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| JL Audio - MHD900/5 Owner’s Manual
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tYPiCal installation sequenCe
The following represents the sequence for
a typical amplifier installation, using an
aftermarket source unit or OEM Interface
processor (like the CleanSweep® CL441dsp).
Additional steps and different procedures may
be required in some applications. If you have
any questions, please contact your authorized
JL Audio dealer for assistance.
1)
Disconnect the negative battery post
connection and secure the disconnected cable
to prevent accidental re-connection during
installation.
This step is not optional!
2) Run positive and negative power wire
from the battery location to the amplifier
mounting location, taking care to route it
in such a way that it will not be damaged
and will not interfere with vessel operation.
4 AWG is the minimum recommended
wire size for this amplifier. Use a 2 AWG
or 1/0 AWG main power wire with a power
distribution block when additional amplifiers
are being installed with the MHD900/5 and
powered from the same main power wire.
3)
Connect power wire to the positive battery
post. Fuse the wire with an appropriate fuse
block (and connectors) within 18 inches (45
cm) wire length of the positive battery post.
This fuse is essential to protect the vessel.
Do not install the fuse until the power wire
has been connected to the amplifier.
4)
Connect negative power wire to the negative
battery post. Use the same size power wire as
the wire connected to the “
+12V
” connection.
5)
Run signal cables (RCA cables) and remote
turn-on wire from the source unit or interface
processor to the amplifier mounting location.
6)
Run speaker wire from the speaker systems to
the amplifier mounting location.
7)
Securely mount the amplifier using
appropriate hardware. (See page 8 for detailed
mounting instructions).
8)
Connect the remote turn-on wire and the
positive and negative power wires to the
amplifier’s power connector plug. Then insert
the power connector plug into the amplifier’s
power connector receptacle, pushing firmly.
9)
Connect the RCA input cables
to the amplifier.
10)
Connect the speaker wires to the speaker
connector plugs and insert the plugs firmly
into the speaker connector receptacles.
11)
Carefully review the amplifier’s control
settings to make sure that they are set
according to the needs of the system.
12)
Install power wire fuse (60A for a
single MHD900/5) and reconnect the negative
battery post terminal.
13)
Turn on the source unit at a low level
to double-check that the amplifier is
configured correctly. Resist the temptation
to crank it up until you have verified the
control settings.
14)
Make necessary adjustments to the input
sensitivity controls to obtain the right
overall output and the desired balance
in the system. See Appendix C (pages 18, 19)
for the recommended input sensitivity
setting method.
15)
Enjoy the fruits of your labor with your
favorite music.
ProduCt desCriPtion
The JL Audio MHD900/5 is a very powerful
and compact five-channel amplifier utilizing
patented Single Cycle Control™ Class D
technology for all channels. This groundbreaking
technology delivers reference-grade, full-
range sonic performance while requiring
far less current from the vessel’s electrical
system than a conventional amplifier.
JL Audio’s exclusive R.I.P.S. power supply
design optimizes the output of each channel
section for any impedance between 1.5 and 4
ohms per channel (3-8 ohms bridged on front
and rear sections) allowing you to get full use of
the MHD900/5’s performance capabilities with a
wide range of speaker systems.
The tightly regulated power supply design also
means that the MHD900/5’s clean power output
capability remains stable over a wide range of
vessel voltages, resulting in enhanced fidelity.
The MHD900/5 flexible, studio-grade signal
processing allows it to be deployed in several
different system configurations:
1) As a five-channel amplifier in a bi-amplified
system, driving four satellite speakers (100W x
4), plus a subwoofer system (500W x 1).
2) As a very powerful three-channel amplifier
in a bi-amplified system, driving two satellite
speakers (150W x 2, bridged), plus a subwoofer
system (500W x 1).
3) As a five-channel amplifier in a tri-amplified
system, driving two tweeters (100W x 2), plus
two woofer/mids (100W x 2), plus a subwoofer
system (500W x 1). An external 2-way
crossover is required for this application.
The MHD900/5’s flexible input and
crossover sections permit operation with
a wide variety of source units and system
configurations. It can be operated with a single
pair of stereo inputs, with two pairs of stereo
inputs (front and rear) or with separate inputs
for its front, rear and subwoofer channels.
As we said, it’s very flexible.
