Chapter 5
Music Theory: Why Note Names Repeat
Two different pitches can have the same note name for much the same reason that “dark red” and “light red” are both considered red.
Guitar example
The guitar’s low E string produces about 82.4 Hz, while its high E string produces about 329.6 Hz. Their frequencies are separated by a factor of four: start at 82.4 Hz, double it to 164.8 Hz, then double it again to reach 329.6 Hz.
Those two doublings are why the low E sounds like a darker shade and the high E sounds like a lighter shade of the same note. They are different pitches, but both are named E.
Bass example
On a standard four-string bass, the open E string produces about 41.2 Hz. The E at the 12th fret produces about 82.4 Hz—exactly twice the frequency.
That doubling is why the open E sounds like a darker shade and the 12th-fret E sounds like a lighter shade of the same note. They are different pitches, but both are named E.
Remember how doubled frequencies sounded as though they “just fit” back in Chapter 1? Your ears hear every doubling as another version of the same note. This distance is called an octave, and the note name repeats at every octave.
Guitars and basses usually have fretboard dots, also called dot inlays, that help you see where a note name returns in a lighter shade.