.Phase Switches Invert the Phase of Individual Outputs, Output Mute Switches for All Individual Outputs .Adjustable Low Frequency Delay for Time Aligning Speaker Stacks, Constant Directivity EQ Smoothens the Response of CD Horns Above 3.5khz .Mode Indicator LEDs Provide Quick Visual Display of Operating Mode, Peak Limiter with Independent Threshold Control and Peak LED .4 Segment LED Input Meter Allows Easy Gain Adjustment, High Quality 41 Position Detent Pots and Backlit Switches .Precision Linkwitz-Riley, 24 dB/Octave filters