Ladies and gentlemen, I’m about to go all “teacher” on you. We’re going to talk about interesting facts about pitch, and the way that pitch relates to our lives. If you can survive this entry, there will be a pleasant surprise at the end! Woot!
This post came into my head as I was sitting here drinking my morning coffee, and a passing truck beeped its multiphonic (more than one pitch) horn. Immediately I exclaimed, “That truck beeps the opening chord for Vetiver’s Hey Maureen!!!” The one person sitting near me rolled their eyes. “No, I swear!” I searched my iTunes folder and pulled up the file. As I pressed play, the person looked at me like I was a freak, but admitted that yes, the beep was the opening chord of Hey Maureen.
I don’t have “perfect pitch.” For those of you who aren’t music nerds, “perfect pitch” is the ability to hear a note and identify it immediately. I do, however, have excellent pitch memory. If I’m singing a song without the radio, for example, I’m very likely to sing it in the same key just off my head. Or, if the radio DJ announces a song that I know is about to play, I’ll start imagining that song in exactly the same key as it comes on. Many, many musicians do this. As far as I know, pitch memory isn’t something that we’re taught. It either happens… or it doesn’t. Perfect pitch, on the other hand, is something that can be taught to anyone with a decent sense of pitch memory. Want your child to impress people at parties and annoy all his or her musician friends? Teach them perfect pitch when they are babies! The thing is, “perfect pitch” isn’t perfect. Why? Because pitch evolves!
I’ve lost you now, I’m sure, and the two of you who are still reading are about to go cross-eyed. Welcome to the wonderful world of the physics of sound, people! Pitch is determined by the size of a sound wave. A lower pitch will have a wider sound wave, like so:

A higher pitch will have a narrower wave, thusly:

Obviously, the waves can be any possible size, so an arbitrary “smallest distance” between pitches was chosen a loooooong time ago. In Western music, this smallest distance is called a half step, or a minor second. Anything between a half step is usually called “sharp” or “flat” (too high or too low, respectively).
Here’s where it gets fascinating (or, to most of you, boring as all hell). When musicians are sitting in an ensemble, our instinct is to try and hear our own sound. Hearing oneself individually is nearly impossible, so we unconsciously play a little bit sharp (too high) to distinguish our own sound. You can imagine what happens next: our neighbor, trying to hear his or her own sound, plays a tiny increment higher than we do. And so forth and so on, until the entire ensemble is playing just slightly higher than it was two years ago. These shifts take years to notice, but our standard of “correct” pitch gets higher and higher. For example, when I purchased my flute ten years ago, the note A was “correct” at 440 Hertz, meaning that the sound wave makes 440 cycles per second. When I played in an orchestra concert this weekend, we tuned to an A that was 442 Hertz. Two extra cycles of a sound wave might not seem significant, but when you consider that that’s a change over one decade, and music history has gone back thousands of years… it’s pretty stunning to consider how much the note A has changed. And when we think back to the concept of “perfect pitch,” it demonstrates why this is a fairly useless skill to have.
Let’s say you developed your perfect pitch 40 years ago. The pitch standard at that time would have been completely different than the pitch standard today, meaning that the pitch you memorized as “perfect” is lower than the pitch we consider “correct” today.
The moral of this story, aside from the fact that I am the most gigantic dork on the face of the earth, is that pitch memory is far more useful than “perfect pitch.”
Aaaaaaand since you read all of that… TOMORROW WILL BE MY 500TH POST! It’s strange to me that I’ve only published 499 posts in the past two years. I feel like I’ve written more than that, but so it goes. In honor of the Mighty 500, tomorrow I will be holding a contest. I’m not going to tell you what it is, but be prepared to be creative and rhyme. The prize will be totally fabulous (if I do say so myself), so bring your game face, people! The post will go up at midnight tonight, and the contest will remain open until 11:59 p.m. Pacific time tomorrow, May 8, 2008.
I’m even more excited about this than I am about soundwaves.