Troubleshooter - Harman JBL Professional VL6A Guia Del Usuario

Symptom
There is no sound.
No sound, the amplifier is
connected to electrical
power, but does not turn
on.
The amplifier turns on but
there is no sound.
The sound is distorted
and too loud, the clip LED
is lit most of the time.
Sound is distorted even
at moderate volume and
the clip LED is not lit.
Noises or whistles are
heard at the exit.
Noise and humming that
increase or decrease
when the level controls of
the mixing device are
moved.
Noise or buzzing
Probable cause
The amplifier is not connected to
electrical power.
The power is not turned on.
The power cord of the amplifier is
faulty or improperly connected.
Signal source (Mixer, processor,
...) is not sending signal.
The mixer device or another
source is overloaded.
Excessive input signal, trying to
exceed the capacity of the
speakers.
The mixer or other signal source is
saturated.
Noise source device.
Inappropriate AC ground or faulty
equipment connected to the output
of the mixer.
A defective cable between the
equipment source and the mixer.
Inappropriate AC grounding,
ground loops.
The size of the unbalanced cable
is too long.
Optimize the structure of the
system gain.

TROUBLESHOOTER

Check if there is a damaged cord or if the amplifiers are
connected to the mains.
Turn on the power and check that the power LED is on.
Check the power cord at both ends.
Replace with a good quality power cord.
Check the amplifier if the signal LED is on.
Check the Owner's Manual of your mixer device and
adjust the controls as necessary.
Once this is done, review the Quick Start Guide
instructions in this manual.
Reduce the output level of the source.
Decrease the volume control of the amplifier.
Use more additional VL6 boxes.
Check the owner's manual of your mixer device and adjust
the controls as necessary.
•
Input sensitivity;
•
Channel Faders;
•
Main Faders.
Disconnect the devices that are connected to your system
one at a time.
If the noise disappears, the problem is at the source or the
connecting cable.
Disconnect or mute the channels one at a time, isolating
the problem. Refer to the user manual of the faulty device
for troubleshooting or help.
Replace defective cable with good quality one.
•
"Raise" the audio using an XLR/F to XLR/M adapter
at one end.
Re-route audio cables away from power and light cables.
•
Use the balanced output (if available) on your mixer
or source of your VL system.
Reduce the level of the INPUT controls and increase the
output level of your source device.
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What to do