3 Band Graphic Equalizer

Posted on Feb 5, 2014

Using a single op-amp this easy to make equalizer offers three ranges, low frequency, mid frequency, and high. With component values shown there is approximately +/-20dB of boost or cut at frequencies of 50Hz, 1kHz and 10kHz. Supply voltage may be anything from 6 to 30 Volts. Maximum boost 20dB is only realized with maximum supply voltage of 18 Volt

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