Music Notation Software and Intelligence

As the saying goes, a little knowledge is a dangerous thing. This applies to music notation software as much as to anything else. The articles on this topic in this and the previous two issues of Computer Music Journal make it clear that notation programs can no longer be thought of as the toys that we believed them to be only a few years ago. Now that score preparation programs are growing up-perhaps this is even evidence that they are growing up-they're suffering from one of the typical problems of adolescence; they act as if they know everything. Why is this true, considering how much today's better programs know about rhythm, complex chords, instrumentation, and so on? The reason is that all this knowledge isn't much compared to what there is to know about common-practice Western music notation (CMN). This is a very complicated subject with many exceptions and subtleties. Lacking the space for an extended discussion, I'll have to rely on a few dramatic examples to make this point. Shown in Figures 1-4 are examples of cases in which famous composers of the classic-romantic period flagrantly violated important rules of music notation and yet produced results that are easily readable (playable) by most musicians. These examples are taken from my Ph.D. dissertation (Byrd 1984), which includes many more examples and a detailed discussion. In Figure 1, Johann Sebastian Bach changed time signature in the middle of a measure (from the Goldberg Variations)! Figure 2 shows a measure with no less than four horizontal positions for notes that are all on the same downbeat (taken from Johannes Brahms's Intermezzo op. 117, no. 1). The notes in the dotted quarter chords occupy three different positions; the first eighth note on each staff, in yet a fourth position, is also on the downbeat. Finally, Figures 3 and 4 are two very different ways of having two clefs in effect on a staff at the same time. The first is bizarrely obvious (from Claude Debussy's La Danse de Puck). The other-in the fourth measure on the lower staff-is so subtle that one really has to think about the 3/8 meter here (obvious everywhere else in the example) to see that the bass and treble clefs are both in effect throughout the entire measure (from Maurice Ravel's Scarbo from Gaspard de la Nuit). Why do these peculiar pieces of notation arise in the music of these highly respectable composers? The interesting thing is that there is really nothing very strange going on in any of these examples. In fact, it is easy to imagine someone playing through Figure 2 or 4 without even noticing anything unusual-and a listener to any of these examples would surely not notice anything unusual. Bach could have written the first example without a change of time signature at all, but it would have required tuplets and would probably have been harder to read. All of the other examples could have been written without any unusual notation simply by adding a third staff, but then the music would have required more paper (expensive for the publisher) and perhaps page turning (annoying for the performer). The point is that the supposed rules of CMN are not independent; they interact, and when the situation makes them interact strongly enough, something has to give way. It is tempting to assume that the rules of such an elaborate and successful system as CMN must be self-consistent. A problem with this idea is that so many of the "rules" are, necessarily, very nebulous. Every book on CMN is full of vague statements illustrated by examples that often fail to make the rule clear, but if you try to make every rule as precise as possible, what you get is certainly not self-consistent.