JL Audio JX360/4 Owner's Manual page 5

Input sensItIvItY controls
The controls labeled "Input Sens." located in
each channel pair's control section can be used
to match the source unit's output voltage to the
input stage of each pair of amplifier channels
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 any or all "Input Sens."
levels downward if this is required to achieve the
desired system balance.
!
I m p o r ta n t !
Do not increase any "Input Sens." 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.
8
FIlter controls
The active filter built into each channel
section of the JX360/4 can be used to eliminate
potentially harmful and/or undesired frequencies
from making their way through the amplifier
sections to the speaker(s). This serves to improve
tonal balance and to avoid distortion and possible
speaker failure. Correct use of these filters can
substantially increase the longevity and fidelity
of your audio system.
1) "Filter Mode" Control: The JX360/4 employs a
12dB per octave filter for each pair of channels
(one filter for channels 1&2 and another filter
for channels 3&4). Each of these filters can
be configured independently into one of two
filter types or defeated completely by way of the
three-position "Filter Mode" switches:
"HP" (High-Pass): Configures the filter to
attenuate frequencies below the selected filter
frequency at a rate of 12dB per octave. This is
useful for connection of component speakers
to one or both of the JX360/4's channel pairs in
a bi-amplified system.
Off": Defeats the filter completely, allowing
the full range of frequencies present at the
inputs to feed the amplifier. This is useful
for systems utilizing outboard crossovers or
requiring full-range reproduction from one or
both of the JX360/4's channel pairs.
JL Audio
"LP" (Low-Pass): Configures the filter to
attenuate frequencies above the selected filter
frequency at a rate of 12dB per octave. This is
useful for connection of subwoofer(s) to one
or both of the JX360/4's channel pairs in a
bi-amplified system.
2) "Filter Freq. (Hz)" A simple rotary control
in each channel section adjusts the filter
cutoff frequency of the filter type you have
selected with the "Filter Mode" switch. This
control will have no effect if you have selected
the "Off" position for the "Filter Mode").
Each filter in the JX360/4 is fully variable
between 50 Hz and 200 Hz. The "80"
Hz position is a good starting point for
tuning systems utilizing typical subwoofers
and component or coaxial speakers.
JX360/4
preouts
The JX360/4 incorporates a pass-through
preamp output (Preouts) section, so that
additional amplifiers can be easily added to
the system. This pass-through pre-amp output
delivers a summed stereo signal, combining the
Ch 1 and 3 signals into a Left Preamp Output
Signal and the Ch. 2 and 4 signals into a Right
Channel Preamp Output signal. Only signals
applied to the Low-Level inputs are passed
through the Preouts. Input signals applied to
the High-Level inputs will not pass through the
Preouts.
The preamp output signal is not affected by
any crossover filter selected (if the input signal is
full-range, the preamp output will be full-range).
Note: The signal level of the "Preouts" is always
line-level (low voltage).
9