Computers Mimicking Composers

The history of music and technology is a long and mostly productive one. The invention of nylon in the 1930s and the development of practical uses for it during the Second World War was a life-saver for classical guitarists who previously had used catgut for the treble strings. During the war, Segovia has commented, it was almost impossible to find gut strings!

Since the 1950s, however, there have been many other intersections of technology and music. The use of magnetic tape for sound recording was another innovation of the 1930s and it has had many benefits. Previous media for recording had much poorer fidelity than was possible with magnetic tape. It was also possible, with a razor blade and sticky tape, to edit the magnetic tape. Composers soon saw the possibilities and a whole generation of composers such as Karlheinz Stockhausen and Pierre Schaeffer experimented with "tape music" that is to say, music created using the possibilities of magnetic tape. You can record natural or musical sounds and splice them together any way you want which is called "musique concrète" because a number of French composers were the first to try it. A very famous example is "Revolution No. 9" on the Beatles' White Album.

Of course, magnetic tape was just one technological tool composers discovered. There was a whole panoply of other devices that went together to produce "electronic music" or music synthesized from electronically produced sounds. The famous piece by Stockhausen Gesang der Jünglinge combines both approaches as it uses recorded vocal sounds and electronic sounds.

Most popular music today uses a wide variety of technology including digital recording, which has replaced magnetic tape, synthesized sounds, electronic instruments including not only electric guitars and keyboards, but also drum machines and computerized editing programs such as Auto-tune which corrects mistuned sung notes.

The latest trend is towards automating, computerizing, the composition of music. Several attempts have been made, not too successfully, but the most persistent current one is by Francisco Vico as a project in artificial intelligence at the university in Malaga, Spain. I previously posted about this here when the Guardian had an article on the project. Now the BBC has a new story on the project, called Iamus. Alas, this article lacks the common-sense approach of the previous story. In the video clip at the beginning, Prof. Vico states that their aim is to "make a computer that can mimic man when it comes to composing music." I was taken to task in a comment on my previous post for characterizing the project as an attempt to "ape human creativity" but as you can see, this is exactly the goal. At the end of the video clip, the narrator goes right over the edge saying that "Iamus is a landmark because ... what it writes cannot be differentiated from music written by a human being." I'm not certain, but I think this is a translation of the remarks of Prof. Vico.

This last statement is not quite as ridiculous as it sounds because the music composed by Iamus can most certainly be mistaken for music by quite a number of modern composers. The passage being played by the orchestra in the clip, for example, sounds rather like "The Housatonic at Stockbridge" from Three Places in New England by Charles Ives.

The difference is that while the music by Iamus sounds vaguely like the string texture of the Ives, what is missing is Ives' paraphrase of the hymn tune "Dorrance" which is woven through the texture. The truth is that Iamus is programmed to generate "countless" examples of modern sounding music. Brief segments of these compositions are not easy to distinguish from actual modern music. The article in the Guardian has a link to a "Turing Test" where you are invited to identify the music written by Iamus among five brief selections. Here it is. With less than a minute, and given the musical 'language' of modernism, it is not easy to do! A lot of modern music sounds pointless and directionless over a brief span. Some of it sounds like that over the long term as well! But the music Iamus writes really is pointless and directionless because the only actual agency involved is that of the programmers. The computer itself, of course, has no intentions and can give no direction to the music.

So my conclusion is that the interesting experiment of Iamus does not so much tell us that a computer can compose music, but rather the reverse, that some modern compositions sound no better than music more or less randomly generated by a computer.

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The Computer as Composer

Just a week ago there was an interesting premiere from the Centro de Tecnología de la Imagen - Universidad de Málaga. The composer of the music performed is a computer program named Iamus. Here is an article in the Guardian on this and on an upcoming CD to be released in September. Here is a link to a video of the recent concert. For your amusement, you can take a "Turing Test" in which you have to identify which of five musical clips was composed by Iamus. Here it is. Don't worry if you guess wrong--I did!

The article in the Guardian has a brief history of attempts at computer composition in the past and the meager results, accurately described as "Michael Nyman on a bad day." Of course, I know some music by student composers that also sounds like Michael Nyman on a bad day! One of the things we can say is that the task of creating a computer program that can compose music is rendered much easier if, instead of trying to imitate Bach or Beethoven, you use as your model Stockhausen or Ligeti. Due to the kinds of procedures some composers developed in the 20th century, which include aleatoric ones (follow the link for the details, but it boils down to using chance procedures), just writing a program that generates random notes and rhythms could easily sound like something by Cage or Xenakis. Why? Because they used random procedures.

