Try it!

What does your brain hear? Sounds with higher frequency are interpreted by your brain as being “higher in pitch” and sounds that are lower in frequency are interpreted as “lower in pitch”.

A piano is a frequency generator! Press the piano keys below to hear what it sounds like and see the different frequencies.

Our piano doesn’t sound like a real piano, why? Our piano plays a pure tune (one frequency) for each note, but a real piano plays many frequencies (harmonics) at the same time for the same note. How quickly the amplitude changes also makes a piano sound like a piano. We’ll learn about amplitude next.

Notice that we show the sound waves for a 2 millisecond window. A millisecond is 1/1000 of a second. Also notice how every octave the number of waves (peaks and troughs) doubles: the lowest (left) key shows 1 wave, while the highest (right) key shows 4 waves since it’s two octaves higher.