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The Harmonic Series As Universal Scientific Constant
Modern education emphasizes the harmonic series as establishing the natural
foundation of quantification (numbered partials function as divisors of monochord string
length), and so it is presented first as a common reference. Everything that follows
concerns its colorful mythologizing in narrative allegory. Pitch notation now implies
equal temperament tuning, 100 logarithmic cents per semitone, and so deviations are
shown here in cents, for only the reference pitch (1200 cents to the octave) is accurately
notated. The 7th partial--which plays a strange “oversight” role in ancient mythology-suffers most from this misrepresentation (it is perceptibly flat and is not adequately
notated), but the 5th and 10th are somewhat less so. If the plucked string of a monochord
(and a guitar serves conveniently) is touched very lightly at these fractional lengths then
all other partials will be silenced; thus the string will prove that its fundamental tone is
actually a composite that human ears accept as a unity. (Energy falls off rapidly in the
higher partials, so the first few are easiest to isolate.) We are partners in the objects of our
attention.
cents
C
C
G
C
e
G
b
1
2
3
4
5
6
7
1200
702
498
octave
fifth
fourth
386
316
major 3rd
minor 3rd
267
[oversight]
C
D
8
231
e
9
204
10
182
(alternate wholetones)
This deified Pythagorean “Ten-ness” inherited from the Marduk/Baal mythology
of ancient Mesopotamia stops right here in identifying tuning ratios for two very good
reasons, easily inferred, and beautifully illustrated by Ptolemy in the second century AD.
1) Once the music starts we normally cannot distinguish between wholetones of 8:9 and
slightly smaller ones of 9:10, so that Ptolemy’s example of a tetrachord (four consecutive
tones) progressing 9:10, then 10:11, and finally 11:12 clearly spans a musical fourth of
3:4=9:12 and in a way that can beguile melodically, but it makes nonsense out of any
discrimination between wholetones and semitones. But there is an even worse problem,
2) for the augmented fourth at 7:10 cannot be distinguished from the diminished fifth at
5:7, at least without reference to a third pitch, so that we can no longer even count
sensibly. (Musicians habitually refer to both as “tritones,” further confounding this issue.)
Thus trouble lies ahead no matter how carefully we begin with perfect consonances
accurately defined and labelled. This apparent “flaw” in Creation arises only because we
love both perfect octaves and perfect fifths, fourths, and thirds, so that our surfeit of
perfections conflicts with cyclic Necessity (deified by Plato in the 2:1 octave) “with
whom not even the gods can contend.” We are stuck with somewhat incompatible desires,
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a rather general condition of being human. In modern theory these partial numbers are
ratios of frequency, reciprocals of string lengths.
What we hear as a “musical” tone turns out to be, on physical analysis, a
“manifold” of partials with varying proportions of the total energy, so that hearing is
always influenced by invisible and normally inaudible forces, a “magic” beyond our
control except as, in performance, we become the magicians. Thus sound functions as the
greatest clue to psychic “interiority” without ever fully disclosing its secrets.
A piano tuned in equal temperament (with 12 equal semitones to the octave)
offers a convenient mapping of pitch classes through more than seven octaves. The
niceties suggested by cents values are ignored for 87 consecutive semitones that preserve
the illusion that octaves, fifths, and fourths are reasonably well-tuned, and we try to
ignore what happens to thirds and sixths. (Players of all fretted instruments fret endlessly
over the intrusion of mistuned thirds in particular.) The pattern of black and white digitals
on a keyboard is a constant reminder that semitones occur at B:C and E:F after either two
or three consecutive wholetones. The eye immediately locates two possible centers of
symmetry in any twelve-tone “octave”—either on the white key “D” framed by a black
pair or on the middle black key in any set of three and named either G-sharp or A-flat.
“G /A
” as alternate center of symmetry.
“D” as cultural center of symmetry.
A persistent belief in the ancient Near East that the cosmos is a perfect inverse
symmetry that unfolded originally from the middle makes it convenient to locate “Deity”
on pitch class “D” and to “map” all tones on the local clock with D at the modern “zero
hour” of 12:00 o’clock. The immediate result is to locate G /A
directly opposite at
6:o’clock on a “moral” plumb line pointing to the square root of 2 that
divides
D
the octave proportionally into equal halves that we identify tonally
as a
tritone (meaning three wholetones). And dividing each tritone in the
same way (now by the “fourth root of 2”) locates our equaltempered B and F on the horizontal “balance beam” dividing
the cyclic octave into four equal tempered minor thirds (rising D:F,
F:A , as opposed to falling D:B and B:G ).
