Crunch GTO1200, User Manual, Page: 10 / 32

10
ENG
+
-
blue = speaker - right - positive
-
+
white = speaker - right - negative
orange = speaker - left - negative
yellow = speaker - left - positive
The subsonic filter is suited to filter the lower frequencies out from the audio signal to avoid unwanted
hum noises from the subwoofer. Set the desired crossover frequency of the subsonic filter by using
the controller (SUBSONIC, Fig. 1, 7). Thus to that only the frequencies above the chosen crossover
frequency will be amplified and the subwoofer plays more precised and efficient.
VARIABLE SUBSONIC FILTER
SUBWOOFER CONNECTIONS
- The total loudspeaker impedance must not be lower than 1 ohm.
- Never connect loudspeaker cables with the ground of the chassis or the +12 V supply voltage.
- If the amplifier is operated with a too low impedance or incorrectly used, the entire sound system
may be damaged. This means a warranty void in such cases.
OPERATING ELEMENTS
Turn the input level control (INPUT LEVEL, Fig. 1, 3) on the amplifier to the MIN. position. Turn then
the volume control of the headunit to 80% - 90% of its maximum volume. Now turn slowly the input
level control on the amplifier (INPUT LEVEL, Fig. 1, 3) in a clockwise direction until you hear some
distortion, then turn back slightly until the distortion is not audible anymore.
INPUT SENSITIVITY
The HIGH LEVEL INPUT (Fig. 1, 2) is suitable to connect the amplifier inputs with speaker wires, if
your headunit is not equipped with pre-amplifier RCA outputs. Extend therefore every regarding speaker
cable from your headunit with appropriate speaker cables from your car audio retailer to the mounting
location of the amplifier. Then connect the each matching loudspeaker cable with the cables of the
included HIGH LEVEL INPUT jack like described below.
NOTE: Never use the HIGH LEVEL INPUT and the RCA inputs at the same time. This may damage
the amplifier seriously. The loudspeaker cables of the HIGH LEVEL INPUT must have no contact to the
ground (GND).
HIGH LEVEL INPUT
The amplifier detects a voltage rise (6 Volts) with a so called ”DC Offset” over the connected input
signal on the HIGH LEVEL INPUT (Fig. 1, 2) when the headunit will be switched on. Hence, the amplifier
will also be turned on. As soon as the headunit will be turned off, the amplifier turns also automatically
off. In this case the turn-on connection (REM, Fig. 2, 2) is not needed.
Note: The Auto Turn On function usually works with 90% of all headunits, because they are equipped
with ”High Power”-outputs. Only with a few older and still existing headunits the Auto Turn On function
is not working.
AUTO TURN ON
Set the desired cross-over frequency by using the controller (LPF, Fig. 1, 8). Thus to that only the
frequencies below the chosen cross-over frequency will be amplified and the subwoofer plays more
precised and efficient.
VARIABLE LOWPASS FILTER