Sunday, December 16, 2007

Piano diary #4: intervals key to sight-reading

Sight-reading! Tell me about it ... ! I've got three months (until the Grade 1 exam in April) to get it right.

I started by trying to learn the notes under each finger. Put your right-hand thumb on D, and then the fingers touch E, F, G, A. If the sight-reading test starts on D, and you are asked to put your thumb on D, then you can read the next note on the score and, if you know which finger is above that note, just play it. (You don't have to move your hands at Grade 1).

Two things subvert this approach. Forgetting the sharps and flats of the black notes, there are seven possible positions for the thumb to be placed, A-G: the pattern of notes under the fingers obviously varies with each. That’s 7 * 5 = 35 patterns to learn.

But of course you can’t ignore the sharps and flats - because they’re everywhere. And of course, they are built into the key signatures themselves.

And in non-test music, as bar follows bar, you are frequently told to move your hand position, which throws everything off. I’m not saying it’s impossible, but the procedure is utterly ponderous:

- see the next note on the score - suppose it’s “a”
- name it to yourself (A)
- recall where your thumb (“1”) currently is (D)
- recall that in that position, A is under the little finger (“5”)
- depress the little finger.

There is a better way.

A few months back, the book I was studying made a big fuss about intervals (2nds, 3rds, 4ths, 5ths, etc). You were meant to look at adjacent notes and “by inspection” say what interval encompassed them. For example, a “D” followed by an “A” is the interval of a fifth. At the time, I had little idea of the point of this. But ...

With a little practice, it is possible to read the pattern of intervals straight off the score. We all spontaneously do it for 2nds, where the notes follow each other up or down the scale. If you can internalise the fingering of an interval (thumb to little finger typically spans a fifth, for example) then playing intervals is pretty direct. The new algorithm is simply this:

- identify the interval between current note and next note
- shape the fingers to encompass that interval and play it.

Much faster and permits controlled look-ahead.

In a certain sense, you have to know everything - including which note your finger is currently depressing. But moving to an interval-based approach to sight-reading really unlocks it for me.

The obvious metaphor is differential calculus. With intervals, playing the score is really like computing:

f(x + dx) = f(x) + f’(x)dx*,

so that next-note = current-note + interval.

* Or more correctly, difference equations. The key point is that the interval approach is invariant as regards differences in key (subject to managing accidentals - sharps and flats - correctly), pun unintended.