JBL PRX715XLF, User Manual

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20
Symptom Likely Cause What to do
No sound
Speaker not connected
to active AC power
Verify that speaker is connected and that
circuit is on. Switch on power and verify
that illuminated logo is on.
• Re-seat the power cable at both ends.
• Substitute a known-good power cable.
Speaker power cable
is faulty or improperly
connected
No sound, speaker is
connected to working AC
power but won’t come on.
Blown fuse
• Replace the fuse with the specified value
and type.
• Take your speaker to a competent
service center.
Signal source (mixer,
instrument, etc.) is not
active
No sound.
Speaker comes on.
Faulty cables and
connections
• Check VU meters on the source mixer.
• Verify that the CD/MP3 is playing.
• Use headphones to verify that the
instrument is actually sending an audio signal.
• Disconnect and re-seat signal cables.
• Replace suspected cable with a
known-good cable.
No sound with microphone
connected directly to the
MIC input.
Microphone requires 48V
phantom power
The PRX700 speakers do not supply
phantom power. Switch to a dynamic
microphone, use a battery in the microphone
(if possible), use an external phantom power
Faulty microphone cable supply. Check cable.
Faulty microphone cable
Signal sounds distorted
and very loud, OVERLOAD
light is lit most of the time.
Excessive input signal,
trying to exceed the
capabilities of
the speakers
• Reduce the output level of the source.
• Turn down the level controls on the speaker.
Signal sounds distorted
even at moderate volumes,
OVERLOAD light is not lit.
Mixer or other source
is overdriven (clipping)
Review the Owner’s Manual for your system setup
and adjust controls as needed.
• Input sensitivity (gain)
• Check gain structure of signal chain
Noise or hiss heard at
output
Noisy Source Device
Disconnect the devices that are connected to
your speaker one at a time. If the noise goes
away, the problem is with the source or the
connecting cable.
TROUBLESHOOTING