Connection Examples; Subwoofer Connection - Blaupunkt GTA 470 DSP Mode D'emploi

Audio inputs
The preamplifi er outputs are connected to the cinch (RCA)
sockets via a shielded audio line (see Fig. 3).
Plus / minus connection
– We recommend a minimum cross section of 6 mm
– Route commercially available plus cables to the battery
and connect via fuse holder.
– Use cable glands for holes with sharp edges.
– Securely fasten commercially available minus cables to a
noise-free earth point (chassis screw, chassis metal) (not
to the minus pole of the battery).
– Scrap the contact surfaces of the earth point until they
are bright and grease with graphite grease.
Integrated fuses (2 x 20 A)
The fuses integrated in the amplifi er protect the power
amplifi er and the entire electrical system in case of an error.
If a replacement fuse is used, never bridge fuses or replace
them with a type with higher current.

Connection examples

Connection of the voltage supply ..................................Fig. 2
Audio inputs ...........................................................................Fig. 3
Loudspeaker connections .................................................Fig. 4 - 8
Remote control connection (optional equipment) ......Fig. 9
+12V
Remote connection of the amplifi er with switchable +12 V
voltage source.
This allows the amplifi er to be switched on and off using the
on/off -switch of the car sound system.
Loudspeaker connections
(If the amplifi er is to be jumpered, continue with the section
"Bridged loudspeaker connections" at this point).
As with every audio component, the correct polarisation of
amplifi er and loudspeakers is of essentially importance for a
good bass response. For this reason, ensure that the positive
connection (+) of the amplifi er is connected with the posi-
tive connection (+) of the loudspeaker; the same applies to
the negative connections (-). In addition, the left amplifi er
channel must be connected with the left loudspeaker and
the right amplifi er channel with the right loudspeaker.
Bridged loudspeaker connections
The GTA amplifi er can also be bridged for a mono confi gura-
tion. This allows the amplifi er to be used for one or several
subwoofers or a mid-range driver. In this confi guration, the
amplifi er combines the right and left channel to a single-
channel output (mono output).
Note:
The amplifi er can add the right and left signal information
only if the right as well as the left cinch (RCA) connection
were carried out.
Caution:
In a bridge circuit, the amplifi er load must be 4 Ω or
higher. A lower load leads to an overheating or switch-
off of the amplifi er and can cause permanent damages.
GTA_470_DSP_13LG.indd 7 GTA_470_DSP_13LG.indd 7

Subwoofer connection

The GTA 470 DSP features three diff erent options of con-
necting a subwoofer:
– An active subwoofer or an additional amplifi er are con-
nected with a cinch (RCA) cable to the two SUBWOOFER
2 .
OUTPUT sockets (see Fig. 7). The setting options of the
integrated DSP (Digital Sound Processor) can be used
in this case.
– A passive subwoofer is connected to the bridged loud-
speaker output (see the section "Bridged loudspeaker
connections"). To be able to use the setting options of
the integrated DSP (Digital Sound Processor), the two
REAR INPUT sockets must additionally be connected with
a commercially available cinch (RCA) cable with the two
SUBWOOFER OUTPUT sockets (see Fig. 8).
– A passive subwoofer is connected to the bridged loud-
speaker output (see the section "Bridged loudspeaker
connections"). The setting options of the integrated DSP
(Digital Sound Processor) cannot be used in this case.
DSP sound settings
(FRONT and REAR loudspeakers)
A variety of options is available to optimise the sound of the
connected loudspeakers:
– GAIN control (FRONT and REAR)
The GAIN control is used to adjust the input sensitivity
of the power amplifi er to the output voltage of your car
sound system preamplifier output. The GTA 470 DSP
features separate controls for the FRONT and REAR loud-
speakers. In each case, the adjustment range is from 0.2 V
to 5 V. If a car sound system of a third party manufacturer
is connected, the input sensitivity must be adjusted cor-
responding to the manufacturer data.
A few important explanations in this context:
By turning the GAIN control clockwise, the input sensitivity
of the amplifi er and, therefore, also the volume increases.
However, this is not a volume control. In the end position,
it is not possible to achieve a higher amplifi er output, even
if it sounds like that at fi rst. The system merely increases
the volume faster if the volume control of the car sound
system is turned up.
– FULL/HI/LOW switch and X-OVER control
(FRONT and REAR)
For the GTA 470 DSP, the type of frequency crossover
("Low-Pass" or "High-Pass") and the desired cut-off fre-
quency can be adjusted separately for the FRONT and
REAR loudspeakers. Select the cut-off frequency up to
which lower frequencies (high-pass) or higher frequencies
(low-pass) should be blocked. Only frequencies above
the cut-off frequency (high-pass) or below the cut-off
frequency (low-pass) are passed on to the loudspeakers.
The cut-off frequency is dependent upon the frequency
range of the loudspeakers (see recommended frequency
range of the loudspeakers).
"High-Pass" (switch setting: HI)
With a setting of 80 Hz, the amplifi er has a frequency range
from 80 Hz to 30,000 Hz.
"Low-Pass" (switch setting: LOW)
This control is active if the switch is in the LOW position,
and allows for setting the desired entry frequency.
GTA 470 DSP
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