JL Audio 505 - Manual (Page 6)

the “12dB” or “24dB” position.These features will
not work with the “Sub LP Filter” switch in the
“Off” position.This is to prevent cascading the
processing of multiple amplifiers when configured in
a master / slave arrangement. If you are using an
external active crossover and would like to use the
“LF Boost” and “Infrasonic Filter” features, set the
“Amp LP Filter” switch on “12dB” and rotate the
frequency selection knob fully clockwise to the “200
Hz” position.This will activate the bass processing
features without significantly affecting the crossover
point selected by the external active crossover.
SPEAKER OUTPUTS
The 500/5 employs JL Audio's exclusive
Regulated, Intelligent Power Supply (R.I.P.S.) design
on its front and subwoofer channels.The operation
of the R.I.P.S. system is independent for each pair of
channels.This sophisticated power supply allows the
amplifier to produce its optimum power (100 watts
x 2 for the front channels and 250 W x 1 for the
subwoofer channel over a wide range of speaker
impedances. Unlike conventional amplifiers that
require a specific impedance to produce optimum
power, the R.I.P.S.-equipped 500/5 gives you the
freedom to use a variety of speaker configurations
that achieve final nominal impedances between 1.5
– 4 Ω per channel (without sacrificing power output
or sound quality). When bridged, the front channel
pair will optimize output between 3 – 8 Ω.The rear
channel pair will optimize output between 6 - 8 Ω.
The operation of the R.I.P.S. circuitry is entirely
automatic and adjusts itself every time the amplifier
is turned on according to the lowest impedance
present at the speaker load.There are no user
controls to configure.The system operates through
multiple stages of impedance optimization, choosing
the stage most appropriate to the actual impedance
of the speakers you connect to it.
Re
Freq.
x1/
Filter F
Subwoofer Output (250Wx1)
Filter
/24dB
q. (Hz)
If you connect a load higher than 4 Ω nominal
per channel (or 8 Ω in bridged mode for the front
and rear channels), power will drop by half with
every doubling of impedance above 4 Ω stereo /
8 Ω mono. If you connect a load lower than 1.5Ω
nominal per channel, the amplifier protection
circuitry activates a “safe” mode which reduces
amplifier power to protect the circuitry from
failure (the yellow “Low Ω” LED lights to indicate
that this has happened). See page 12 for details.
Speaker loads below 1.5 Ω nominal per channel
are not recommended and may cause the amplifier
output to distort excessively.
The rear channels of the 500/5 do not employ
R.I.P.S. optimization and are designed to deliver rated
power into loads between 3 and 4 Ω per channel.
Operating the rear channels below 3 Ω may result in
excessive distortion and/or shutting down of these
channels and is not recommended.
BRIDGING CONSIDERATIONS
Bridging is the practice of combining the output
of two amplifier channels to drive a single load.
When bridged, each channel produces signals of
equal magnitude, but opposite polarity.The
combined output of the two channels provides
twice the output voltage available from a single
channel.The 500/5 has been designed for bridging
of its front and rear channel pairs without the need
for input inversion adaptors.
Operating bridged channel pairs into a load lower
than 3 Ω is not recommended.
To bridge a pair of channels, use the “Left +” and
“Right –” speaker connectors only (the “Left –”
and “Right +” remain unused).Then connect a
mono signal to both left and right RCA inputs for
ction
ut Sens.
ght Ch.
Front Speaker Outputs
I M P O RTA N T !
I M P O RTA N T !
I M P O RTA N T !
JL AUDIO 500/5 11
will be full-range.) This signal is not affected by the
“LF Boost” or “Infrasonic Filter” processing
selected for the amplifier. When the 500/5 is being
used to drive front, rear and subwoofer speaker
systems, this preamp output mode will deliver a
summed front/rear signal to an additional
subwoofer amplifier, while permitting fading of the
front and rear speaker systems from the source
unit.
3) “Front”: This is a pass-through mode for the
preamp output, delivering the same signal that is
being fed to the “Front Input Section” of the
amplifier (If the input signal is full-range, the preamp
output will be full-range.) This signal is not affected
by the “LF Boost” or “Infrasonic Filter” processing
selected for the amplifier.
If the “Output Mode” switch is in the “Sub LP”
position and the “Sub LP Filter” switch is in the
“Off” position, the preamp output will be a
12dB/octave low-pass with the “Bass Control”
processing added to it. THIS IS NOT A
PREFERRED OPERATING MODE. DO NOT
USE THIS MODE FOR MASTER / SLAVE
CONFIGURATIONS.
Note:The signal level of the “Preamp Output” is
affected by the setting of the “Input Voltage”
switches (of the input section(s) chosen by the
“Signal From” switch). See the “Input Voltage
Range” section (page 6) for details on input voltage
settings.The preamp output level is not affected by
the “Input Sens.” rotary controls.
C AU T I O N !!
BASS PROCESSING
The 500/5's subwoofer channel control section
also includes some basic bass processing tools.
These consist of two primary components: a
fixed-frequency, 24 dB / octave infrasonic filter and
a fixed-frequency / “Q”, single-band equalizer
centered at 48 Hz.
1) “Infrasonic Filter”: The infrasonic filter is a
24 dB / octave high-pass filter, with a fixed cutoff
frequency of 30 Hz.This filter is designed to
conserve amplifier power and protect subwoofer
systems without audibly degrading the sub-bass
output. With ported enclosures, the use of the
infrasonic filter is highly recommended to protect
the speaker(s) from excessive excursion below box
tuning. With sealed enclosures, the use of the filter is
less necessary, but can still help protect the speaker
system.The infrasonic filter can be completely
defeated by selecting the “Off” position on the
“Infrasonic Filter” switch.This bypasses all signal
from flowing through the circuit.
2) LF (Low-frequency) Boost: This feature
allows the user to control the boost of a fixed “Q”,
fixed-frequency equalization band centered at 48
Hz.The “LF Boost” rotary control determines how
much boost (in dB) you are adding to the bass
signal. A range of 0-15 dB of boost is available. If no
boost is desired, rotate the “LF Boost” control fully
counterclockwise.
The “Remote Bass Port” allows the connection
of an optional remote boost knob (the RBC-1)
that can be mounted in the front of the vehicle.
This optional control takes the place of the “LF
Boost” knob on the amplifier when connected
and bypasses the “LF Boost” rotary control on
the amplifier.
The “LF Boost” and “Infrasonic Filter” features
will only operate when the subwoofer channel's
filter is activated with the “Sub LP Filter” switch in
I M P O RTA N T !
Subwoofer Channel Control Section
Input Sens. Input Voltage
Low/High
Independent Sub Input
Sub LP Filter
Off/12dB/24dB
Filter Freq. (Hz)
Remote Bass
Port
Off/30Hz
LF Boost (dB)
Input From:
Ind./F+R/Front
Infrasonic Filter
Left Right
+1 +13
+3
+7
+10
10 JL AUDIO 500/5