Troubleshooting - Harman JBL PROFESSIONAL MAX Serie Manual De Usuario

Symptom
It does not emit sound.
No sound, the powered speaker is
connected to the mains, but it does
not work.
It does not emit sound. The powered
speaker turns on.
It does not emit sound with a
microphone connected directly to the
MIC/LINE input.
Distorted and very loud signal
sounds.
Distorted signal sounds even at
moderate volumes, LIMIT light is
not lit.
Too much hiss in the sound, the mixer
controls are at very low settings.
Noise or hiss at the exit.
Buzz that increases or decreases
when you move the mixer level
controls.
Buzz
20
Probable cause
Powered speaker not connected
to AC mains
Power off
The powered speaker is in
sleep mode
The powered speaker's power
cord is defective or not
connected properly.
The signal source (turntable,
instrument, etc.) is not sending.
Defective cables and
connections
Microphone requires Phantom
power (48V)
Excessive input signal,
exceeding speaker capacities
The mixer table or other source
is overloaded
Inappropriate gain structure
Noisy source device
Inadequate AC power or
defective equipment connected
to mixer input
Faulty cable between source
equipment and mixer
Improper ground circuits, AC
power
Excessively long and
unbalanced cable run
Inadequate system gain
structure

TROUBLESHOOTING

What to do
Make sure the powered speaker is plugged in and the product is turned on.
Turn on the power and check if the graphic display is lit.
Apply an audio signal to any input to activate the equipment.
• Reattach the power cord at both ends.
• Replace with a good quality power cord.
• Check the VU meters on the source mixer.
• Check if the external device is playing.
• Use headphones to verify that the instrument is actually sending an audio
signal.
• Disconnect and reconnect signal cables.
• Replace the cable that appears to be defective with a good quality cable.
MAX does not provide Phantom power (48V). Replace to a dynamic microphone,
use a battery powered microphone (if possible), use an external Phantom power
supply (48V) for condenser-type microphones.
• Reduce the source output level.
• Reduce the level controls into the speaker.
• Use additional MAX speakers.
Review your mixer Owner's Manual and adjust the controls as needed.
• Input sensitivity (gain).
• Channel faders.
• Main faders, once you are done, review the instructions in the Quick Start
section of this guide.
• Make sure the MIC/LINE switch is in the proper position.
• The operation of the Mic/Line switch will be slightly different.
• Reduce the level settings on the speaker. Review your mixer Owner's
Manual and adjust the controls as needed.
• Input sensitivity (gain).
• Channel faders.
• Master faders.
Disconnect the devices that are connected to the powered speaker one at a time.
If the noise disappears, the problem is with the source or the connecting cable.
Turn off or mute channels one at a time to isolate the problem. Consult the
Owner's Manual of the defective equipment for troubleshooting assistance.
Replace the cable that appears to be defective with a good quality cable.
• Disconnect the audio jack ground with an XLR/F to XLR/M adapter at one
end.
• Route audio cables away from AC power and lighting cables.
• Use balanced outputs (if available) from the mixer or source equipment to
drive the MAX speaker.
• Use a DI converter to convert your equipment's unbalanced output into a
balanced output.
Lower input level controls and increase the output level of source devices.