What does the term 'Sound Pressure Level' (SPL) refer to?

The term 'Sound Pressure Level' (SPL) specifically refers to a reference level of sound pressure and is typically measured in decibels (dB). SPL quantifies the pressure variation in a sound wave relative to a reference pressure, usually set at 20 micropascals, which is considered the threshold of hearing for most individuals. This concept is crucial for understanding how sound is perceived by listeners and is often used in diverse applications such as acoustics, audiology, and sound engineering.

SPL is particularly significant when assessing hearing disorders, as it provides a standardized way to express how loud a sound is relative to the quietest sound that can be heard. The utility of this measurement lies in its ability to convey the intensity of sound in a manner that accounts for the logarithmic nature of human hearing sensitivity.