Installation - HELIX P TWO Manual

Initial start-up and functions
On: Input stage is bypassed.
Off: Input stage is not bypassed (ex works).
Note: This switch only affects the signal routing of
the Optical Input.
Note: The amplifier must be operated in fullrange
mode for routing the digital input signal directly to

Installation

Connection of HELIX P TWO 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 car radio. It is not mandatory to use both
lowlevel line inputs. If only one channel will be
connected we recommend to use channel A and
set the Input Mode switch to "Mono". When both
channels will be used please choose switch po-
sition "Stereo" or "Stereo Summed", depending
on the application (see page 16, item 11; Input
Mode). The automatic turn-on circuit does not
work when using the lowlevel line inputs (Line
Input) or the digital input (Optical Input). In this
case the remote input (REM) has to be connect-
ed to activate the HELIX P TWO.
Important: It is strictly forbidden to use the
High level and lowlevel Line Input of an individ-
ual channel at the same time as this may cause
severe damage to the lowlevel line outputs of
your car radio. Nevertheless it is possible to
use the Highlevel Input of one channel and the
lowlevel Line Input of another channel simulta-
neously.
2. Connecting the highlevel speaker inputs
The highlevel loudspeaker inputs (Highlevel
Input) can be connected directly to the loud-
18
the power stage. Therefore change the position of
the X-Over switch to „Full" (see page 15, item 7;
X-Over).
Note: If the switch is set to "On" position the High-
level and lowlevel Line Input as well as the Gain
control (4) are without function!
speaker outputs of an OEM or aftermarket radio
using appropriate cables (loudspeaker cables
with 1 mm² / AWG 18 max.).
We recommend the following channel assign-
ment:
Channel A = Left
Channel B = Right
Actually it is not mandatory to use all highlevel
speaker inputs. If one channel will be connect-
ed we recommend to use channel A and set the
Input Mode switch to "Mono". When both chan-
nels will be used please choose switch position
"Stereo" or "Stereo Summed", depending on the
application (see page 16, item 11; Input Mode).
Make sure that the polarity is correct. If one
connection has reversed polarity it may affect
the performance of the amplifier. If this input is
used the remote input (REM) does not need to
be connected as the amplifier will automatically
turn on once a loudspeaker signal is applied.
3. Connecting a digital signal source
If you have a signal source with an optical dig-
ital output you can connect it to the amplifier
using the appropriate input.
The automatic turn-on circuit does not work
when the digital input is used. Therefore it is
mandatory to connect the remote input (REM).
Due to the fact that the Optical Input always
provides a stereo signal, the Input Mode switch
has to be set to "Stereo" or "Stereo Summed",
depending on the application (see page 16,
item 11; Input Mode).
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 TWO. This may cause severe damage to