Troubleshooting - Electro-Voice ZLX-12P-UX User Manual

7

Troubleshooting

Problem
1. No sound
2. Poor Low-
Frequency
Response
3. Intermittent output
such as cracking or
distortion
4. Constant noise
such as buzzing,
hissing or humming
5. No sound produced
with microphone
connected to INPUT
1 or INPUT 2
6. Sound is distorted
front LED is OFF,
LCD screen LIMIT is
ON
Electro-Voice
Possible Cause(s) Action
Amplifier Connect a known working test loudspeaker to the
amplifier outputs. If there is no sound, verify all the
electronics are on, the signal routing is correct, the
source is active; the volume is turned up, etc.
Correct/repair/replace as necessary. If there is sound,
the problem is wiring.
Wiring Verify you have connected the correct cables to the
amplifier. Play something at a low level through the
amplifier. Connect the test loudspeaker in parallel with
the malfunctioning line. If the sound level is gone or is
very weak, the line has a short in it (possibly a severe
scrape, pinch, or a missed connection). Using the test
loudspeaker, move down the line and test each
connection/junction until you find the problem and
correct it. Observe proper polarity.
With SUB menu If no subwoofers are used with the system, select the
cross-over frequency OFF position.
activated
Faulty connection Check all connections at amplifier and loudspeakers to
ensure they are all clean and tight. If the problem
persists, check the wiring. See problem 1.
Defective source or If noise is present, but no program material is playing,
other electronic evaluate each component as necessary to isolate the
device problem. Most likely there is a break in the signal path.
Poor system Check and correct the system grounding, as required.
grounding or ground
loop
Input gain knob is Slowly increase the input gain knob level to engage the
not in the MIC microphone pre-amp.
position
Microphone requires Use a dynamic microphone that does not require
phantom power. phantom power. If using a microphone requiring
phantom power, an external phantom power source is
needed
Input gain knob is Slowly increase the input gain knob level to engage the
not in the MIC microphone pre-amp.
position
Excessive input level Reduce the input level or loudspeaker level knobs to
prevent limit.
User Manual
en 27
2015.12 | 02 | F.01U.319.253