Something Old to Something New: From Bach to AI
April 6, 2017 § 5 Comments
Composers can spend their entire lives studying the music of deceased composers before them in order to find inspiration for their own compositions. They can then spend years drafting manuscript after manuscript before they finish their work. However, the process doesn’t end there. After music is composed, the composer still has to find musicians willing to play the piece and people willing to listen.
In Cloud Atlas, it takes Frobisher, a struggling composer, quite a while before he even finds inspiration through Arys for the Cloud Atlas Sextet. What if in the time that it took Frobisher to compose The Cloud Atlas Sextet, a computer program could immediately compose five thousand different pieces of music based on the composition style of Frobisher? What if Frobisher’s musical thoughts and ideas could be extracted from the source and recombined into an entirely new composition that still retained every musical nuance of Frobisher as a composer? In this case, Arys wouldn’t have even needed Frobisher; he could have just used the computer program to compose his music. What if I told you that this computer program exists and has composed thousands of different compositions in the style of other composers, and it has even combined the influences of multiple composers into its own unique voice?
In the 1990s, David Cope, Professor of Music Theory and Composition at the University of California-Santa Cruz, created the program Experiments in Musical Intelligence, or EMI for short. EMI is able to take the notes in existing music and convert it into data. The data consists of numbers corresponding to the frequency (pitch), duration (rhythm), speed (tempo), volume (dynamics), and articulation of each note, converting the entire composition into numbers. EMI then analyzes the all of the data, looking for patterns (i.e. “Note 50 tends to be followed by note 56 frequently,”) before being able to compose an entirely new composition based on the characteristics of the source music.
In addition these impressive feats, the compositions of the program are musically indiscernible from the compositions of its source composers when played by human musicians. A four part chorale for voice composed by EMI in the style of Bach has all of the characteristics and nuances of Bach’s chorales, from harmonic structure to melodic development. What’s even more impressive was even able to use Mahler’s music to compose an entire opera in the style of Mahler. Mahler didn’t even write operas. EMI eventually developed into the program now known as Emily Howell. Emily Howell has all the capabilities and the entire database of EMI, its prototype, but it additionally has an interface that allows David Cope to musically and linguistically give Emily positive and negative feedback on its compositions, essentially making Cope the teacher and Emily the student, except Cope is able to take all of the credit for the work. Sound familiar?
In order to further understand EMI/Emily Howell as both a program and a composer, it helps to understand music from an algorithmic perspective through a brief explanation of algorithmic composition. Since the beginning of written music and even perhaps before then, music composition has historically had different sets of rules to be followed. At the most basic level, a note may sound better when played with a specific note as opposed to another, and one sequence of notes may sound better than another sequence of notes. Because of this, a formal set of rules was eventually developed. The success and genius of prolific composer Johann Sebastian Bach posthumously spawned the foundation of tonality for almost all of Western Music. This algorithm dictated rules such as which chord progressions to use (harmonic function) and how the notes within those chords move to the next note. This “Tonality Algorithm” is in fact so established that it is a common exercise in music theory to harmonize a melody in the style of Bach. Moreover, this algorithmic perspective can be applied to musical improvisation as well as composition. In Chord-Scale Theory, specific scales are to be used in correspondence with specific chords (i.e. the notes in a major scale are conventionally played over a major chord).
It takes Emily/EMI mere moments of analysis to develop algorithms for every composer that it studies, while it took humans hundreds of years to analyze Bach and develop an algorithm for the foundation of tonal harmony. Because of this, EMI/Emily can develop its own musical voice by using the influence of multiple composers to in a sense, recombine the musical DNA of the composers until finding its own unique composition style subject to David Cope’s approval and modification.
The invention of Emily/EMI raises questions pertaining to the authenticity and legitimacy of music. If EMI composes pieces that pass Turing Tests such that a listener cannot distinguish whether or not the piece was composed by Stravinsky or EMI, does that challenge the notion that music requires a human element to be viewed with merit and virtuosity? Does Cope still retain the title of composer when he teaches EMI to compose a symphony? Is Cope a composer, a programmer, or both?
“In twenty years of working in artificial intelligence, I have run across nothing more thought-provoking than David Cope’s Experiments in Musical Intelligence. What is the essence of musical style, indeed of music itself? Can great new music emerge from the extraction and recombination of patterns in earlier music? Are the deepest of human emotions triggerable by computer patterns of notes?
“Despite the fact that Cope’s vision of human creativity is radically different from my own, I admire enormously what he has achieved. Indeed, this lovingly written book about a deeply held vision of musical creativity should, I think, earn its place as one of the most significant adventures of the late twentieth century.”
–Douglas Hofstadter, author of “Godel, Escher, Bach” and “Fluid Concepts and Creative Analogies”
A friend of mine told me that the human essence in music is absolutely essential to a composition’s legitimacy. However, when that “human essence” is able to be broken down into numbers and modified into an art that is completely new and unique in its own way, does that not undermine the “human essence” that is so precious to us?
As a musician, this invention and breakthrough in computer music is absolutely terrifying to me. If anything I do as a musician or composer can be done exponentially faster by a computer and be just as much of a “Paolo Dumancas Composition” as my actual compositions, could my passion for music, such a significant part of my identity, be inevitably undermined and rendered obsolete?
Cope, David “Computer Models of Musical Creativity” (2005), MIT Press.