Equal-Loudness Contours

Equal-loudness contours are graphs that illustrate how our ears perceive different sound frequencies at various loudness levels. Because our hearing is more sensitive to some frequencies (like those in speech and music) and less sensitive to others (such as very bass or treble sounds), sounds must be at different intensities to be perceived as equally loud. These contours help us understand how loudness perception varies with frequency, ensuring audio systems and hearing tests can be calibrated for accurate and natural sound experiences. Essentially, they show the relationship between loudness and frequency for human hearing.