPLE 2:

In the example on the left you see 4 geometric shapes:1 line, 1 blue square, 1 green square and 1 polygon with 12 uneven sides.

The blue square visualizes the kick drum in a so called “Four on the Floor” pattern (common for Disco and House music), the green square visualizes the open hi-hat, the yellow uneven-sided polygon visualized the closed hi-hat and the red line visualizes the snare on the 2 and 4.

These were just two very simple examples, but you could make these patterns as complicated as you wish.


XRONOMORPH

The absolute coolest free software you can use for turning geometric shapes into rhythm is called “XronoMorph”.

“XronoMorph is a free OS X and Windows app for creating multilayered rhythmic and melodic loops (hockets). Each rhythmic layer is visualized as a polygon inscribed in a circle, and each polygon can be constructed according to two different mathematical principles: perfect balance and well-formedness (aka MOS). These principles generalize polyrhythms, additive, and Euclidean rhythms. Furthermore, rhythms can be smoothly morphed between, and irrational rhythms with no regular pulse can also be easily constructed.

Each polygon can play an independent sound, and XronoMorph comes with a useful selection of samples to play the rhythms. Alternatively, you can load your own VST or AU plugins, or send MIDI to an external software or hardware synth. The rhythmic loops can be saved as presets within XronoMorph; they can also be saved as Scala scale tuning files, which means XronoMorph can be used as a tool for designing well-formed (MOS) and perfectly balanced microtonal scales.”

Watch the following videos to get a better idea about what you can do with this amazing software:

You can download XronoMorph for free from: www.dynamictonality.com


intervals superimposed

Intervals &
Scales

chord superimposed

Chords & Progressions

Rhythm &
Grooves

Tone-Merkaba above-below connecting-vertexes-across

Various &
Related


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Music & Geometry – Various & Related

Reading Time: 7 minutes

MUSIC & GEOMETRY – PART 4 – VARIOUS

In this part about music and geometry I like to share various related things.


“COUNTING CORNERS”

Another way to look at geometry and sound is angles (arc minutes) and the tones you could generate with them if you change the unit from degrees to Hertz:

The sum of the angles of these polygons could create the tone of F♯ at 180Hz, 360Hz, 720Hz and 1800Hz.

Other polygons – not found in the standard tone circles – would also create interesting tones. For example, the Pentagram (5 angles of 108°) would generate a C♯ a harmonic 5th at above 180Hz, a Septagon (7 angles of 128 4/7°) would generate an A♯ at 900Hz, the Octagon (8 angles of 135°) generating a C♯ at 1080Hz, et cetera …

With other words, the “series” of Polygons with increasing number of angles relates closely to the Harmonic Series in music.

Of course Hertz and Degrees is not the same thing. Most sound frequencies are ‘directional’ and/or ‘omni-directional’. No ‘sharp edges’ as with a triangle or square, but spherical and/or cone-shaped.

You can’t just “swap” units and say it’s all the same. But there does seem to be a lot of similarities between the math behind the units, as between many things in the universe. Some ‘laws’ seem to apply for a lot of things if not everything.


PLATONIC SOLIDS

We can’t call this geometry article “complete” without mentioning the Platonic Solids.

The reason to mention these is because of their obvious relation with a few of the shapes found earlier in this article, in particular the Trigon (triangle) and Quadragon (Square). 

The Platonic Solid that is a direct “one-on-one” match with musical geometry is the Tetrahedron. You can create a Tetrahedron by connecting 4 Trigons (the Major Thirds / Minor Sixths relationships within one octave within the tone circle).

For the Octahedron you would need 2 2/3 octaves, and 5 octaves for the Icosahedron.

The 3 Squares that represent the Minor Thirds and Major Sixths relationship within the tone circle only forms half a Hexahedron. You would need to cover 2 octaves to generate 6 Squares to complete the Hexahedron.

The only Platonic Solid that does not relate to the polygons created within the standard tone circle is the Dodecahedron, only in the Coltrane circle we could draw a Pentagon (and Pentagram).

