Manufacturer Presets
Some audio equipment manufacturers have accommodated the user by engineering a smiley face curve into a product. dbx, Inc. offers several smiley face curve presets in their digital graphic equalizer product line called DriveRack. Jim Dunlop offers a direct box intended for bass players that includes a preset labeled "color" which engages a smiley face curve. Neither of these products prevent the user from adjusting the equalizer based on the sound that is actually heard rather than relying on a predetermined visual image.
Alpine Electronics has offered for sale a product for car audio systems that works to counteract any smiley face curve that was applied to a car's factory OEM sound system, along with an analysis feature that adjusts for road and vehicle noise. Empeg Car, a digital media player, includes a "Loudness Control" feature that is described as adding a "smiley face" curve automatically" at low sound levels but which is used to lesser and lesser degrees as the car sound system's volume is increased. This describes an equal-loudness contour circuit.
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