MTX Audio MXA4002 - Manual (Page 10)

Located on the Input Panel, the objective of input GAIN adjustment is to match the output of
the source unit with the input of the amplifier. The output voltage of individual source units
can vary.Some source units have an output of 200 mV and others have 5 Volts or more. To
cater to these variations, the amplifier has an adjustable gain level that ranges from 100 mV
to 5 volts. Adjusting this control requires some experimenting. Basically, you want all the gain
at the beginning of the system, NOT at the end (amplifier). Turn your source unit up and keep
your amplifier gains at the minimum lowest possible setting
(counter-clockwise) with maximum output. This will give you the best sound and s
ignal-to-noise ratio.
Besides better sonic reproduction, proper input gain also helps to prolong the reliability span
of your amplifier by eliminating excessive internal temperature generated by
incompatible source unit output and amplifier input.
Note : Turning the input gain up does not indicate more power. Just more noise. The input
gain control is not a power control. If everything is in order, complete the installation by recon-
necting the battery ground to the vehicle chassis.
If the Remote Gain is used, connect the plug of the Remote Gain to the port on the panel of
the amplifier.
1. Turn the Input GAIN all the way down (counter clockwise).
2. Set the volume control of the source unit to approximately 3/4 of its maximum output.
3. Turn the balance control of the source unit to its center position (flat).
4. Leave the tone (bass/treble) controls at their usual position.
5. Play a CD or tape track with great dynamic range.
6. Use the Bass Boost Control on the amp to enhance the bass performance (if desired),
not the bass on the head unit.
7. To locate the optimum gain setting, ask the person assisting you to turn the Input GAIN
control clockwise until audio distortion starts to develop. Turn the gain control back
wards slightly to minimize the distortion.
8. If you constantly switch between CD/tape and radio, you will need further adjustment
since radio output level differs from that of CD or tape. In this case, you need to locate a
balanced gain setting which is best for both the output level of radio and the CD.
SYSTEM TUNING (INPUT GAIN ADJUSTMENT)