28
The bass frequencies diminish when
standing center, but get louder as you
approach one side!
•
Check the polarity of the speaker cable
connections. You may have your positive
and negative connections reversed at
one end of one speaker cable.
As soon as the music gets loud, the mixer
shuts down!
•
Check the
LEVEL
meters. Be sure that
the
CLIP
LED is not lighting up
frequently or continuously.
•
Make sure there is room behind the
powered mixer to provide sufficient
ventilation to the heatsink. If it gets too
hot, it will shut down the show.
•
Is the total speaker impedance connected
to each amplifier 2 ohms or greater? If
the impedance is too low, the amplifier
may overheat and shut down.
It hurts when I touch my arm, or my leg, or
even my head!
•
You have a broken finger.
Bad sound!
•
Is it loud and distorted? Follow the
procedures described in the “Quick
Start” section to verify that the levels are
set properly.
•
Is the input connector plugged completely
into the jack? Check the speaker connec-
tions and verify that all connections are
tight and that there are no stray strands of
wire shorting across the speaker terminals.
•
Keep practicing.
Noise/Hum
•
Turn the channel
VOLUME
knobs down
one by one. If the noise disappears, it’s
either that channel or whatever is
plugged into it. If not, turn down the
EFX
TO MAIN
control. If the noise disappears,
it could be coming from an external
effects device plugged into the
EFFECTS
RETURN
jack(s).
•
Make sure all connections to the pow-
ered mixer are good and sound.
•
Make sure none of the signal cables are
routed near AC cables, power transform-
ers, or other EMI-inducing devices.
•
Is there a light dimmer or other SCR-
based device on the same AC circuit as
the powered mixer? Use an AC line filter
or plug the powered mixer into a differ-
ent AC circuit.
•
Is there an external processor or other
electronic device connected to the
powered mixer? Make sure it is plugged
into the same AC circuit as the powered
mixer to reduce the possibility of creat-
ing a ground loop.
•
Refer to “Grounding” in Appendix B.
There’s sound in the monitors even though
all the channel MONitor controls are turned
down!
•
Make sure the
EFX TO MON
control is
turned down. This control adds the “wet”
effects signal to the monitor output even
when there is no monitor signal present.
Repair
Service for the PPM Series Powered Mixers
is available only from one of our authorized do-
mestic service stations or at the factory, located
in sunny Woodinville, Washington. Service for
Mackie Powered Mixers living outside the
United States can be obtained through local
dealers or distributors.
If your powered mixer needs service, follow
these instructions:
1. Review the preceding troubleshooting
suggestions. Please.
2. Call Tech Support at 1-800-258-6883, 8am
to 5pm PST, to explain the problem and
request an RA (Return Authorization)
number. Have your powered mixer’s serial
number ready.
You must have an RA
number before you can obtain service at
the factory or an authorized service center.
3. Keep this owner’s manual. We don’t need it
to repair the powered mixer.
4. Pack the powered mixer in its original
package, including endcaps and box. This
is
very important
. When you call for the
RA number, please let Tech Support know
if you need new packaging.
Mackie is not
responsible for any damage that occurs
due to non-factory packaging.
5. Include a legible note stating your name,
shipping address (no P.O. boxes), daytime
phone number, RA number, and a detailed
description of the problem, including how
we can duplicate it.
Summary of Contents for 406M
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