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18 March 2009

The Magic Tuner-Metronome


I learned a bunch today in the waves-in-a-musical instrument lab. (See yesterday's post for details.) For one thing, I learned that a tenor recorder is pitched in F. That means that when you think you're playing a C, you're actually playing an F. How did I learn that?

You might recall that I proposed to determine the correct octave being played by comparing the recorder's note to that played by a digital frequency generator. Three problems emerged:

(1) I only had an analog freqency generator available, that could give me a freqency to only about +/- 20 Hz; and

(2) My students were so bad at recorder playing that I'll bet THEIR frequency varied by at least that much, too.

(3) I used to have a pretty good ear for pitch, back when I was in choir and marching band. However, I discovered that matching a pitch with the frequency generator in a loud room was quite difficult.

After 20 minutes of putzing, someone asked if they could check their pitch with Charlie's tuner. What?!? Charlie has a tuner? Back when I was in band, a tuner was an enormous, bulky, expensive device. It might be able to tell you whether you were sharp or flat, but *you* had to tell *it* what note you were playing.

Amazing, the progress of technology. Charlie pulled a calculator-sized box out of his guitar case. We held up the box to the recorder, a student played -- or tried to play -- a note, and the box told us: That's a C4, which we know to be 262 Hz from our chart! When the student played the high C, the box registered as a C5, 523 Hz.

That's how I found out that the tenor recorder was pitched in F. The box told me so.

Anyway, I instantly went online to order one of these magic boxes. The item is a Boss TU-80C Chromatic Tuner & Metronome, $25.68 (including shipping) from amazon.com. I highly recommend you get one of these things if you do today's experiment.

GCJ


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