Also interesting are the Schäfli Symbols {corners of the polygon shape of a face, edges connected to the corners}. Their recursive definition (or inductive definition) look similar to several tone interval ratios:

Tetrahedron

{3, 3}

3:3 = 1:1

UNISON

Hexahedron

{4, 3}

4:3

PERFECT 4TH

Octahedron

{3, 4}

3:4 (3:2·2)

PERFECT 5TH

Icosahedron

{3, 5}

3:5 (2·3:5)

JUST MINOR THIRD

For the Pythagoreans and later Greek philosophers, tetrachords were considered to be the auditory geometry of a “perfect” 4-sided, 4-pointed tetrahedron solid. As a geometrical model for music, the two tetrachords in a Greek mode could have been intended to represent two opposing and interlocking tetrahedrons balanced around a shared center, thereby creating the 8 vertices of a cube or hexahedron. Alternatively, the vertices (or points) of this cube could have also been intended to pinpoint the center of 8 triangular faces that form its geometric opposite, the octahedron. 

In either case, the geometric perfection represented by two balanced tetrachords is the founding principle behind the Greek modes and thus even our present major and minor system of scales.

Greek geometers found that tetrahedrons could be used to construct more complex perfect shapes. For example, a pair of octahedrons can be balanced to form either the 12 vertices of an icosahedron or 12 pentagonal faces of a dodecahedron. Because of this, tetrachords, octaves and a stack of twelve perfect 5ths were associated with the geometrical shapes of the five perfect solids, which the Greeks considered integral to the structure of the universe.

From: “Interference – A grand scientific Musical Theory” by Rich Merrick (www.interferencetheory.com)


For creating a 12-Tone Tetrahedron you need to combine 4 (2D) Trigons

1 Trigon is formed by the (3) tones of an Augmented Triad (C-E-Ab, Eb-G-B, Gb-Bb-D and Db-F-A). 

Each trigon shifts a semitone up or down at the corners with the neighboring trigons.


8-TONE (MAJOR SCALE) MERKABA

Merkaba is a combination of three different words. Mer is a light that rotates within itself; Kameant refers to the human spirit and Ba alludes to the physical human form (body).

A Merkaba is a star tetrahedron, a three dimensional 8 pointed star made from 2 tetrahedrons, one pointing up and the other down.

The Merkaba harmonizes male and female energy, much like a Yin/Yang symbol and is a representational invocation of “as above, so below”. The pyramid pointing upwards connects us to heavenly universal energy and represents yang, positive energy flows. The pyramid pointing downward connects to the earth and resonates with yin, negative energy flows.

The first “Tone Merkaba” I came across was the drawing below by Druvalo Melchizedek from his book “The Ancient Secret of the Flower of Life”. In his Tone-Merkaba Druvalo Melchizedek places the tones at the vertexes of the Merkaba based on the Major scale, connecting 2 groups of 4 tones (tetrachord) with 8 vertexes.

He starts at the female tetrahedron (point down) with Do (1) – whole tone to – Re (2) – whole tone to – Mi (3) – half tone to – Fa (4), scale degrees 1-2-3-4. At Fa he “crosses over” (with one whole tone) diagonally from one Tetrahedron to the other, the male tetrahedron (point up) and continues there with the same pattern of whole, whole, half tone: Sol (5) – whole tone to – La (6) – whole tone to – Si (7) – half tone to – Do (8), scale degrees 5-6-7-8.

In his concept the semitone leads to the vertex that changes the “polarity” (female to male and visa versa) when diagonally “crossing over”: Fa (4) to Sol (5) and Do (8) to Do (1).

Even though a very interesting concept, I wondered if there would be a different way to align the tones with the Merkaba. The “As Above, So Below” aspect of the Merkaba is not very clear with the way Melchizedek aligned the tones.

AS ABOVE, SO BELOW

If you haven’t read the Roel’s World article “The Functions of the Intervals” then that might be helpful to read first.

If we draw a line through the center located of the Merkaba, then 4 tones are located below the middle and 4 above (image left below).

Interesting is that when drawing lines from the vertexes through the center of the Merkaba, the opposing vertexes are each others inversions if you look at the scale degrees: 18 (Tonic & Octave), 27, (Seconds and Sevens), 36 (Thirds and Sixes) and 45. (Fourths and Fifths). And in all cases the degree of the connected vertexes combined generates the number 9 (number of completion).

