Rainbow 271052 Installation Manual - page 30
11
Connection „LOW INPUT“: Preamplifier Input
iPaul DM2000
The output signal of the car radio/CD player is fed by means of a cinch line at the female RCA connector „LOW
INPUT“ (2) right „R“ and left „L“. The input level is regulated by the potentiometer „GAIN“ (12) from 250 mV
(max.) to 7 Volt (min.). The input thus requires the smallest input voltage from 250 mV to right limit(max.) of the
potentiometer „GAIN“.
The RCA jacks (2) for input must always be fed with a right and left signal. Full mono potential is reached only
through simultaneous signal input on both the right and left RCA jacks. The jacks must be provided with a y-RCA
adaptor if only one mono signal is available, e.g., with use over an active crossover switch with only one sub
output.
Note:
Use of different cinch line lengths can result in shifted electrical potentials.The difference in length
forms a ground loop, causing unwanted electric generator disturbances. Do not lay cinch lines in
parallel with electrical lines to avoid distortion couplings.
„REMOTE“: Remote Control
Connect the included 5m black cable with one end of the included remote control and insert the other end of the
cable into the designated socket „REMOTE“ (4) on the amplifier. Phase and volume can now be controlled
remotely with the potentiometers „GAIN“ (18) and „PHASE” (17).
Caution:
The volume “GAIN” (18) on the remote control can be set between the minimum and the set volume
on potentiometer “GAIN” (12) of the amplifier only. It is recommended to set a reasonable basic
volume by potentiometer “GAIN” (12) first and use the remote control for fine tuning afterwards. The
settings remain in effect only as long as theremote control is plugged in. If the remote control is
unplugged, the settings on the potentiometers „GAIN“ (12) and „PHASE“ (13) of the amplifier take
effect. If the remote control is again plugged in, the settings of the remote control once more take
effect.
Loudspeaker Connection
The subwoofers are connected to the connection terminals (1), which are clearly marked „+“ and „–„. Cable ends
should absolutely be equipped with cable end sleeves when connecting. The use of a cable with a minimum
diameter of 4 mm
2
to 10 mm
2
ensures the desired low impedance with the smallest drop in voltage; the good
damping factor of the amplifier remains nearly constant over the entire frequency range. During connection of the
subwoofer to the amplifier it is imperative to make certain that like polarity/phase is connected to like. Mixing up
of polarity/phase will result in loss of bass reproduction through phase cancellation.
Note:
The amplifier can only be operatedas mono; the two connecting terminals are internally switched in
parallel.
Because
of
this,
the
amplifier
cannot
be
operated
in
a
bridge
mode!
Loudspeaker connections may in no case come into contact with the auto body. Failure to comply with
these instructions can result in damage to the amplifier.
In order to prevent falling below the critical minimum level of 1
Ω
, the combined connection impedance of the
subwoofers may not amount to less than 2
Ω
. Because of thermal current load limitations, a 1
Ω
loudspeaker
connection is not permitted. The reason for this is that the output stage is not laid out as "HCC High Current" type
(high current amplifier), which can activate oversize power reserves to very small impedances <0.5
Ω
. The
semiconductors are not sufficient for this application.