5-band EQ preamplifier: adopt 5PCS JRC4558 op amp, each one is responsible for one frequency band and process the audio signal independently. 5-band separate control knob, easily to control and set the freqency range as you like. Bypass design suits more use: with bypass button to turn off EQ preamplification, the audio signal will output from IN to OUT directly without any processing, convenient to enjoy original sound.
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