Another interesting thing about this way of aligning the tones as displayed above, is that both horizontal planes of the tetrahedrons “rotate” in opposite direction 2→3→4 (clockwise) and 5→6→7 (counterclockwise).

If you would look at it from the point of the “Do’s” in 2D perspective, then the male “Do” (8) is grouped with 3 surrounding female tones: Re (2) – Mi (3) – Fa (4) and the female “Do” (1) is grouped with 3 surrounding male tones: Sol (5) – La (6) – Si (7).

This reminded me a little of the Yin-Yang symbol, where a dot of the opposite gender is located in the center of each half.

HUMAN VOCAL RANGE

There is yet another way to associate the 8 tones of the Major scale with the 8 vertexes of the Merkaba, this relationship is based on the human vocal ranges. The human vocal range is divided into 6 ranges, 3 female ranges, 3 male ranges, based on the everage vocal range of respectively women and men. From high (female) to low (male) these ranges are:

Female – Soprano: C4 – C6
Female – Mezz. Sopr: A3 – A5
Female – Cont. Alto: F3 – E5

Female: C-A-F (ascending 6ths / descending 3rds)
or inverted F-A-C (ascending 3rds)

Male – Tenor: B2 – A4
Male – Baritone: G2 – F4
Male – Bass: E2 – E4

Male: B-G-E (ascending 6ths / descending 3rds)
or inverted E-G-B (ascending 3rds).

To turn these 3-tone chords into 2 4-tone chords we have to add one tone to each group.

The Female group does have a C / Do (1) already, so the second Do (8 – Octave) has to be added to the Male groupD-F-A-C (a Dmin7 chord), scale degrees: 2-4-6-8 (even numbers).

The only tone of the C Major Scale that is missing, is the tone D / Re (2). When we add this tone to the Female group we get the following group (chord): C-E-G-B (a CMaj7 chord), scale degrees: 1-3-5-7 (uneven numbers).


What version of the Tone-Merkaba you should use (Druvalo Melchizedek’s Tone-Merkaba, the “As Above, So Below” Tone-Merkaba or the Tone-Merkaba based on the human vocal range) is up to you.


TONES, ASTROLOGY & GEOMETRY

If you know a little about astrology, then you must have recognized some of the geometric shapes used in the tone circles earlier in this article, in particular those of the intervals. The tone circles might have also reminded you of the way the Zodiac Circle is draw. 

Note: The Zodiac Signs in this article are placed clockwise and with Aries “on top”. Traditionally the Zodiac Signs are drawn counterclockwise with Aries on the left. Another difference is that the “cusps” (the line in between the signs) traditionally align with North, South, East and West.

Both tone circles though are drawn as traditionally used, thus turning the Zodiac Circle to match both tone circles (music is the main subject of this article after all) seemed to be more convenient reading and comparing the tone circles with the Zodiac Circle.

astrology & geometry

The degrees listed above relate to the angles of 2 dots relatively to each other from the center point of the geometric shapes..

Read more about musicastrology and “Tone Zodiacs” in the article “Zodiac Signs & Tonality (Music)“.


intervals superimposed

Intervals &
Scales

chord superimposed

Chords & Progressions

Rhythm &
Grooves

Tone-Merkaba above-below connecting-vertexes-across

Various &
Related


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Music & Geometry – Harmony – Chord Progression

Reading Time: 12 minutes

MUSIC & GEOMETRY – PART 2 – HARMONY

Before we continue exploring geometric shapes of harmony first some additional information about tone circles and harmony … Tone Circles are a very important tool when it comes to harmonic progression (or chord progression) in music.

RELATIVE MAJOR / MINOR TONALITIES

You see here the Circle of ascending Fifths/Fourths with both Major and minor tonalities. The relationship between the Major and minor tonalities is of course the same in the Chromatic Circle.

Even though the relative Major and minor are on the same side of the circle they do not automatically “replace” each other musically.

For example:  the geometric relationship C Major and G♭ Major is the same as the geometric relationship between A minor and E♭ minor. The relationship between C Major and E♭ minor might look the same geometrically within the circle but is a different one! The tonic of C Major is a Tritone apart from G♭ Major, but only a minor 3rd apart from E♭ minor.

