The pitch of a sound (from a low bass to a high shriek) is related to the amplitude of the sound waves that reach the eardrum.

Sound Waves

Waves of sound that propagate through air or other materials, perceived when they make contact with an individual's or an animal's ear.

Amplitude

In physics, it is the maximum extent of a vibration or oscillation, measured from the position of equilibrium.

Pitch

A term that can refer to the perceived frequency of a sound, often described as how "high" or "low" a note sounds.