* A tuning fork is a specially shaped piece of metal which produces a specific note when you hit it.
* If you look back to the photo of the piano keyboard in chapter 1 , you will see that the word “adjacent” is a little complicated for a piano. All the white keys look adjacent to each other because the black keys are not long enough to separate them properly. The fact that the black keys are short is merely to help with the ergonomics of the instrument. As far as the sound is concerned, the white notes B and C are adjacent to each other, but F and G, for example, are not—they are separated by F#.
* We could find out what the actual ripple shape for a closing door looks like by attaching a microphone to a computer and asking the computer to draw the changes in pressure experienced by the microphone (a microphone acts rather like an ear—it has a small part inside which moves in and out as the pressure of the air goes up and down). The actual ripple pattern would probably be even more complicated than the one I have drawn here.
* When we say “cycles per second,” we mean how many times the string moved through a complete cycle in one second. A complete cycle would be, for example, starting in the middle, moving over to the right, back to the middle, over to the left and then back to the middle.
* The use of frets to shorten guitar strings is discussed here.
* Traditionally the organ is referred to as a keyboard instrument and the thought-police will take you away in handcuffs if you call it a wind instrument. So I’m calling the second three instruments “wind in tubes”—let’s all hope I get away with it.
* Actually, each hammer hits two or three strings—all tuned to the same note—for extra loudness, but I will refer to “a string” as if there was only one in each case.
* The first two notes of “Somewhere over the Rainbow” are an octave apart.
* Guitarists call “pinging” “playing harmonics.”
* I will call this the key note, or team leader, but it is traditionally called the tonic, which is based on the Ancient Greek and Latin words for “tone.”
* Even though the sharp/flat notes have two names, it would be considered very peculiar to name the notes of the “A” major scale using “flat” names like this:
A—B—D
—D—E—G—A—A
This way of naming notes in a key is not used because some letters appear twice (“A” and “A,” “D” and “D”), which is confusing. We use only either “flat” or “sharp” names for each key—and choose whichever system uses all the letters, like this:
E Major: E, F#, G#, A, B, C#, D#, E
B Major: B, C, D, E, F, G, A, B
* Muscular memory is explained here.
* I say this here because that’s what is supposed to happen. In many cases, however, I have seen professional conductors simply making pointless dramatic gestures which indicate nothing to the musicians but look good to the audience.
* Galilei and Chu Tsai-Yu probably started by calculating the increase in frequency between two adjacent notes. From this you can work out how much shorter the higher string should be. I have used the shortening of strings because it makes the discussion easier to follow. Our two wise men calculated that we needed an increase in frequency of 5. 9463 percent between two adjacent strings: for example, if G has a frequency of 392 Hz, then the note one semitone up (G sharp) has a frequency of 105.9463 percent of 392, which is 415.3 Hz. To achieve this, if the strings are otherwise identical, the G sharp string will have to be 94.38744 percent the length of the G string.