MAC Audio APM 4.0 Mode D'emploi page 9

3. iMPortAnt instAllAtion inforMAtion
· This appliance may only be connected to a 12 volt system with negative ground.
· The heat radiated when the amplifier is used means that sufficient air circulation is required at the place of installation. It is very
important that the cooler's cooler ribs do not contact any metal plating or any surfaces which could impair air circulation. The
amplifier may not be installed in small confined spaces or spaces without air circulation (e.g. spare wheel recess or under the vehicle
carpeting). Installation in the boot is recommended.
· Install the amplifier in such a way that it is protected as far as possible against vibrations and dust and dirt.
· Make sure that the input/output cables are sufficiently distant from the power supply cables as otherwise interference may occur.
· Make sure that the fuse and operating elements are accessible after installation.
· The appliance's reliability and performance depend on the quality of installation. Preferably get an expert to install the system,
particularly if you want to install several loudspeakers or a complex multi-way system.
4. ConneCtions
4.1 Power suPPlY And AutoMAtiC switChing on
important notice: Before commencing the installation, disconnect the plus terminals from the car battery in order to prevent
short circuits.
The power cabling usually installed in on-board car networks is not sufficient for a power amplifier's demands. Make sure that the power
lines to GND and to the +12 V terminal have been sufficiently specified. A cable cross-section of at least 8 mm² must be used to connect
the battery to the amplifier's terminals.
First connect the amplifier's GND terminal to the battery's minus pole. It is very important that the connection is good. Dirt residues must
be carefully removed from the battery's connection point. A loose connection may cause malfunctions or interference noise or distortion.
The +12 V amplifier connection must then be connected with a power cable possessing an integrated fuse to the battery's plus pole. The
fuse should be located close to the battery; for safety reasons, the cable from the positive terminal of the battery to the fuse must not
exceed 60 cm in length. Only insert the fuse when all installation work, including the connection of the loudspeakers, has been completed.
Now connect the car hi-fi receiver's remote control connection to the amplifier's REM control jack. A cable with a cross-section of 0.75 mm²
is sufficient for connecting the amplifier's REMOTE connection and the control device.
4.2 ConneCting to A CAr rAdio with CinCh outPuts
Use the „ INPUT " low-level inputs when connecting a car radio with low level outputs (cinch jacks).
When installing the audio cable between the cinch output of your car receiver and the cinch input of the amplifier inside your car, the
audio and power supply cables should, wherever possible, not be routed along the same side of the vehicle. We recommend an isolated
installation, e.g. routing the power cable through the cable duct on the left-hand side and the audio cable through the cable duct on the
right-hand side or vice versa. This reduces interference due to crosstalk into the audio cables.
4.3 ConneCting to A CAr rAdio without CinCh outPuts
When connecting a car radio without low-level cinch outputs (cinch jacks), use the supplied adapter to connect the car radio amplifier's
final stages to the amplifier's high-level input marked with HI INPUT. Make sure that the correct poles are used for the connections as
otherwise the amplifier may be damaged.
important notice: Never connect the car radio to the low-level AND the high-level inputs simultaneously (HI INPUT and INPUT). Either use
the low-level OR the high-level input. If your car radio possesses low-level outputs, these should preferably be used due to the improved
tonal response and interference voltage distance.
4.4 loudsPeAKer ConneCtions
· In normal operating mode (i.e. one loudspeaker on each individual amplifier channel), the lowest terminal resistance is 2 ohm per
channel.
· In bridging mode (two amplifier outputs combined) the lowest terminal resistance doubles to 4 ohm.
· The impedance in tri-mode may not fall below 2 ohm per channel.
· Never connect the loudspeakers' minus terminals to the vehicle chassis.
· Never connect the +12 V supply voltage to a loudspeaker output as this would destroy the amplifier final stage.
If the amplifier is operated with lower terminal resistances or incorrectly used as described above, both the amplifier and the
loudspeakers may be damaged. The warranty becomes void in such cases.
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