It is an historical coincidence that our meticulous care in defining
tuning
systems happens to correspond visually (meaning geometrically) with a more casual
description of the ancients that already spoke of the “octave” 2:1 as if it divided equally
into twelve semitones like the hours of the day and of the night although they also
understood perfectly well that their own correlations were only approximate. Plumbline
and balance beam were idealized notions borrowed from carpentry and commerce, and
their 12-tone octaves were as variable as lunar months, but they drew circles and divided
F
S
S
F
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them equally long before they learned to make tone numbers approach that geometrical
accuracy proportionally, for “music” in a general sense became understood as ratio
theory. The most important single idea seems to have emerged in Mesopotamia with
eventual discovery that the difference between the longest day and the shortest night in
the latitude of Babylon approximates the difference of a wholetone between a musical
fourth and a musical fifth. This assumption links music to the calendar as a cycle of
twelve—quite indifferent to each other but not to us, and so tonal cosmology emerges
from the mists of history as an almost natural human convenience. It is a cultural
consequence of our effort to make sense of things, whatever the cost. Discovery that the
musical fifth emerges as two-thirds of the reference string length (true also on blown
pipes under certain conditions to be explained in an essay on pitchpipes) eventually
produces the Sumerian deity ENKI (Babylonian EA) as “god 40” (meaning two-thirds of
sixty)—the only member of the pantheon wise enough to anticipate the future, and god of
the arts and crafts. As a linear time measure we can locate two-thirds of 60 as 40 minutes
on the local clock, but as a proportional measure of pitch in the 2:1 musical octave twothirds correlates with 7 hours in a cycle of 12, and this contrast between two kinds of
equality proves endlessly fascinating. From this initial insight we can map the 12
normative tones in a “tone-circle” with as much accuracy as we please. If the first
musical fifth of ratio 2:3 embraces seven semitones (or three wholetones and a semitone
as Philolaus affirms in the 5th c. BC) and lies at 7:00 o’clock, then all subsequent fifths
can be located at 7-hour intervals and enjoy Mesopotamian mantles of radiance, a
beautiful metaphor from Enuma Elish, the Babylonian creation epic dating to the time of
Hammurabi (c. 1800 BC). The locus of F C G D A E B and their relatives can be
understood without doing any arithmetic. Our oldest tuning texts (for the 9-string
Akkadian lyre) date to this period and cover the entire set of thirteen pitch classes in the
spiral of fifths, shown here in modern alphabetical notation.
A
E
B
F C G D A E B F
C
G
We attune ourselves to the cultural foundations of civilization by thinking of
creation as proceding symmetrically from the middle by the first ratio (2:3) that creates
new pitch classes, mapping this spiral in opposite directions at intervals of seven hours on
a local clock. These basic concepts employed in my studies of ancient musical allegory
are designed to pry us lose from contemporary habits without losing the advantages of
modern precision. But glance at the cents values in the harmonic series and notice that the
musical fifth is given a “rounded” value of 702 logarithmic cents. After 12 such intervals
we accumulate a cyclic excess of 24 cents. Or if we tune fourths of 3:4 worth only 498
cents we are deficient by the same amount. But every tone is surrounded by a Platonic
“no man’s land” within which the ear cannot make decisions. And that human disability,
which varies widely among us, opens the door to alternative systems. It is a both a
blessing and a curse--one of the most powerful metaphors in the Bible. Here lies both sin
and salvation.
S
S
S
F
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2:3
A
wwwharmonic series.doc © 2003 Ernest G. McClain
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Now look back at Figure 1 and notice that two musical thirds of 5:6 + 6:7
compose a musical fifth of 316+267 = 583 logarithmic cents in modern values. Then add
together the cents values of the three wholetones defined by 7:8 + 8:9 + 9:10 that
compose a logical fourth of 7:10 as a tritone of 231+204+182 = 617 cents, now 34 cents
larger than the tritone fifth of 5:7 worth only 583 cents. Our system degenerates into
verbal nonsense inviting maximum misunderstanding. And what is the practical result?
The logical ambiguity right here has turned out to be one of the richest resources
in musical harmony. Because the ear and mind can be surprised and confused composers
possess a kind of fulcrum on which to pry us loose from one perspective while a new one
dawns on consciousness. A defect from one point of view is a blessing in disguise from
another, and in this case it becomes an active ingredient in modern harmony.
But how did the ancients regard this complexity in “Pythagorean” theory? We
happen to inherit two remarkable kinds of evidence. Historically first, the Akkadian lyre
tunings of Kilmer, Crocker and Brown, dating to c.1800-1600 BC, seize on this
ambiguous tritone fourth/fifth as the defining element in their version of our seven “white
key” diatonic modes, for in each modal octave this interval occurs between different pairs
of numbered strings. So this earliest image of the tonal cosmos is ultimately defined by
ear (and the god Marduk/Baal is born with “four enormous ears”). The world out there is
understood by analogy with an inner experience.
A strictly logical Greek description by Aristotle is a second valuable heritage. He
points out that the ear cannot distinguish between a “third-tone” and a “quarter-tone” as
defined in fourth century BC Greece (Archytas ratios of 27:28 and 35:36 are excellent
approximations). And in the standard wholetone of 8:9 worth 204 cents a twelfth part is
17 cents, exactly half of the 34 cent contradiction we are finding here. Aristotle’s figure
estimates the general human limits of excess and deficiency in aurally confirming
anything. From his figures we can deduce that among 12 such pitch classes in an octave
of six wholetones nearly half of the potential “tone-space” consists of a Platonic “no
man’s land” surrounding each tone. Modern temperament now equalizes tritone fourths
and fifths but their ambiguity remains, and Aristotle’s estimate of aural tolerances
remains valid.
In this sea of possibilities within an octave 2:1 digitalized in various ways I
welcome Alfred North Whitehead’s advice: “The guiding motto in the life of every
natural philosopher should be, Seek simplicity and distrust it” (Concept of Nature, Ch. 7).
It is a personal credo pervading all of these essays.