JL Audio XD400/4 - Handbuch (Seite 13)

13
ENGLISH
14), you can fine tune filter frequencies and
attenuate either pair of channels to achieve
proper balance. For precise filter frequency
information refer to Appendix B (page 15).
multi-amPliFier sYstems
Using the “Preamp Outputs” of the
XD400/4, it is easy to configure many
different multi-amplifier systems.
The most common type involves the
addition of a subwoofer amplifier, such
as the XD600/1. Common configurations
of such a system are described below.
bi-amplified system with one Xd400/4 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 amplifiers have this feature.)
In this configuration, channels 1&2 of the
XD400/4 will drive front component speakers
in stereo with high-pass filtering. Channels 3&4
will drive rear component speakers in stereo, also
with high-pass filtering. The separate amplifier
will drive the subwoofer system with low-pass
filtering (80 Hz is a good starting point).
Here are three possible configuration options:
A) 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 “CH 1 (Left)” and
“CH 2 (Right)” inputs of the XD400/4 (select
“2 Ch.” on the “Input Mode” switch). 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
XD400/4’s “Input Sens.” settings and will not
be user adjustable from the front of the vehicle.
B) 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
“CH 1 (Left)” and “CH 2 (Right)” inputs of
the XD400/4 (select “2 Ch.” on the “Input
Mode” switch). 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.
Set the subwoofer amplifier’s “Input Sens.”
with the source unit’s subwoofer level control
set at 3/4 of full output.
C) 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 of source unit
outputs is connected to the “CH 1 (Left)” and
“CH 2 (Right)” inputs of the XD400/4.
The second stereo pair of source unit outputs
is connected to the “CH 3 (Left)” and “CH
4 (Right)” inputs of the XD400/4 (select
“4 Ch.” on the “Input Mode” switch). The
source unit’s dedicated subwoofer output is
connected to the subwoofer amplifier inputs.