7. GAIN/LEVEL CONTROL (FRONT-REAR)
This control is used to match the input level of the amplifier to the output level of your head unit. We recommend the method below, as failure to follow these steps may damage the audio system.
1.Turn the amplifier Gain to zero
2.Turn the volume of the head unit to ¾ and the bass and treble to zero
3.Adjust the amplifier Gain/Level control until the desired maximum volume is achieved without distortion.
4.Make fine adjustments to tune your install.
8. HIGH PASS CROSSOVER FILTER
Set the crossover switch (10) to HP and turn this control to 65Hz or above when using speak- er’s smaller than 6 x 9”. When a subwoofer is used in the system, this feature is designed to filter out all low bass frequencies that only subwoofers should produce. See specification table for adjustable frequency range
9. LOW PASS CROSSOVER FILTER
Set the crossover switch (10) to LP, ensure the crossover frequency is set at 100Hz or below. This feature must be used with a subwoofer to filter out all mid to high frequencies that only full range speakers should produce. See specification table for adjustable frequency range.
10.HIGH PASS - FULL RANGE - LOW PASS SWITCH
High Pass See Note 8
Full Range
This setting is for large speakers (e.g. 6 X 9”) or speakers when a subwoofer is not included in the system. The amplified audio signal is not filtered so the full range audio signal is sent to the
speakers. 
Low Pass See Note 9
11.SUBSONIC FILTER (EN-3001 ONLY)
This is a variable control that filters out all subsonic bass frequencies below the set point. These are frequencies that are not audible. These frequencies can damage subwoofers. See specification table for adjustable frequency range.
12. BASS BOOST (EN-3001 ONLY)
This control adjusts the bass boost at 45Hz, from 0 to +18dB. Start from 0 and slowly in- crease to the desired level. Use this control with extreme care as failure to do so may result in damage to the subwoofers.
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