The Voyage of the Golah Iota (1993)

Some of the notes for my 1993 work, "The Voyage of the Golah Iota," are pertinent to "Colony" so I'll repeat them below.  

When I work on a piece I often construct a metaphor that will guide me through its composition.   I use an electronic dictionary, thesaurus, and encyclopedia to sprout the seed of an initial idea.   In this case, I began with the words "grain" and "particle."   The thesaurus led me to "iota" and the dictionary told me it was a noun meaning "a very small amount, a bit."   The dictionary also reminded me that "iota" is "the 9th letter of the Greek alphabet" and that it is of Phoenician origin.   A search of the encyclopedia under "Phoenicia" brought me to a picture of a galley ( golah   in Phoenician).

Further reading informed me that there is speculation that the Phoenicians used one of these ships to cross the Atlantic and visit the mouth of the Amazon many centuries before the birth of Christ.   If the speculation is correct, the Phoenicians would have predated Columbus' voyage to the New World by more than a thousand years.  

My metaphor was now in hand.   The shape of my piece would mirror a voyage from the Mediterranean to South America on a mythical ship named the "Golah Iota."   This tiny galley would experience, through my sounds, a journey from the calm waters off North Africa through heavy seas and winds to the tranquil shores of what is now Brazil.

The implementation of this model was accomplished with a chaotic function (the logistic difference equation):

X = P*X*(1-X)

In this equation, X varies from 0.0 to 1.0 and P varies from 0.0 to 4.0.   Here is the graph of the function:

With each iteration of the function, the previous output value for X is fed back to compute the next value.   As P increases, the behavior of the function increases in complexity.   When P is between 0.0 and 1.0, the functions "dies" (all output gravitates toward zero). Between 1.0 and 3.0, the output values for X converge to a single curve that ascends in value with the value of P.   At 3.0 the function bifurcates resulting a in limit cycle of two X values that oscillate.   As P continues to increase, the interval between the two values increases until, at 3.5, a second bifurcation takes place to produce a "four cycle." This behavior continues as P increases to about 3.6 where the cycles become so long and complex that they are difficult to follow.   This is the chaotic region.   In spite of the complexity, every value of P (even to differences in the tenth decimal place) has a characteristic structure that is clearly recognized as an analog to motivic variation.

In "The Voyage of the Golah Iota" and "Colony," I used a function that produced and arch form by interpolating P from 1.0 and 4.0 and back again over a period of time.   "Golah" was eleven minutes long and "Colony" is seven.   I used the golden section to determine the proportion between the rising and falling gestures.   The rise occupied the longer period.  

In "Golah," X values (the grains) were produced with a density of 10 per second when P was at 1.0 and 1000 per second when P reached 4.0.   The values of X where scaled and mapped onto a seven octave, micro tonal pitch range (approximately 192 tones per octave).   Sound was synthesized in 16 MIDI channels with two Yamaha TX816 synthesizers overlaid with two Proteus/1 modules.   The texture was then "smeared" with an Alesis MIDIVERB II.   The controlling program was implemented with MAX.

In "Colony," granular density is very much reduced because of the synthesizers used in its realization.   The "orchestra" here consists of two Emu Proteus/1 modules and a single Proteus/2.   The texture ranges from a density of 8 grains at the beginning and end to 48 grains at the peak.   This lower density and the generally longer duration of the grains may obviate the use of the term "granular." Since artistic ideas have a pleasant tendency to evolve, I'll leave the quibbling over precise terminology to the purists.

The title "Colony" is suggested by another method I used to generate pitch patterns.   In working on a book about algorithmic composition I have been investigating "genetic algorithms" (GA).   In a GA, the usual method is to begin with a population that is generated randomly.  

The initial population is then subjected to rules of evolution that include selection of "parents" based on prescribed characteristics of suitability and breeding of "children" for each subsequent generation.   Children inherit genetic features from their parents and, with small possibilities for mutation, future populations evolve.   At this point I will remind the reader of the logistic difference equation that I presented earlier:

X = P*X*(1-X)

Another popular name for this equation is the "Verhulst equation" after the mathematician who invented it to study the ebb and flow of populations under conditions of health and disease, feast and famine.

In a computer nothing is ever really random.   If we define our terms precisely we must say "psuedo-random."   The process of random number generation on a computer is deterministic.   What seem like strings of random numbers are actually small portions of a large cycle of numbers that will repeat after millions of iterations.   Each new number is made by applying a mathematical function to the previous number in the sequence.   A random seed simply specifies where to begin on the circle.   If we use the same seed, we will get exactly the same "random" results.   Changing the seed changes the sequence and thus gives the impression of a different instance of randomness. The two versions heard in tonight's concert differ because of the "seed" that is used to start the random selection of the first generation for the GA.   "Colony 110984" and "Colony 110994" use seeds that encode the month, day, and year into a single integer.   The first version relates to the founding date of the Society for Electro-Acoustic Music in the United States (SEAMUS) and the second relates to today's date.   The relationship is, of course, only intellectual.   The resemblance to biorhythms and astrology is purely coincidental.