JL Audio JD 400/4, Руководство пользователя

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6 JL Audio
TURN-ON OPTIONS
The JD400/4 can be switched on and off
using one of three methods, determined by the
position of the amplifier’s “Turn-On Mode”
switch. Please read these options and decide
which is best suited for your specific system.
1) +12V Remote turn-on lead
2) DC Offset-Sensing turn-on circuit
3) Signal-Sensing turn-on circuit
+12V Remote Turn-On: This is the preferred
method for turning the amplifier on/off. The
amplifier will turn on when +12V is present
at its “Remote” input and turn off when +12V
is switched off. This +12V remote turn-on
signal is typically controlled by a source unit
or OEM interface processor’s remote turn-
on wire. The amplifier’s “Remote” turn-on
connector will accept 18 AWG – 12 AWG wire.
To connect the remote turn-on wire to the
amplifier, first back out the set screw on the
top of the terminal block, using the supplied
2.5 mm hex wrench. Strip 1/2 inch (12mm) of
wire and insert the bare wire into the terminal
block, seating it firmly so that no bare wire is
exposed. While holding the wire in the terminal,
tighten the set screw firmly, taking care not to
strip the head of the screw and making sure that
the wire is firmly gripped by the set screw.
If a source unit does not have a dedicated
remote turn-on output, consider one of the
following alternative turn-on options:
These methods are useful when a conventional
+12V remote turn-on signal is not available in a
system. These allow you to operate the amplifier
without having to locate a remote turn-on lead at
the source unit, which can be very useful when
interfacing the amplifier with OEM (factory)
audio systems that do not use conven12V
turn-on leads.
Depending on the characteristics of the audio
signal, one of the following methods may work
better than the other. We recommend trying DC
Offset-Sensing first as it does not require a long
delay to turn the system off after the signal is
shut off.
DC Offset-Sensing: The amplifier will turn on
and off by detecting the presence of a very small
DC signal (offset) that is typical in the audio
output of most OEM (factory) source units and
amplifiers. The amplifier will turn on and off in
reaction to the presence or absence of this DC
offset. The sensitivity of this circuit is designed
for high-level (speaker level) signals, not for low-
level (preamp level) signals. The circuit senses
the input signal from the CH. 1 (L) channel
input only.
Signal-Sensing: The amplifier will turn on
and off by detecting the presence of a full-range
audio signal. After approximately 30 seconds,
the amplifier will shut off. The sensitivity of this
circuit is designed for high-level (speaker level)
signals, not for low-level (preamp level) signals.
The circuit is tuned to react to signals at mid-
range frequencies. This prevents false switching
from signals created by moving loudspeakers
that are in parallel with the amplifier’s input
signal. The circuit senses the input signal from
the CH. 1 (L) channel input only.