Now obviously the computer program Iamus is doing something quite different. The interviews with the people involved (which come before the concert in the clip) indicate that they are using 'biomimetic' procedures. Here is quote from the Guardian article that reveals a bit about how it works:

Iamus – named after the son of Apollo who could understand the language of birds – composes by mutating simple starting material in a manner analogous to biological evolution. The compositions each have a musical core, a "genome", that gradually becomes more complex.

"Iamus generates an initial population of compositions automatically," Vico says, "but their genomes are so simple that they barely develop into a handful of notes, lasting just a few seconds. As evolution proceeds, mutations alter the content and size of this primordial genetic material, and we get longer and more elaborated pieces." All the researchers specify at the outset is the rough length of the piece and the instruments it will use.

"A single genome can encode many melodies," explains composer Gustavo Díaz-Jerez of Musikene, the Higher School of Music of the Basque Country in San Sebastian, who has collaborated with the Malaga team since the outset and is the pianist on the new recordings. "You find this same idea of a genome in the western musical canon – that's why the music makes sense."

Does the music "make sense"? The program is certainly generating themes that return and are varied, such as the trill figure in the piano piece Colossus, the first one in the concert clip. But though recurring themes are a characteristic of musical composition, I think we can demand a bit more. The harmony, especially at the end of the piece, seems to make little sense. Mind you, I can think of a number of 20th century pieces where the harmony is just as nonsensical. It is remarked in the Guardian article that the program can generate these pieces "endlessly". Well, in that case, we need to have some way of evaluating the music to decide what is worth performing and what not. Right now, the reason to perform and listen to this is "historical" value. If indeed this is music worth hearing, and it is the first music worth hearing to be composed by a computer then this is of historic interest.

But we can dig a bit deeper. The question of agency is always important. Who is the responsible agent for this music? Obviously the technological center at the University of Malaga, specifically the leader of this project, Dr. Francisco Vico, a professor of computer science. His interest is obvious: what a coup for a computer scientist to devise a computer program that can ape human creativity! The performers, who include the London Symphony Orchestra under the direction of Lennox Mackenzie, have probably accepted the engagement because it seems like a cool project. Mackenzie offers some aesthetic criticism of the music:

 "I felt it was like a wall of sound," says Lennox Mackenzie, the LSO's chairman. "If you put a colour to it, this music was grey. It went nowhere. It was too dense and massive, no instrument stuck out at any point. But at the end of it, I thought it was quite epic." 

"The other thing that struck me," Mackenzie adds, "was that it was festooned with expression marks, which just seemed arbitrary and meaningless. My normal inclination is to delve into music and find out what it's all about. But here I don't think I'd find anything." 

"It went nowhere."  Well, yeah! That's the problem with the piano piece Colossus: it also goes nowhere. Presumably because the programmers couldn't figure out how to program in the idea of direction in music. "Festooned with expression marks, which just seemed arbitrary and meaningless." Didn't just "seem", they are arbitrary and meaningless! See, here is the obvious truth: art only has meaning and direction--intention--when someone means something by it, expresses something with it. If a piece of music has direction and expression, then it is because of human agency. What we have here is an elaborate fake of music to show off the programming skills of Francisco Vico and his team. The only human agency comes either from the programmers or from the performers. If you put a reasonably plausible score in front of a pianist, he will do his darnedest to try and squeeze some expression out of it. As we hear in the concert video.

Just for fun, let's listen to one of those previous attempts at computer composition, programmed by composer David Cope.

Yep, Michael Nyman on a bad day...

I think that these sorts of experiments are actually very useful because they underline for us what is actually important about a musical composition: it is not so much the rules or procedures as it is the human agency. And if some avant-garde compositions cannot be distinguished from music composed by a computer program, then so much the worse for the avant-garde!

UPDATE: For those interested, here is a brilliant discussion of how computers actually work, with lots of detail. I think reading this rather lengthy essay will show pretty clearly why a computer cannot compose music, though it can deliver an interesting fake.

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