channel relative to the three HF channels with the
source unit’s subwoofer level control.
Set the subwoofer amplifier’s
“Input Sens.”
with
the source unit’s subwoofer level control set at 3/4
of full output. Refer to the subwoofer amplifier
owner’s manual for proper adjustment.
Crossover setup for bi-amplified 3.1 system with one
450/4 and a separate subwoofer amplifier:
Once the input and preamp output sections have
been configured appropriately, go to the
“CH 1&2
Filter Section”.
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.”
(80-90 Hz
is a good starting point). The
“Infrasonic Filter”
and
“Bass EQ”
features cannot be used in this mode.
Next, turn your attention to the
“CH 3&4 Input
Section”
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 450/4’s CH
1&2 and CH 3&4, and the subwoofer amplifier’s
“Input Range”
and
“Input Sens.”
, you can fine
tune filter frequencies and slopes and attenuate
the center channel or the left and right channel pair
with the
“Input Sens.”
controls to achieve proper
balance. For proper adjustment of the
“Input
Sens.”
controls of the 450/4 use the method
shown in Appendix B (page 20). For precise filter
frequency information for the 450/4 refer to
Appendix A (page 20). Refer to the subwoofer
amplifier owner’s manual for proper adjustments.
I M P O RTA N T
!
BI-AMPLIFIED 5.1 SYSTEM WITH
MULTI-CHANNEL SOURCE, ONE 450/4 IN
THREE-CHANNEL MODE,A JL AUDIO 300/2
AMPLIFIER DRIVING REAR SURROUND
SPEAKERS AND A SEPARATE SUBWOOFER
AMPLIFIER (JL AUDIO 500/1 OR 1000/1
RECOMMENDED)
This configuration is identical to the 3.1 system
configuration with Input Option A, except for the
addition of a JL Audio 300/2 two-channel amplifier to
drive rear surround speakers, effectively creating a
true 5.1 multi-channel system with left-front, center-
front, right-front, left-rear and left-right channels.
The 300/2 in two-channel stereo mode is
perfectly matched to the 450/4 in three channel Left,
Center, Right mode.The system will deliver 150 W x
5 to power the component speaker systems plus
the output of an additional amplifier to the
subwoofer system.
To add this capability, connect the 300/2’s
inputs to the rear (surround) outputs of a multi-
channel processor or source unit and set the
300/2’s
“Amp Filter”
in
“HP”
mode with a
“12dB”
or
“24dB”
filter slope.
JL AUDIO
450/4
17
Result:
True left, center and right channels with
multi-channel material, derived center channel with
stereo material. Rear-surround channels are unused.
User adjustability of left, center and right channels
depends on source unit/processor. Subwoofer level is
user adjustable.
Set the subwoofer amplifier’s
“Input Sens.”
with
the source unit’s subwoofer level control set at 3/4
of full output. Refer to the subwoofer amplifier
owner’s manual for proper adjustment.
The “Summed Center Channel” methods outlined
below do not create a true center channel, they
simply sum left and right signals to the center
speaker system. This is not as desirable as a true
center channel from a multi-channel source, but it
can be used to create a convincing sound stage in
some applications.
B) “Summed Center Channel”,
No User Adjustability
Required:
a basic source unit or processor with left
and right stereo outputs.
Input Connections:
a single pair of stereo source
unit outputs, connected to the CH 1&2 inputs of
the 450/4 (select
“2ch”
on the
“Input Mode”
switch in the
“CH 1&2 Input Section”
). Connect
the subwoofer amplifier inputs to the preamp
outputs of the 450/4 (Select
“1&2”
on the
“Signal
From”
switch in the
“Preamp Output Section”
).
Result:
the relative level of all channels will be fixed
by the 450/4’s
“Input Sens.”
settings and will not be
user adjustable from the front of the vehicle.
I M P O RTA N T
!
I M P O RTA N T
!
C) Fade Between “Summed Center Channel”
Level and Left/Right Level with Non-Fading
Subwoofer Level
Required:
a source unit or processor with front and
rear pairs of stereo outputs.
Input Connections:
one pair of stereo source unit
outputs is connected to the CH 1&2 inputs of the
450/4 (select
“4ch”
on the
“Input Mode”
switch in
the
“CH 1&2 Input Section”
). A second pair of
source unit outputs is connected to the CH 3&4
inputs. Connect the subwoofer amplifier inputs to
the preamp outputs of the 450/4 (Select
“ALL”
on
the
“Signal From”
switch in the
“Preamp Output
Section”
).
Result:
with this option, the user has the ability to
adjust the relative level of the “Summed Center
Channel” input relative to the Left and Right channel
pair via the source unit’s fader control. Subwoofer is
non-fading.
D) Fade Between “Summed Center Channel”
Level and Left/Right Level with Separate
Subwoofer Level Control
Required:
a source unit or processor with front
and rear pairs of stereo outputs plus a dedicated
subwoofer output.
Input Connections:
one pair of stereo source unit
outputs is connected to the CH 1&2 inputs of the
450/4 (select
“4ch”
on the
“Input Mode”
switch
in the
“CH 1&2 Input Section”
). A second pair of
source unit outputs is connected to the CH 3&4
inputs.The source unit’s dedicated subwoofer
output is connected to the subwoofer amplifier’s
inputs. In this mode, the 450/4’s preamp output is
not used.
Result:
with this option, the user has the ability to
fade between the “Summed Center Channel” level
and the Left and Right channel levels via the
source unit’s fader control and also has the ability
to control the absolute level of the subwoofer
16
JL AUDIO
450/4
