In what unit is sound amplitude typically expressed?

Sound amplitude, which refers to the magnitude of sound pressure or intensity, is typically expressed in decibels (dB). Decibels provide a logarithmic scale that captures the range of sound intensity that humans can hear, from the faintest sounds to very loud noises. This unit is particularly useful because it allows for a more manageable representation of the vast range of sound levels, making it easier to relate sound intensity to human hearing perception.

For instance, a change of just 1 dB can be just perceptible to the human ear, while increases of 10 dB are generally perceived as roughly doubling the loudness of a sound. Other units mentioned, such as hertz, amplify electrical signals, and watts are measures of power, which do not directly pertain to sound amplitude or intensity in the same context as decibels do.