JBL PRX710, User Manual

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Hum or Buzz that
increases or decreases
when the mixer level
controls are moved
Improper A/C ground or
faulty equipment
connected to mixer input
Disconnect or mute channels one at a time to
isolate the problem. Refer to the owner’s manual of
the faulty equipment for troubleshooting help.
Faulty cable between
source equipment and
mixer
Substitute a known-good cable for the suspected
faulty cable.
Hum or Buzz
Improper A/C grounding,
ground loops
• “Telescope” the audio ground by using an XLR/F
to XLR/M adapter on one end.
• Re-route audio cable away from AC power and
lighting cables.
Excessively long
unbalanced cable run
• Use the balanced outputs (if available) of your
mixer or source equipment to drive your
EON speakers.
• Use a “DI” (direct injection) box to convert
your unbalanced equipment output to a
balanced output.
Improper system gain
structure
Review the Owner’s Manual for your system
setup and adjust controls as needed.
• Input sensitivity (gain)
Speakers feedback and
howl when the microphone
volume is turned up
Microphones are pointed
into the speakers
Move the speakers so they do not point to the
microphone’s pickup pattern.
Equalizer settings are
incorrect
Locate the feedback frequency and reduce it
using the mixer EQ or an external equalizer.
Excessive gain
Reduce the gain at the mixer and move the
microphone closer to the sound source.
Too much low frequencies
when playing back
prerecorded music
Recorded music
with excessive
low frequencies
Switch the EQ switch to “flat.”
Section 7: Connection Types