Equal-loudness Contour
The smiley face curve is roughly analogous to the frequency response of human hearing as charted in the equal-loudness contour, and has been compared to loudness compensation circuitry in that it increases the relative power of high and low frequencies without increasing the midrange power. In order for a sound system to be heard properly by humans, it should have an equal-loudness contour applied to it when it is performing at low sound pressure levels, then the curve should gradually flatten out as it gets louder.
Read more about this topic: Smiley Face Curve
Famous quotes containing the word contour:
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