HELIX U 8A Manual page 15

Important: It is strictly forbidden to use the High-
level Input and lowlevel Line Input at the same time.
This may cause severe damage to the lowlevel line
outputs of your car radio.
9 Line Input
2-channel lowlevel line input to connect signal
sourc es such as head units / radios / DSPs.
Important: It is strictly forbidden to use the High-
level Input and lowlevel Line Input at the same time.
This may cause severe damage to the lowlevel line
outputs of your head unit / car radio.
Fuse
10
The input fuse is connected in parallel and provide
protection against an internal fault of the device,
therefore the system must be additionally protect-
ed by a further main fuse located close to the bat-
tery (max. distance from battery: 30 cm / 12"). The
HELIX U 8A / U 10A is equipped with a 25 Ampere
fuse.
Power Input
11
This input is used for connecting the active sub-
woofer to the power supply of the vehicle and for
the remote input.
+12 V: The +12 V supply cable must be connected
to the positive terminal of the battery. The
positive wire from the battery to the pow-
er terminal of the active subwoofer needs
to have an inline fuse at a distance of less
than 12 inches (30 cm) from the battery.
The value of the fuse is calculated from the
maximum total current draw of the whole
car audio system. If your power wires are
short (less than 1 m / 40") then a wire gauge
of 4 mm² / AWG 12 will be sufficient. In all
other cases we recommend a cross section
6 mm² / AWG 10!
GND: The ground cable (same gauge as the
+12 V wire) should be connected to a com-
mon ground reference point (this is located
where the negative terminal of the battery is
grounded to the metal body of the vehicle),
or to a prepared metal location on the ve-
hicle chassis, i.e. an area which has been
cleaned of all paint residues.
REM: The remote lead should be connected to the
remote output / automatic antenna (aerial
positive) output of the head unit / car ra-
dio. This is only activated if the head unit is
switched on. Thus the active subwoofer is
switched on and off together with the head
unit / car radio. This input needn't to be as-
signed if the Highlevel Input is used.
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