Crossover Car Audio EX4.6 PRO 4 Way or 3 Way Electronic Crossover 9 Volts, 4 in 6 Out RCA Channels Car Sound Processor. Crossover slope rate: Butterworth 12 db/Octave. Bass Equalizer: provides a “gain attenuation” 0 to + 12dB at the center frequency of 45Hz.
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