12
| JL Audio - 300/4
v3
Owner’s Manual
13
C) Subwoofer Level Control Only
Req uired: a source unit or processor with left,
right and dedicated subwoofer outputs.
Inp ut Connections: The main stereo pair of
source unit outputs is connected to the
front inputs of the 300/4v3 (select “2ch”
on the “InputMode” switch in the “Front
Input Section”). The source unit’s dedicated
subwoofer output is connected to the
subwoofer amplifier inputs.
Res ult: with this option, the user has the ability
to control the absolute level of the subwoofer
channel relative to the HF channels, but
cannot fade the front and rear HF channels
relative to each other.
I M P O R TA N T
!
Set the subwoofer amplifier’s “Input Sens.”
with the source unit’s subwoofer level control
set at 3/4 of full output.
D) Front to Rear HF Fading and
Subwoofer Level Control
Req uired: a source unit or processor with
front and rear pairs of stereo outputs plus a
dedicated subwoofer output.
Inp ut Connections: one stereo pair (front,
typically) of source unit outputs is connected
to the front inputs of the 300/4v3. The second
stereo pair of source unit outputs (rear,
typically) is connected to the rear inputs of
the 300/4v3 (select “4ch” on the “Input Mode”
switch in the “Front Input Section”). The
source unit’s dedicated subwoofer output is
connected to the subwoofer amplifier inputs.
Res ult: with this option, the user has the ability
to fade the front and rear HF channels relative
to each other and also has the ability to
control the absolute level of the subwoofer
channel relative to the HF channels.
I M P O R TA N T
!
Set the subwoofer amplifier’s “Input Sens.”
with the source unit’s subwoofer level control
set at 3/4 of full output.
Crossover Setup for Bi-Amplified System with one
300/4v3 and a separate subwoofer amplifier:
Once the input and preamp output
sections have been configured appropriately,
go to the “Front Filter Controls” and
“Rear Filter Controls” You will set both
control sections identically to start:
Select “x1” on the “Freq. Range” switch, “HP”
(high-pass) on the “Filter Mode” switch and
“12dB” or “24dB” on the “Filter Slope” switch
and an appropriate “Filter Freq.” (80 - 90 Hz is a
good starting point). Select the same settings for
the “Rear Filter Controls”.
After proper adjustment of the 300/4v3’s
front and rear “Input Sens.” controls and the
subwoofer amplifier’s input sensitivity controls,
you can fine tune filter frequencies and slopes and
attenuate either pair of channels to achieve proper
balance. For proper adjustment of the “Input
Sens.” controls of the 300/4v3 use the method
shown in Appendix A (page 14). For precise filter
frequency information for the 300/4v3 refer to
Appendix D (page 18). Refer to the subwoofer
amplifier owner’s manual for proper adjustments.
Crossover Setup for Bi-Amplified System
with one 300/4v3:
Once the input sections have been configured
appropriately, go to the “Rear Filter Controls”.
Select “x1” on the “Freq. Range” switch, “LP”
(low-pass) on the “Filter Mode” switch and
“12dB” or “24dB” on the “Filter Slope” switch
and an appropriate “Filter Freq.” (80-90 Hz is a
good starting point).
Next, turn your attention to the “Front Filter
Controls” and select “x1” on the “Freq. Range”
switch, “HP” (high-pass) on the “Filter Type”
switch and “12dB” or “24dB” on the “Filter
Mode/Slope” switch and an appropriate “Filter
Freq.” (again, 80-90 Hz is a good starting point).
After proper adjustment of the front and rear
“Input Range” and “Input Sens.” controls using
the method shown in Appendix A (page 14), you
can fine tune filter frequencies and slopes and
attenuate either pair of channels to achieve proper
balance. For precise filter frequency information
refer to Appendix D (page 18).
bi-amplified system with one 300/4v3 in
four-channel mode and a separate
subwoofer amplifier
This configuration requires that the separate
subwoofer amplifier has a built-in low-pass filter.
All JL Audio subwoofer amplifiers have this
feature.
In this configuration, the front channels of
the 300/4v3 will drive front component speakers
(stereo 75W x 2) with high-pass filtering. The rear
channels will drive rear component speakers in
stereo (75W x 2), also with high-pass filtering.
The separate amplifier will drive the subwoofer
system with low-pass filtering (select a filter
frequency of 80-90 Hz to start).
Input connection options for a bi-amplified
system with one 300/4v3 and a separate subwoofer
amplifier are as follows:
A) No User Adjustability:
Req uired: a basic source unit or processor with
left and right stereo outputs.
Inp ut Connections: a single pair of stereo
source unit outputs is connected to the
front inputs of the 300/4v3 (select “2ch”
on the “Input Mode” switch in the “Front
Input Section”) and also connected to the
subwoofer amplifier inputs via a pair of
“Y-Adaptors” like the JL Audio ECS model
XD-CLRAICY-1F2M. Alternatively, the
300/4v3 can receive its input from the
subwoofer amplifier’s preamp output set
to “full-range” mode.
Res ult: the relative level of the LF and front
and rear HF channels will be fixed by
the 300/4v3’s “Input Sens.” settings
(as well as the subwoofer amplifier’s
settings) and will not be user adjustable
from the front of the vehicle.
B) Fade Subwoofer Level vs. HF Level
Req uired: a source unit or processor with front
and rear pairs of stereo outputs.
Inp ut Connections: one stereo pair of source unit
outputs is connected to the front inputs of the
300/4v3 (select “2ch” on the “Input Mode”
switch in the “Front Input Section”). The
second stereo pair of source unit outputs is
connected to the subwoofer amplifier inputs.
Res ult: with this option, the user has the
ability to fade the level of the subwoofer
amplifier’s input relative to the HF
channels, but cannot control front-to-
rear fading of the HF channels. The
relative level of the front and rear HF
channels will be fixed by the 300/4v3’s
“Input Sens.” settings and will not be user
adjustable from the front of the vehicle.
fading the signal to the subwoofer amplifier.