The Q-Spand PRO 4-channel rackmountable professional DJ mixer is loaded with pro features from top to bottom. These include a 3-D stereo button with width level knob for highs and TRU BASS button with bass level knob for lows; Fader Q start; gain, bass, mid, and treble control for each channel; 3 phono, 4 lines, 4 auxiliary, and 3 mic inputs; and balanced XLR outputs. Then it adds Stream Flow LED indicators on each channel and separate volume for each microphone. WOW by SRS Sonic Enhancer for richer 3-D sound. Take advantage of American Audio"s commitment to produce the best and highest-quality audio products possible at an affordable price.4-channel, 19-inch professional DJ mixer 3 phono, 4 lines, 4 auxiliaries & 3 mics 3-D stereo button with width level knob (Highs) TRU BASS button with Bass level knob(Lows) Q-Start WOW by SRS button - Sonic enhancer with 3 dimensional sound Easy access auxiliary input on front of the mixer to plug in MP3 players, or satellite radio receivers Fully adjustable crossfader curve Volume, treble and bass control for each mic Stream Flow LED indicators on each channel Trim output adjustment on rear Improved mic circuitry and longer lasting line faders Mic attenuator control on rear panel Balanced XLR outputs Gain, bass, mid, and treble control for each channel