In these articles about music and geometry I have chosen to only us the circles with Major tonalities to have more space for drawing lines between the tones of the circle that form the geometric shapes (polygons and polygrams).


DIFFERENCES BETWEEN THE CHROMATIC CIRCLE AND THE CIRCLE OF FIFTHS:

You might have noticed that the tone circles above have different “shades of grey” for their tones. This is done for a reason. From a “philosophical” point of view you could say that – when you look at the “movement” around the circles – the Chromatic Circle represents ‘Polarity‘ and/or ‘Dualism‘ and the Circle of Fifths represents ‘Unity‘ and/or ‘Nondualism‘. 

Of course the Circle of Fifths can be read counterclockwise as well, but than it would not longer be the Circle of Fifths but the Circle of Fourths instead. In other words, the Chromatic Circle is bidirectional (same interval size in both directions) and the Circle of Fifths (clockwise) unidirectional, as is the Circle of Fourths (counterclockwise).

CHROMATIC CIRCLE

When we look at the Chromatic Circle, then we can see two “poles”C and F♯/G♭. From these “poles” we move around the circle in both directions. Now, imagine placing a “mirror” from C to F♯/G♭, then: 

B is “mirrored” by C♯ | D♭ → (5♯/7♭ | 7♯\5♭),
A♯ | B♭ is “mirrored” by D → (10♯/2♭ | 2♯\10♭),
A is “mirrored” by D♯ | E♭ → (3♯/9♭ | 9♯\3♭),
G is “mirrored” by F → (1♯/11♭ | 11♯\1♭),
G♯ | E♭ is “mirrored” by E → (8♯/4♭ | 4♯\8♭).
F♯ | G♭ “mirrors” itself within → (6♯ | 6♭),
as does C → (0♯ | 0♭).

The numbers of ‘accidentals’ stays the same but the “polarity” has changed (sharp to flat, positive to negative, “male” to “female”).

The two opposites of Yin and Yang (the image on the right, turned 90 degrees to align with the tone circle) attract and complement each other and, each side has at its core an element of the other (represented by the small dots). Neither pole is superior to the other and, a correct balance between the two poles must be reached in order to achieve harmony.

To me the Yin and Yang symbol (circle) represents Octave (complete scale), the Tritone interval (geometric mean) “splits” the octave in half: black half (Yin), white half (Yang). The dots represent the two most important intervals in music, the white dot = 5th (3:2, arithmetic mean – Yang, the sun) and the black dot = 4rd (4:3, harmonic mean – Yin, the moon). Both “lead” to the opposite half, across the “border” (the Tritone), the white dot to the white half (down, 5th to the Tonic) and the black dot to the black half (up, 4th to the Octave).

CIRCLE OF FIFTHS

When going around the Circle of Fifths the build-up and decrease of the number of sharp and flats is constant. The sharps going up 0-11 while the flats go down simultaneously 11-0. And another pattern to be seen: 0 – 1 – 2 – 3 – 4 – 5 – 6 – 5 – 4 – 3 – 2 – 1 (- 0). 

As you can go around this circle endlessly An natural gradualness with no beginning, no end. Ouroboros, (the tail-devouring snake). A unbroken circle, a cross-cultural symbol often representing completeness which encompasses all space and Time, “infinity” or “unity“.


GEOMETRY OF CHORDS

Just like with scales also chords form geometric shapes. For this article I will only share the shapes and Polygons for C Major and C Minor. These shapes are the same though for all 12 tonalities.

TRIGON (triangle)
The clockwise “connected” tones are a Major Third (400 cents) apart from one another: The triad formed by playing all 3 tones of the trigon together is called “Augmented Triad“. C-E-A♭ & A♭-C / G-B-E♭ / D-G♭-B♭ / D♭-F-A.  

SQUARE
All 4 tones (C-G♭-E♭-A / D-A♭-F-B / E-B♭-D♭-G ) together forms a “Diminished 7th Chord“, containing two simultaneous played TriTones a Minor Third apart.

Every first image bellow visualizes the Chromatic Circle (CC), every second the Circle of Fifths (CoF).

