6.2.2 Bridge operation for a subwoofer
If a mono subwoofer is to be driven in bridge op-
eration, use one of the two following possibilities
of connection:
1 . If the car radio is equipped with outputs for a
subwoofer amplifier, connect them to the two
jacks INPUT (2) .
2 . For car radios without subwoofer output, con-
nect the line outputs for the left channel and
right channel separately to the two jacks INPUT,
as shown in fig . 3 .
6.3 Line outputs
If a second power amplifier is used in the car
HiFi system, the inputs of this amplifier can be
connected to the jacks OUTPUT (1) [see fig . 5]
to implement e . g . a 2-way active system with
mid-high range speakers and bass speakers or
a subwoofer . At these outputs, the same signal
is available which is fed to the jacks INPUT (2) .
6.4 Speakers
It is possible to use full range speakers (2-way or
3-way speakers), mid-high range speakers, bass
speakers, or a subwoofer . In 2-channel operation,
the power amplifier can drive the speakers for
the left channel and right channel or, in bridge
operation with increased output power, it can
drive the speaker for one channel or a subwoofer .
Important! All speakers must be connected
with 2 poles, i . e . without common ground
connection . When choos ing suitable speakers,
pay attention to their mechanical and electrical
capability in con nection with the power used
of the power amplifier (also see specifications) .
6.4.1 2-channel operation
The highest output power is reached when con-
necting 2 Ω speakers or a speaker group with a
total impedance of 2 Ω per channel (e . g . two 4 Ω
speakers connected in parallel) . However, it is also
possible to connect individual 4 Ω speakers; in this
case, the output power is slightly reduced . Con-
nect the speakers to the terminals SPEAKER (15)
– also see fig . 3:
L+ = positive pole left speaker
L− = negative pole left speaker
R+ = positive pole right speaker
R− = negative pole right speaker
6.4.2 Bridge operation
In bridge operation, the impedance of the con-
nected speaker or the total impedance of a
speaker group must not fall below 4 Ω! Connect
the speaker to the terminals SPEAKER (15) . Pay
attention to the lettering BRIDGE – also see fig . 4:
L+ = positive pole
L− = remains unconnected
R+ = remains unconnected pole
R− = negative pole
7 Setting into Operation
Important! Prior to the first switching-on,
select the filter with the switch CROSSOVER
(7) and coarsely adjust the crossover frequency
(chapter 7 .1) so that the speakers will not be
overloaded by a frequency range that might
be too wide . It is also recommended to check
first once again if the entire wiring of the car
HiFi power amplifier is correct, and only then to
connect the negative terminal of the car battery .
For most applications, the switch OUTPUT (8)
must be set to the position STEREO . Only if the
power amplifier is to drive two speakers for the
right channel or the left channel and only one
jack INPUT RIGHT or LEFT (2) is connected, set
the switch to MONO .
7.1 Selecting the filter and adjusting
the crossover frequency
Depending on the speaker type connected, select
the filter with the switch CROSSOVER (7) .
For full range speakers, set the switch to the
left stop to position FULL . The power amplifier
reproduces the entire frequency range .
For bass speakers or a subwoofer, set the switch
to position LP . The low pass is switched on and
the medium and high frequencies are suppressed .
For the time being, coarsely adjust the crossover
frequency with the control LP (6) .*
For mid-high range speakers, set the switch to
position HP . The high pass is switched on and the
low frequencies are thus suppressed . For the time
being, coarsely adjust the crossover frequency
with the control HP (5) .*
* For a guidance, observe the frequency range of the
speakers used . The fine adjustment is made with cor-
responding meters after the level adjustment .
7.2 Adjusting the level and
the bass boosting
Hint To keep the interference by the electric
system of the car as low as possible, the output
level of the signal source should be 1 .5 V as a
minimum .
1) Turn the control LEVEL (3) to the left stop to
position MIN .
2) Switch on the car HiFi system completely . The
green POWER LED (13) lights up . However, the
power amplifier is muted for approx . 3 seconds
(switch-on delay) .
