I have mouthed off quite a lot about what it means to write music for a computer’s idiom in meatspace. I think I’ve been mouthing off about it for as long as I’ve been writing music. I don’t know why I haven’t written much about it, because it very much informs how I think about composition for computers.

When we talk about composing, we speak about writing for an instrument’s idiom. Instruments have different capabilities, different acoustical responses in different ranges, different physicalities, etc.

An example given by onlyocelot over at yahoo answers addresses playing traditional string music on Carleen Hutchins‘ experimental violin-family instruments:

the tenor violin, for all it’s design improvements over the viola, sounded much worse. The viola had a very pronounced resonance around Bb, and Mozart had written to this strength. The tenor violin lacked this characteristic peak, and the viola sonata, played on the tenor violin, just lacked ‘something’.

Part of writing for an instrument’s idiom is making its weaknesses into strengths.

Photo by Jason Hollinger

Physicality matters. It’s one thing to ask for a smooth glissando on a trombone and another thing to ask for a glissando on a flute. Sure, I’ve heard great flautists play a smooth glissando, but it’s a lot less idiomatic than playing one on a trombone. Asking for chords on a piano is a different thing than asking for chords on a clarinet. And if you ask for a chord on a violin, you’d best make sure you haven’t picked notes that would require that the first and third string be played but not the second.

Photo by Infrogmation

I was chastised as a composition student for writing a trombone piece that worked beautifully on the student instrument that I’d borrowed to write it with that didn’t work on a professional quality instrument because there were different physical considerations that I hadn’t anticipated. Even I could play the piece on the student instrument, but the virtuosic performer who I’ve seen doing pretty amazing things was severely hampered because he was playing an importantly different instrument. If I were to dig the piece out and give it to anyone, I’d have to specify that it is really only for student trombones and not trombones in general.

Photo by Mark Kimpel

There’s absolutely interesting music out there that explicitly plays with the notion of violating an instrument’s idiom. Composer A writes a piece of music for bassoon. She thinks a lot about bassoons. She thinks about the basson’s physicality, it’s strengths and weaknesses, its different acoustic responses at different ranges. Composer A writes a piece of music about possibility and impossibility that plays with violating the bassoon’s idiom and examining what the performer will do in differently interesting impossible situations. Composer B  comes up with a really nice piece of music and runs it through different midi instruments and likes how it sounds on a bassoon. He declares the piece to be for bassoon. It turns out that it’s got some bits that are impossible to play. We evaluate the piece from composer A very differently from the piece from composer B. Whether or not we like composer A’s piece, we think composer A is more skilled than composer B.

I hope it’s been changing over the last several years, but when I began to study computer music, computers were widely regarded as neutral. I’ve been on the receiving end of some very condescending platitudes about how horrible it is that I even think about computers or pieces of software as having  idioms because because computers are all flexible and neutral and we can do anything.

Photo by Ran Yaniv Hartstein.

Computer musicians pour all kinds of resources into trying to get computers not to behave like computers. We’ve got pitch trackers and score followers and artificially intelligent listening systems and all kinds of things. Now I’ll be the first to grant that these are really fun research projects to geek out on. Who doesn’t like to get their geek on? But at the end of the day, if a composer disregards the computer’s idiom, the computer requires a babysitter at the concert. A skilled performer who could be having way more fun playing an instrument has to sit there with the score and make sure the computer is doing its job and push a button when the computer misses its cue. I’ve been to a lot of concerts like this and I’ve seen the babysitters have to intervene an awful lot.

Like composer A and composer B above, I think it’s a very different thing if I write a piece of music to test/exploit/break my colleague’s score following algorithm than if I write a piece of music that pretends that a computer is somehow an idiom-free instrument. Writing a piece that confronts, exploits, tests, breaks my friend’s score following algorithm would both give my friend some interesting data to work with on his next version and would be written with breaking in mind and would have a mechanism inherent to the piece to let the breaking happen gracefully.

Ignoring the computer’s idiom, I might, like composer B, have a perfectly nice piece of music that sounds cool when the computer is supplemented by a babysitter. But I won’t have explored what it means to write for a computer.