Installation - HELIX P ONE Manual

Installation

Connection of HELIX P ONE to the head unit /
car radio:
Caution: Carrying out the following steps will re-
quire special tools and technical knowledge. In or-
der to avoid connection mistakes and / or damage,
ask your dealer for assistance if you have any ques-
tions and follow all instructions in this manual (see
page 13). It is recommended that this unit will be
installed by an authorized HELIX dealer.
1. Connecting the lowlevel line inputs
Use the correct cable (RCA / Cinch cable) to
connect these inputs to the lowlevel line outputs
of your head unit / car radio. It is not mandato-
ry to use both lowlevel line inputs. If only one
channel will be connected use channel A and
set the Input Mode switch to "MONO".
When both channels will be used please choose
switch position "STEREO" (see page 15, item 5;
Input Mode switch).
2. Connecting a digital signal source
If you have installed the HELIX Digital Input
Module HDM 1 and have a signal source with
an optical digital output you can connect it di-
rectly to the amplifier using the appropriate in-
put.
Important: The signal of a digital audio source
normally does not contain any information
about the volume level. Keep in mind that this
will lead to full level on the outputs of the HELIX
P ONE. This may cause severe damage to your
speakers. We strongly recommend to only use
volume controlled audio sources!
Information: The P ONE can only handle un-
compressed digital stereo signals in PCM for-
mat with a sample rate between 28 kHz and
96 kHz and no MP3- or Dolby-coded signals.
3. Configuration of the digital signal input
If you have installed the HELIX Digital Input
Module HDM 1 and connected a digital signal
source you have the possibility to route the dig-
ital signal directly and loss-free from the inte-
grated DA converter to the internal power am-
plifier. To activate the direct signal routing you
have to change the position of the SPDIF Direct
In switch to "On" (see page 15, item 8).
Note: This switch only affects the signal routing
of the optical input.
4. Adjustment of the input sensitivity
If you want to change the input sensitivity use
the Gain control (see page 15, item 4; Gain).
Attention: It is mandatory to properly adapt
the input sensitivity of the P ONE to the
signal source in order to avoid damage to
the amplifier.
5. Connection to power supply
Make sure to disconnect the battery before
installing the HELIX P 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 (P ONE = max. 120 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.
6. Adjustment of the filters in the upstream
signal processor
If the P ONE is driven by a digital signal pro-
cessor (DSP) we strongly recommend for best
audio performance to provide a subsonic (high-
pass) filter with a cut-off frequency of 20 Hz and
a slope of 24dB per octave (Butterworth charac-
teristic) in the signal path.
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