C MAJOR (CM)

C MINOR (Cm)

SUPERIMPOSED MIRRORED

12 TONALITIES

Other common chords in all 12 tonalities superimposed (the colored polygons are C chords). Every first image bellow visualizes the Chromatic Circle (CC), every second the Circle of Fifths (CoF).

C dim

C Aug

Cm7

C7

CM7

As you might have noticed, there are various chords that “generate” the same image when all 12 tonalities have been superimposed, no matter if you use the polygons of the Circle of Fifths or the Chromatic Circle.

There are of course many more chord variations with additional tones such as a 4, 6, 9, 11 and others.


HARMONIC PROGRESSIONS

When you draw a square around the Circle of Fifths and draw lines between the corners of the square, 4 triangles appear. In each triangle we see the chord progressions that belong to the Major tonality in the center of the outer ring, highlighted by the green triangle. Diminished chords are usually not drawn into the tone circle, but to complete the picture I have added it into a 3rd ring in the center. 

This concept only works with the Circle of Fifths. It does not work this way with the Chromatic Circle.

The example below is based on C Major, but you could turn the Circle of Fifths in any direction to see the chord progressions for any other Major tonality.

DEG.TONEFUNCTIONCHORD
1CTONICC MAJOR
2DSUPERTONICD MINOR
3EMEDIANTE MINOR
4FSUBDOMINANTF MAJOR
5GDOMINANTG MAJOR
6ASUBMEDIANTA MINOR
7BLEADING TONEB DIMINISHED

Two examples below of the ‘movement’ created by chord progressions:

BLUES PROGRESSION

A standard Blues uses the 1st, 4rd and 5th degrees:
I → IV → I → V → (IV) → I

See how the movement between the chords of a standard Blues takes place in the outer ring (chords with a Major 3rds).

Turnaround 3-6-2-5-1

TURNAROUND

Standard turnaround uses the 1st, 2nd, 3rd, 5th and 6th degrees:
III → VI → II → V → I

A turnaround creates a “z-like” patern, from the inner ring (minor 3rds) to the outer ring (Major 3rds).


THE “SEQUENCE OF FALLING FIFTHS”

The purple Septagram displayed earlier also visualizes another aspect in music as well: the “harmonic progression” or “chord progression“, a succession of musical chords. This chord progression is the foundation of harmony in the Western musical tradition.

The numeral sequence of the falling (descending) Fifths goes as follows:
(4 -) 7 – 3 – 6 – 2 – 5 – 1

Musicians and composers generally prefer using the Roman numerals instead though:
(IV -) VII – III – VI – II – V – I

In C Major we get the following chord sequence: 
(F Major -) B diminished – E minor – A minor – D minor  – G Major – C Major.

All “steps” in the sequence “lead” to the tonic, the root of the tonality a composition is written in. I’ve put the (IV) in the sequence above between brackets, because the interval between F and B is not a Fifth but a Tritone


“THE SEQUENCE OF FALLING FOURTHS”

Radans-Tone-Circle-by-Zachary-G-Covell

If you place the 4 on the other side of the reversed sequence then we get a perfect sequence of descending Fourths”: 4 – 1 – 5 – 2 – 6 – 3 – 7: 
F Major – C Major – G Major – D minor – A minor – E minor – B diminished.

This “Sequence of Falling Fourths” actually appears when you use the RADIAN measure of 57.29577951 degrees when going ’round the Circle of Fourths (or Circle of Fifths in clockwise movement), as Zachary G Covell demonstrates (see image on the right).

Zack writes: “After 7 times around the circle all four of the 90 degree lines are filled in. The 11th, 22nd, 33rd, and 44th step in the lines placing each one at a new radian of 57.29577951 degrees becomes the axes of the directions at 90 degrees to one another. Only a musician or someone who knows some music theory will see the 4152637 locations. The 4152637 are Harmonic Progression in Music.

