19
Installation
Connection of HELIX DSP.3 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 15). It is recommended that the device will be
installed by an authorized HELIX dealer.
1. Connecting the pre-amplifier inputs
Use the correct cable (RCA / cinch cable) to
connect these inputs to the pre-amplifier /
lowlev el / cinch outputs of your head unit / car
radio. Each input can be assigned to any output
using the DSP PC-Tool software. The automat-
ic turn-on circuit does not work when using the
pre-amplifier inputs. In this case the remote in
-
put has to be connected to activate the HELIX
DSP.3.
Important:
It is strictly forbidden to use the
Highlevel
and lowlevel
Line Input
of an indi-
vidual channel at the same time as this may
cause severe damage to the lowlevel line out
-
puts of your head unit / car radio. Nevertheless
it is possible to use the
Highlevel Input
of one
channel and the lowlevel
Line Input
of another
channel simultaneously.
2. Connecting the highlevel speaker inputs
The highlevel loudspeaker inputs can be con
-
nected directly to the loudspeaker outputs of an
OEM or aftermarket radio using appropriate ca-
bles (loudspeaker cables with 1 mm² / AWG 18
max.).
We recommend the following channel assign-
ment if a common car radio will be connected to
the signal processor:
Channel A = Front left
Channel B = Front right
Channel C = Rear left
Channel D = Rear right
Actually it is not mandatory to use all high level
speaker inputs. If only two channels will be con-
nected we recommend to use the channels A
and B. Make sure that the polarity is correct. If
one or more connections have reversed polar
-
ity it may affect the performance of the signal
processor. If this input is used the remote input
does not need to be connected as the signal
processor will automatically turn on once a
loudspeaker signal is received.
3. Connecting a digital signal source
If you have a signal source with an optical digi-
tal output you can connect it to the signal pro-
cessor using the appropriate input. In standard
configuration the HELIX DSP.3 automatically
activates the used digital input if a digital audio
signal is detected. This function can be deac-
tivated via the DSP PC-Tool software. Alterna
-
tively you can manually activate the digital input
if you are using the optional remote control. The
automatic turn-on circuit does not work when
the digital input is used. Therefore it is manda-
tory to connect the remote input of the
Power
Input
. Please note that it is possible to connect
a source to the digital input and the
Highlevel
Input
or the
Line Input
at the same time.
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
DSP.3 and your connected amplifiers. This may
cause severe damage to your speakers. We
strongly recommend to use an optional remote
control for adjusting the volume level of the dig
-
ital signal input!
Information:
The HELIX DSP.3 can only han-
dle uncompressed digital stereo signals in PCM
format with a sample rate between 12 kHz and
96 kHz and no MP3- or Dolby-coded digital
audio stream!
4. Adjustment of the input sensitivity
Attention:
It is mandatory to properly adapt
the input sensitivity of the DSP.3 to the
signal source in order to avoid damage to
the signal processor.
If you want to change the input sensitivity use
the control 3 (see page 17, item 3;
Input Sensi
tivity
). The ex works setting of the input sensitiv
-
ity is the maximum counter-clockwise position.
This is definitely the best setting for most appli
-
cations. Only if the head unit / car radio doesn´t
deliver enough output level, the input sensitivity
should be increased by the turning the control
