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Owner’s Manual
Owner’
s Manual
One side is louder than the other
• Are both Level controls set to the same posi-
tion?
• Check your source signal to make sure the left
and right signals are balanced.
• Are the speaker impedances matched? Differ-
ent speaker loads can cause different volume
levels on each side.
• Try switching sides: Turn off the amp, swap the
speaker cables at the amp, turn the amp back
on. If the same side is still louder, the problem
is with your speaker cabling. If the other side is
louder now, the problem is with the mixer, the
amp, or the line-level cabling.
Poor Bass response
• Check the polarity of the speaker cable connec-
tions. You may have your positive and negative
reversed at one end of one speaker cable.
As the music gets loud, the amp shuts down
• Make sure the OL LEDs are not lighting con-
tinuously. If so, turn down the signal source or
the amp Level controls.
• Can the amp breathe? It needs plenty of fresh
air to stay cool.
Do not block the ventilation
holes.
Noise/Hum
• Check the signal cable between the mixer and
the amplifier. Make sure all connections are
good and sound.
• Make sure the signal cable is not routed near
AC cables, power transformers, or other EMI-
inducing devices.
• Is there a light dimmer or other SCR-based
device on the same AC circuit as the amplifier?
Use an AC line filter, or plug the amplifier into a
different AC circuit.
• If possible, listen to the signal source with
headphones plugged into the console. If it
sounds noisy there, the problem is not in the
amplifier.
• Is there a cable-TV audio feed in your system?
An incorrect ground may causes a "ground loop"
hum.
• Sometimes it helps to plug all the audio equip-
ment into the same AC circuit so they share a
common ground.
Repair
Service for Mackie products is available at a factory-
authorized service center. Service for Mackie products
living outside the United States can be obtained through
local dealers or distributors.
If your amplifier needs service, follow these instructions:
1. Review the preceding troubleshooting suggestions.
Please.
2. Call Tech Support at 1-800-898-3211, 7 am to 5 pm
PST, to explain the problem and request a Service
Request Number. Have your serial number ready.
You must have a Service Request Number before
you can obtain warranty service.
3. Keep this owner’s manual and the detachable
linecord. We don’t need them to repair the amp.
4. Pack the amplifier in its original package, includ-
ing endcaps and box. This is VERY IMPORTANT.
Mackie is not responsible for any damage that oc-
curs due to non-factory packaging.
5. Include a legible note stating your name, shipping
address (no P.O. boxes), daytime phone number,
Service Request Number, and a detailed description
of the problem, including how we can duplicate it.
6. Write the Service Request Number in BIG PRINT
on top of the box. Units sent without the SR number
will be refused.
7. Tech Support will tell you where to ship the ampli-
fier for repair. We suggest insurance for all forms of
cartage.
8. You will need to contact the authorized service
center for their latest turn-around times. Once it’s
repaired, the authorized service center will ship it
back by ground shipping, pre-paid (if it was a war-
ranty repair).
Note:
Under the terms of the warranty, you must ship
or drop-off the unit to an authorized service center.
The return ground shipment is covered for those
units deemed by us to be under warranty.
Note:
You must have a sales receipt from an authorized
Mackie dealer for your unit to be considered for
warranty repair.
