JL Audio NexD RD1500/1, Руководство пользователя

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7
INPUT SECTION
The RD1500/1 employs a differential-balanced
input topology that provides the user with a
high degree of input flexibility, while retaining
superior noise rejection. This type of circuit
also allows the RD1500/1 to accept high-voltage
inputs from factory source unit outputs without
excessive distortion or noise problems.
You may run a stereo or a mono signal into
the inputs of the amplifier. The amplifier’s input
section automatically sums stereo signals to mono
for the internal amplifier section. The amplifier
will operate with only one input connection but
will require an increase in input sensitivity to
overcome the loss of signal. If a single mono input
signal is used, you may use a “Y-adaptor” to split
the mono signal into both inputs of the amplifier.
If you are feeding only one input and using either
the DC-Offset or Signal Sensing “Turn-On
Mode”, you must use the left-channel input for
the automatic turn-on to operate.
INPUT VOLTAGE RANGE
A wide range of signal input voltages
can be accommodated by the RD1500/1’s
input section (200mV – 8V). This wide
range is split up into two sub-ranges,
accessible via the “Input Voltage” switch:
“Low”: for preamp level signals
“High”: for speaker level signals
The “Low” position on the “Input Voltage”
switch selects an input sensitivity range
between 200mV and 2V. This means that the
“Input Sensitivity” rotary control will operate
within that voltage window. If you are using
an aftermarket source unit, with conventional
preamp level outputs, this is the position you
should select.
The “High” position on the “Input Voltage”
switch selects an input sensitivity range between
800mV and 8V for all input channels. This is useful
for certain high-output preamp level signals as well
as speaker-level output from source units and small
amplifiers. To use speaker-level sources, splice the
speaker output wires of the source unit or small
amplifier onto a pair of RCA cables or plugs or use
the JL Audio ECS Speaker Wire to RCA adaptor
(XD-CLRAIC2-SW).
Line output converters are usually not needed
with the RD1500/1. If you find that the output
cannot be reduced sufficiently with a direct
speaker level signal applied to the amplifier and the
“Input Voltage” switch in its “High” position, you
may use a line output converter (like the LoC™ 22)
or voltage divider to reduce the signal level.
INPUT SENSITIVITY CONTROLS
The control labeled “Input Sensitivity” and
“Clipping” LED are used to match the source
unit’s output voltage to the input stage of the
RD1500/1 for maximum clean output. Rotating
the control clockwise will result in higher
sensitivity (louder for a given input voltage).
Rotating the control counter-clockwise will
result in lower sensitivity (quieter for a given
input voltage).
To properly set the amplifier for maximum
clean output, please refer to Appendix A (page
12) in this manual. After using this procedure,
you can then adjust the “Input Sensitivity”
levels downward if this is required to achieve the
desired system balance.
Do not increase any “Input Sensitivity”
setting for any channel(s) of any amplifier in the
system beyond the maximum level established
during the procedure outlined in Appendix
A (page 12). Doing so will result in audible
distortion and possible speaker damage.