HELIX C ONE Manual page 23

In switch to "On" (see page 19, item 2) as well
as the position of the X-Over switch to "FULL"
(see page 21, item 23).
Note: This switch only affects the signal routing
of the optical input.
4. Adjustment of the input sensitivity
Attention: It is mandatory to properly adapt
the input sensitivity of the C ONE to the sig-
nal source in order to avoid damage to the
amplifier.
If you want to change the input sensitivity use
the Level control (see page 20, item 16; Level
control).
5. Connection to power supply
Make sure to disconnect the battery before
installing the HELIX C ONE!
Connect the +12 V power cable to the positive
terminal of the battery. The positive wire from
the battery to the amplifier power terminals
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 (C ONE = max. 90 A RMS at
12 V power supply). If your power wires are
short (less than 1 m / 40") then a wire gauge
of 16 mm² / AWG 6 will be sufficient. In all other
cases we strongly recommend gauges of 25 -
35 mm² / AWG 4 – 2!
The ground cable (same gauge as the +12 V
wire) should be connected to a common ground
reference point (this is located where the neg-
ative terminal of the battery is grounded to the
metal body of the vehicle), or to a prepared met-
al location on the vehicle chassis, i.e. an area
which has been cleaned of all paint residues.
Unique Features of the HELIX C ONE
Start-Stop capability
The switched power supply of the HELIX C ONE
assures operation even if the battery's voltage
drops down to 6 Volts during engine crank.
6. Connecting the remote input
The remote input (REM) has to be connected to
the radio remote output. This is only activated
if the head unit / car radio is switched on. Thus
the amplifier is switched on and off together with
the head unit / car radio.
We do not recommend controlling the remote
input via the ignition switch to avoid pop noise
during turn on / off.
If an additional digital signal processor (DSP)
is installed in the signal path between the radio
and the amplifier, the remote output of the DSP
must be used to turn on the C ONE.
7. Connecting the loudspeaker outputs
The loudspeaker outputs can be connected
directly to the wires of the loudspeakers. Never
connect any of the loudspeaker cables to the
chassis ground as this will damage your ampli-
fier and your speakers.
Ensure that the loudspeakers are identical and
corrctly connected (in phase), i.e. plus to plus
and minus to minus. Exchanging plus and mi-
nus causes a total loss of bass reproduction.
The positive terminal is indicated on most
speakers. The impedance must not be less
than 1 Ohm (2 Ohms in TwinPower Link mode),
otherwise the amplifier protection will be acti-
vated. Examples for speaker configurations can
be found on page 24 et sqq.
High-Resolution audio
The extremely broadband audio bandwidth of the
amplifier ensures a lossless audio reproduction of
High-Resolution audio content to provide the best
possible sound in studio quality.
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