JBL EON10 User Manual page 15

Symptom
Hum or Buzz that increases or
decreases when the mixer level equipment connected to mixer
controls are moved.
Hum or Buzz.
The inputs from INPUT 2 & 3
aren't coming out of the
OUT connector.
The speaker connected to the
OUT connector goes up and
down in volume when I adjust
the INPUT 1 control on the 1st
speaker.
Speakers feedback and howl
when the microphone volume is speakers.
turned up.
Likely Cause
Improper A/C ground or faulty
input.
Faulty cable between source
equipment and mixer.
Improper A/C grounding, ground
loops.
Excessively long unbalanced
cable run.
Improper system gain structure.
MIX/LOOP SWITCH set
improperly.
MIX/LOOP SWITCH set
improperly.
Microphones are pointed into the
Equalizer settings are incorrect.
Excessive gain.
What to do
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.
Substitute a known-good cable
for the suspected faulty cable.
Connect all speakers to a
common power circuit.
"Telescope" the audio ground by
using an XLR/F to XLR/M
adapter with Pin 1 disconnected.
Re-route audio cables away from
AC power and lighting cables.
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.
Reduce the INPUT 1, LINE 2,
and LINE 3 controls and increase
the output level of your source
devices.
Set the MIX/LOOP SWITCH to
the MIX OUT position
(depressed). See the CAUTION
in the "Switches" section of this
manual.
Disengage the MIX OUT switch.
See the CAUTION in the
"Switches" section of this
manual.
Move the speakers so they do not
point into the microphone's pick-
up pattern. See the section on
"Loudspeaker Placement and
Mounting" on page 20.
Locate the feedback frequency
and reduce it using the mixer EQ
or an external equalizer.
Reduce the gain at the mixer and
move the microphone closer to
the sound source. 15