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4.3 Description of features and controls
4.3.1 Line input - INPUT
With the signal input RCA jacks, left („L“ ch1 or ch3) and right („R“ ch2 or ch4) input channels
can be connected to the amplifier. Please use high performance audio cable like Signat
Platinum series!
4.3.2 Gain - GAIN
The input level (sensitivity) of the amplifier can be adjusted to the output voltage of your head
unit using the input level control. The input level control does not adjust volume! Optimum
setting of the control gives you a sufficiently large regulating zone for your car stereo
combination without any distortion or overloading.
The „GAIN“ control allows an adjustment from 4.0V to 150mV. Turn clockwise to increase
input sensitivity, turn counterclockwise to decrease.
To adjust the input sensitivity, turn the controls fully counterclockwise to minimum. Adjust the
car radio unit volume to maximum volume, and then turn the level controls on the amplifier
clockwise until audible distortion occurs. Now turn very slightly counterclockwise and the
adjustment is done.
An incorrect level control adjustment not only has a negative effect on "sound impression" but
can also destroy your speakers!
4.3.3 ENS noise suppression - ENS
The ENS adjustment capability allows you to fine-tune the BIC’s (Balanced Input Circuitry) for
maximum noise rejection of your car audio system.
It is usually not necessary to change the factory ENS setting.
Therefore we recommend using the factory setting of ENS as it is.
In case of any trouble with whining or and ticking noise problems, we recommend consulting
an experienced installation specialist for assistance in ENS adjustment.
CAUTION: the amplifier must be installed correctly, and connected to the source and
any other components normally used in the system. Never insert anything metallic into
any openings in the Amplifier side panels. For ENS adjustment, only use a small, non-
metallic, blade type screwdriver that will fit though the opening.
Recommended adjustment of ENS:
1. With the system turned off, disconnect the main speakers from the channel you are going
to fine tune
2. Mark the position(s) of the „GAIN“ control(s) for the channel(s) you are going to fine tune.
3. Turn the „GAIN“ control(s) fully CW for the channel(s) you are going to fine tune.
4. Connect a small test speaker to the channel you want to adjust.
5. Make sure the source unit volume is fully CCW (min).
6. Start the engine, and turn on the system
7. Use a small plastic screwdriver to adjust ENS for the channels the test speaker is
connected to. Listen to the speaker, and adjust for the minimum noise level.
8. Adjust the „GAIN“ control(s) to the marked (original) position again, disconnect the test
speaker and reconnect the original speaker(s).
9. Repeat steps 1 to 8 for any other channel(s) you wish to fine tune.
4.3.4 Bass boost - BASS BOOST
The switch marked ‘BASS BOOST’ allows for a reinforcement of the bass reproduction at a
frequency of 50Hz.