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CONTROLS AND INDICATORS
8 • CONTINUOUS ADJUSTMENT OF THE REAR HIGH-PASS AND LOW- PASS
FREQUENCIES: after positioning the filter, either High-Pass or Low-Pass, frequencies can be
adjusted between 30 and 600 Hz.
9 • REAR INPUT GAIN ADJUSTMENT CONTROL: input sensitivity ranges from 200 mV to
4V.
If the amplifier is to be connected to a head unit that is fitted with preamplified RCA outputs,
proceed as follows:
a) set the volume control of your unit to 3/4 of maximum output level;
b) set the input gain control to the point where the maximum sound level with no distortion is
obtained.
10 • REAR INPUT CONNECTORS: connect the pre-output leads of the head unit to the input
connectors of the amplifier. This input will drive the end stage of the REAR section.
11 • SPEAKER CONNECTOR: outputs for speakers connection.
The amplifier allows to connect speakers with minimum 1-ohm impedance per channel in
stereo configuration and with minimum 2-ohm impedance in mono-bridged configuration.
Should the 3-channel configuration be used, total impedance must not exceed the minimum 2-
ohm value. Be sure to keep the right polarity in connecting the speakers. Avoid any contact
between poorly insulated wires and the car’s ground or metal pieces and between the wires
themselves.
12 • FUSE: in case of fuse replacement be sure to use fuses of the same amperage. The use
of fuses with wrong amperage may seriously damage the components of the unit.
13 • BATT + LEAD: connect it directly to the battery positive pole (+) by using a cable with an
adequate section. Place a fuse between the battery and the amplifier so that the fuse is as
close as possible to the battery.
14 • GND CONNECTOR: Do not connect it directly to the battery negative pole (-) but
connect it to a clean part (i.e. paint-free) of the vehicle’s chassis by using a cable with an
adequate section.
15 • REMOTE-ON CONNECTOR: it should be connected to the remote switch-on output lead
or to the output lead of the power antenna coming from the head unit. By doing so the 44.50
can be switched on and off through the head unit.
16 • CHECK CONTROL LED: this led shows the amplifier’s status of operation:
WHITE: the unit is off
GREEN: the unit is working fine
RED: the unit has entered the protection mode
The 44.50 is equipped with three different protection devices:
- Overheating: in case of wrong installation and of amplifier’s overheating, the unit enters the protection
mode before being damaged. As soon as the temperature returns to normal values and mistakes are
corrected, the unit resumes normal operation.
- Overloads: in case a series of speakers is connected to the amplifier with the total impedance value
dropping below a tolerable level, i.e. 1 Ohm, the amplifier enters the protection mode. To restore normal
operation switch off the head unit and then switch it on again.
- Output short circuit: in case of a short circuit at the speaker outlets the unit enters the protection
mode in order to avoid serious damage to the end-stage transistors. Normal operation is resumed by
removing the short circuit and by switching the head unit on again.
O/M 44.50 26/06/02 9:48 Page 3