3) Adjust the signal source, e . g . the car radio, to
the maximum, non-distorting volume .
4) Turn up the control LEVEL (3) to the non-
distorting maximum .
5) If required, the bass frequencies can be
boosted with the control BASS EQ (4) [max .
12 dB / 50 Hz] .
6) If further power amplifiers are used in the car
HiFi system, reduce the levels of the channels
which are too high to match the volumes of
all channels with each other .
Specifications
Output power
Total power (P
)
max
2-channel operation with 2 Ω speakers
2-channel operation with 4 Ω speakers
Bridge operation with 4 Ω speakers
Frequency range
Minimum speaker impedance
2-channel operation
Bridge operation
Inputs
Channel separation
S / N ratio
THD
Low pass
High pass
Bass boosting
Power supply
Admissible ambient temperature
Dimensions (W × H × D), weight
All rights reserved by MONACOR
be reproduced in any form or by any means for any commercial use.
8 Troubleshooting
If there is no sound after switching on the car HiFi
system, locate the fault more precisely by means
of the two LEDs POWER (13) and PROT . (14) .
The LED POWER does not light up
1) Check the fuses (12) of the car HiFi power
amplifier HPB-602:
HPB-602: 1 × 30 A
HPB-1502: 2 × 30 A
and the additional fuse at the car battery
HPB-602: 30 A
HPB-1502: 60 A
Replace defective fuses . Only use fuses with
the indicated values . Never insert a fuse of a
higher value . The power amplifier may be dam-
aged and the warranty will be void .
2) Check the 12 V power supply cable and the
ground cable for correct connection and for
interruptions .
3) Check at the terminal REM (10) of the power
amplifier if +12 V is available . If not, remove
the cable at the terminal REM and temporarily
bridge the terminals REM and "+12V" (11) . If
the power amplifier switches on now, the fault
is due to the missing control voltage . Check the
12 V control output of the car radio and the
corresponding connection cable to the power
amplifier .
The LED POWER lights up
1) Check the cables with RCA connectors from
the signal source to the car HiFi power ampli-
fier . Are the plugs correctly connected? Are the
cables interrupted?
2) Check the signal source . Is the signal source
switched on? Have the correct outputs been
used? Is the signal source defective?
3) Check the speaker cables for interruptions .
4) Check the connected speakers .
LED PROT. lights up
The power amplifier is protected with a protective
circuit against short circuit at the speaker outputs
and against overheating . If the protective circuit
is activated, the LED PROT . (14) lights up . In case
of overheating, the power amplifier automatically
switches on again after cooling down . In case of
a short circuit at the speaker outputs, after elim-
inating the error, the 12 V control voltage must
shortly be switched off (e . g . switch off the car
radio) to reset the protective circuit .
HPB-602
350 W
2 × 100 W RMS
2 × 70 W RMS
1 × 225 W RMS
20 Hz – 20 kHz
2 Ω
4 Ω
0 .4 – 4 V/20 kΩ, RCA
> 45 dB
> 94 dB (weighted)
< 0 .2 %
40 – 300 Hz, 6 dB / octave
40 – 500 Hz, 6 dB / octave
0 – 12 dB / 50 Hz
10 – 16 V (⎓), 22 A
0 – 40 °C
252 × 62 × 243 mm, 1 .9 kg
®
INTERNATIONAL GmbH & Co. KG. No part of this instruction manual may
Subject to technical modification .
HPB-1502
750 W
2 × 250 W RMS
2 × 175 W RMS
1 × 500 W RMS
20 Hz – 20 kHz
2 Ω
4 Ω
0 .4 – 4 V/20 kΩ, RCA
> 50 dB
> 89 dB (weighted)
< 0 .2 %
40 – 300 Hz, 6 dB / octave
40 – 500 Hz, 6 dB / octave
0 – 12 dB / 50 Hz
10 – 16 V (⎓), 45 A
0 – 40 °C
252 × 62 × 363 mm, 3 kg
7