MTX Audio 801D - Manual (Page 6)

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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 amplifi er. The output voltage of individual source units
can vary. Some source units have an output of 200mV and others have 5 volts or more. To
cater to these variations, the amplifi er has an adjustable gain level that ranges from 100mV to
5 volts. Follow the steps below to set gains.
Besides better sonic reproduction, proper input gain also helps to prolong the reliability span
of your amplifi er by eliminating excessive internal temperature generated by incompatible
source unit output and amplifi er 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
reconnecting 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 amplifi er.
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 (fl at).
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 headunit.
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)
Note: If you are using the Remote Gain, make sure to take this into account during setup
procedures of the subwoofer amplifi er. You should set the system up with the Remote Gain
plugged in and with the level knob turned all the way down (counter-clockwise). The
Remote Gain only works when you’ve selected the LP (low-pass) crossover
confi guration.
CROSSOVER SELECTION
The amplifi er has built-in high-pass/low-pass fi lters that can be bypassed by sliding the
switch to the (FR) position.
1. When the high-pass is selected (HP), the amplifi er will be devoted to mid/tweeters.
2. When the low-pass is selected (LP), the amplifi er will be used to drive woofers/subwoofers.
With this setting, the Remote Gain can directly control the amplifi er playback level.
3. When the full range is selected (FR), the amplifi er is used as a full range amplifi er.
CROSSOVER FREQUENCY SELECTION (FREQ)
Both the high-pass and the low-pass section offer continuously adjustable crossover
frequencies between 40Hz and 350Hz. Adjust the setting according to your speaker
component specifi cation or to your particular preference.
BASS BOOST CONTROl (BASS BOOST)
Select a boost level between 0dB and +18dB @ 40Hz to enhance the bass performance for
your sound system. BASS BOOST is NOT free! Every 3dB of boost costs you twice as much in
power. Make sure to set the fi nal gains after setting the Bass Boost to work best with your
subwoofer/enclosure combination. More is NOT always better!
SYSTEM TUNING (CROSSOVER ADJUSTMENT)
L+R+
L- R-
SPKR
INPUT