Going around the Circle in 7 times isn’t a “coincidence” either. When stacking (slightly tempered) Fourths / Fifths you will rise 7 octaves before you come across the “same” tone as you started with (but 7 octaves higher) and “close” the circle. I talk about “tempered” Fourths / Fifths in this case, because if you stack Just (perfect) Fourths / Fifths you would slightly ‘overshoot’ the circle with approx. a quartertone (this difference between 12 stacked Perfect 5ths and 7 stacked Octaves is also called the “Pythagorean comma“) and would thus generate a spiral and not close the circle, as demonstrated by Zach.

The 11th, 22th and 44th are Tritones. The 33rd is not (it’s a “Quartertone“), nor are the 55th, 66th, and 77th. But the 88th is, as is the 176th … This is because there are some “doubling sequences” within the harmonic series as well. The most obvious is that of the 1st harmonic (fundamental): 1-2-4-8-16-32-64-et cetera. But, so does the “Tritone” in the harmonic series: 11-22-44-88-176-352-et cetera. The 33rd harmonic (a “Quartertone”) “doubles” as follows: 33-66-132-et cetera, as does the 55th harmonic: 55-110-220-et cetera … you see the “system of doubles” within the harmonic series, right?

For the “number fetishists” and philosophers among us:

The numerologists among you might have noticed the 11, 22, 33 and 44 series, the so called “Master Numbers” (although not all numerologists use 44).

These numbers are also the first 4 double digit palindromic numbers, numbers that remains the same when its digits are reversed. The Circle of Fifths can be used both ways, the interval stays the same only the direction changes, ascending (clockwise) vs. descending (counterclockwise) 5th.

In the Bible the numbers 11 and 22 symbolize disorder, chaos and judgment. The Tritone is commonly experienced as the most “dissonant” or “tensionful” in the 12-Tone system. 33 represents “God’s Judgement”.

If you count from the 1st line drawn in the circle, the 33rd Harmonic becomes the last “leg” of the cross and the beginning of the last “sequence” (of 4) to close the circle/cycle. 
In the Bible a 44 day period began on the day Jesus was crucified and ended with his resurrection. When you look at the circle, the 44th harmonic completes / ends the circle/cycle. It “ends” the “period” between “crucifixion” (33rd Harmonic) and 44th Harmonic.

I know these things don’t have much to do with math or geometry, but are fun nonetheless. *wink*


“AUTUMN LEAVES” PROGRESSION & THE GEOMETRY OF THE AUTUMN EQUINOX

When you “map” the chord progressions of some compositions using the Circle of Fifths, geometric shapes may appear as well. Robert Aguirre discovered a very interesting one, relating the Jazz standard “Autumn Leaves” with the Autumn Equinox:

Autumn Leaves & the Autumn Equinox

Since you went away the days grow long … And soon I’ll hear old winter’s song …


THE COLTRANE CIRCLE

An interesting variant to the “Circle of Fifths” is the “Coltrane Circle”, created by saxophonist John Coltrane (perhaps based on Nicolas Slominksy’s Thesaurus of scales and musical patterns?) and was used by Yusef Lateef for his work “Repository of Scales and Melodic Patterns“.

Being a saxophonist myself and a fan of Coltrane’s work I had no choice then to write something about this tone circle in this article as well.

Below on the left you see a scanned copy of an original drawing of the “Coltrane Circle”. I have modified an image made Corey Mwamba from his article “Coltrane’s Way Of Seeing” that clarifies the scanned image (right image).

A Pentagram & Pentagon appear when you draw lines between the same tones in the Coltrane Circle” (in this example with the tone C).

In the original drawing Coltrane had “circled”. specific tones. If you connect the circled tones a dodecagram is formed.

NOTE: There is a lot more that can be said about the Coltrane Circle as well as the geometric relationships between chords and chord progressions in some of his music, in particular the album Giant Steps. If you like to know more about this, then read this Roel’s World article: “The Coltrane Tone Circle.


POLAR HARMONY – CHANGING “POLARITY” (“NEGATIVE HARMONY”)

The following images are based on a concept shared by Ernest Levy (writer of “A Theory of Harmony“) where every chord has a “reflection”, a “polar opposite” chord within that key center, created by rotating every single tone around the axes of that key center. With other words, with this concept you can substitute a chord by changing it’s “polarity”. Some musicians refer to this method as “Negative Harmony”. The mirror “reflection” is representative of the reflective qualities between the harmonic and subharmonic series, (“otonality & utonality“).

