This is a nice little unit. The Sound Storm Laboratories S4EQ 4 Band Graphic Equalizer with a Subwoofer Crossover and Input Gain control with a Master Volume Control allows you to input a sound source into this unit and then feed the signal on into amps for the speaker drivers and control these sounds with a equalized control point. The Subwoofer crossover is adjustable across a band of frequency of 40 to 150 Hz. which allows you to tune your sub feed for the best sound for your use.
