JBL MA6004 User Manual

CONTROLS AND
SETUP
SETTING THE
CROSSO
VER(S)
Determine your system plans and set
the crossover mode switch accordingly.
If your system design does not include
a subwoofer with the MA6004, set the
crossover mode to FLAT; if you are using
speakers that are 5 inches in diameter or
larger, skip to “Setting Input Sensitivity.”
Initially set the crossover frequency
control midway. While listening to music,
adjust the crossover for the least
perceived distortion from the speakers,
allowing them to reproduce as much
bass as possible.
For systems using a separate subwoofer,
set the crossover mode to HP (high pass)
for your full-range speakers. Adjust the
crossover frequency to limit bass and
provide increased system volume with
less distortion.
For subwoofers, choose the highest
frequency that removes vocal information
from the sound of the subwoofer.
If using the MA6004 or MA6002 to drive a
subwoofer(s), set the crossover mode to
LP (low pass).
SETTING INPUT
SENSITIVITY
1. Initially turn the INPUT LEVEL control(s)
to minimum (counter clockwise).
2. Reconnect the (–) negative lead to the
boat’s battery. Apply power to the audio
system and play a dynamic music track.
3. On the source unit, increase the volume
control to 3/4 volume. Slowly increase
the INPUT LEVEL control(s) toward
“three o’clock” until you hear slight
distortion in the music. Then reduce
the INPUT LEVEL slightly until distortion
is no longer heard.
NOTE: After the source unit is on,
blue LEDs (on the top panel) will light,
indicating the amplifier is on. If not,
check the wiring, especially the remote
connection from the source unit. Also
refer to the “Troubleshooting” guide.
SYMPT
OM LIKELY CAUSE SOLUTION
No audio No voltage at BATT+ Check voltages at
(POWER LEDs or REM terminals, amplifier terminals
are off) or bad or no ground with VOM
connection
No audio
Amplifier is Make sure amplifier
(POWER overheated cooling is not blocked
LEDs are on) at mounting location;
verify speaker-system
impedance is within
specified limits
Voltage more than 16V Check boat’s battery
or less than 8.5V on charging system
BA
TT+ connection
No audio Voltage less than 9V on Check boat’s
(POWER BATT+ connection charging system
LEDs flash)
DC voltage on Amplifier may need
amplifier output service; see enclosed
warranty card for
service information
Distorted audio Input sensitivity is
Check INPUT
not set properly, or LEVEL setting; or
amplifier or source check speaker wires
unit is defective
for shorts or grounds
Distorted audio Short circuit in Remove speaker leads
and POWER speaker or wire one at a time to locate
LEDs flash shorted speaker or
wire, then repair
Music lacks
Speakers are not Check speaker
“punch” connected properly connections for
proper polarity
TROUBLESHOO
TING

JBL MA6004 Specifications