In this concept the axes between the tonal center (root) and Fifth (the interval between the second and third harmonics, generally considered as the most important and consonant interval) is used to “mirror” chords and scales.

A simple way to visualize it is to “mirror” the chord in the Tone Circle. 

In the first image you see the polygon of G7 and the the tonic of C. In order to create the “mirror” in the Chromatic Circle (1st images) you need to draw a line between the tonics of the G7 and C chords and add perpendicular to this – C axis the “mirror” (image 2). In image 3 you see the mirrored polygram of G7, that turns out to be a F Minor 6 (as noted in the 4th image). The process is pretty much the same with the Circle of Fifths (2nd images), except that you add the “mirror” directly in between the tonic and fifth of the tone center.

G7

AXIS & MIRROR

MIRROR G7

Fm6 (AXIS)

Substituting G7 with Fm6 is changing the direction of approach to resolve at CG to C is a Descending FifthF to C an Ascending Fifth. The F Minor 6 chord could also be seen / notated as a D7b5 chord, but it will not “accentuate” the dominant function as traditionally with G7 or alternatively it’s “reflection” Fm6.

Famous musicians like saxophonist Steve Coleman (interesting read: Symmetrical Movement Concept) and Herbie Hancock have used “Negative Harmony” in their music. This subject gained most “exposure” and “popularity” recently due to Youtube videos by/with Jacob Collier.


TONNETZ GRID

Another way to visualize (and perhaps easier way to “map” the “polar conversion” of) a chord, is by using the Tonnetz Grid. In musical tuning and harmony, the Tonnetz Grid (German for tone-network) is a conceptual latticediagram representing tonal space first described by Leonhard Euler in 1739.

This way of visualizing “negative harmony” can be found in detail at this imgur post. For this Roel’s World article I will only show you the example as described above with G7 and C. I’ll use a Tonnetz Grid image by Jan Ott for it:

Polar or Negative Harmonics – Tonnetz Grid

As you might have noticed, the in the Tonnetz Grid “connected” tones on the horizontal lines are a 5th apart. The tones connected diagonally from left-top to right-bottom are a Minor 3rd apart, the tones connected diagonally from bottom-left to top-right are a Major 3rd apart. 


3 DIMENSIONAL REPRESENTATION

Some authors have taking mapping tone relationships one step further, turning the more “traditional” 2D Polygons into 3D shapes. At the website www.cosmometry.net for example Marshall Lefferts converted the 2D Circle of Fifths into a 3D Vector Equilibrium.


Marshall Lefferts writes: “This illustration shows that the tri-tone intervals are exactly opposite each other in the circle of fifths”. [left]
“In this way we can easily see the six pairs of opposite notes that comprise the basic 12-tone system of music.”

“Extending this into the 3-dimensional space of the vector equilibrium, one of the primary components of cosmometry, we can map these pairs like this (notice that the circle of fifths is maintained in the sequence of notes as they are arrayed visually around the center).” [image right]

Buckminster Fuller stated that the vector equilibrium is composed of six-pairs of equal and opposite vectors radiating from its center point. The music system aligns with that model conceptually, though of course the frequency differences of the actual tri-tone notes are not equal.”

Instead of blogging more about the 3 dimensional representations of musical harmony and tone-relationships it might be more useful to share some very interesting videos made by others with you:


NEO-RIEMANNIAN TONNETZ TORUS

An interesting variation of the Tonnetz Grid shown above, is the Torus (or Donut-) shaped Neo-Riemannian Tonnetz Torus.

The red lines connect notes that are a Major Third (and Minor Sixth) apart. The green lines connect notes that are a Minor Third (and Major Sixth) apart. The blue lines connect notes that are a Perfect Fifth / Perfect Fourth apart.

With those 3 lines (one of each color) triangles can be formed. These triangles represent either Major (red–green–blue / RGB) or Minor (green–red–blue) Triad (3-tone) Chords.


intervals superimposed

Intervals &
Scales

chord superimposed

Chords & Progressions

Rhythm &
Grooves

Tone-Merkaba above-below connecting-vertexes-across

Various &
Related


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