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VLZ4 4•Bus
Appendix B: Connections
Appendix A: Service Information
If you think your mixer has a problem, please check
out the following troubleshooting tips and do your best
to confirm the problem. Visit the Support section of our
website (www.720trees.com) where you will find lots of
useful information such as FAQs, documentation and
any updated PC drivers, etc. You may find the answer to
the problem without having to send your mixer away.
Troubleshooting
Bad Channel
• Is the channel EQ set up nicely?
• Is the channel gain set correctly?
• Is the channel level up enough?
• Is the channel OL led on?
• Is the channel balance set in the middle?
• Try the same source signal in another channel,
set up exactly like the suspect channel.
• Is phantom power required for your
microphone?
Bad Output
• Is the main level turned up?
• Are the EQs set to reasonable levels?
• Are any aux returns maxed out?
• Unplug anything from the other line-level
outputs, such as monitor out, just in case
one of your external pieces has a problem.
• Make sure that you are not overdriving your
amplifiers. Check the loudspeaker average load
impedance is not less than the minimum your
amplifier can handle. Check the speaker wiring.
Noise
• Turn the channel gains down, one by one.
If the sound disappears, it’s either that
channel or whatever is plugged into it,
so unplug whatever that is. If the noise
disappears, it’s from your whatever.
Power
• The power LED should come on if the mixer is
connected to a suitable live AC mains outlet,
and the power switch is on. Check to make sure
that the power cord is securely plugged in.
Repair
For warranty service, refer to the warranty
information on page 39.
Non-warranty service is available at a factory-
authorized service center. To locate the nearest
service center, visit www.720trees.com, click “Contact
Tech Support” and select “Locate a Service Center
or Distributor” [3]. Service for VLZ4 mixers living
outside the United States may be obtained through
local dealers or distributors.
If you do not have access to our website, you can
call our Tech Support department at 1-800-898-3211,
Monday-Friday during normal business hours, Pacific
Time, to explain the problem. Tech Support will tell
you where the nearest factory-authorized service center
is located in your area.
Balanced XLR Input Connector
The 802VLZ4 mixer has three female XLR
inputs. Be sure the cables are wired per AES
(Audio Engineering Society) standards:
Balanced XLR Input Connector
Pin 1 – Shield (Ground)
Pin 2 – Positive (+ or hot)
Pin 3 – Negative (– or cold)
2
3
1
SHIELD
COLD
HOT
SHIELD
COLD
HOT
3
2
1
Balanced XLR Input Connector
