Mackie M2000, M3000, M4000

Owner’s Manual

Appendix A: Service Information

• Is the SHORT [4] LED lit? Turn the POWER off,

check the speaker connections and make sure that

there are no strands of wire shorting across the

speaker terminals.

• Is the OVER TEMP [5] LED lit? Make sure there is

cool air available at the rear of the ampliﬁer. Make

sure there is room at the front of the ampliﬁer for

warm air to exit. Allow the ampliﬁer to cool off.

• Is the PROTECT [3] LED lit? The power trans-

former may have overheated and shut down the

ampliﬁer. Turn the ampliﬁer off and wait until

the transformer cools down (it could take several

hours).

• Are there fuses in the speaker or in-line fuses in the

speaker wire? Check ’em to see if they’re blown.

• Make sure the speakers are working properly.

One side is way louder than the other!

• Do the ampliﬁer’s meters [2] read the same on both

sides? If not, your source signal may be delivering

an out-of-balance stereo signal.

• Are both Gain [1] knobs set to the same position?

• Are the speaker(s) impedances matched?

• Try swapping 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 speakers or speaker cabling. If the other side

is louder now, the problem is with the mixer, the

amp, or the line-level cabling.

The stereo music sounds kind of sideways,

and the bass frequencies diminish when

standing center, but get louder as you ap-

proach one side!

• Check the polarity of the speaker cable connec-

tions. You may have your positive and negative con-

nections reversed at one end of one speaker cable.

As soon as the music gets loud, the amp

shuts down!

• Check the ampliﬁer’s meters [2]. Be sure that OL is

not lighting up frequently or continuously.

• Can the amp breathe? The M-Series ampliﬁer draws

its ventilation air in from the rear and out through

the front. It needs plenty of fresh air to stay cool.

Do not block the ventilation ports.

• Is the SHORT [4] LED lit? If so, you’ve got a dead

short somewhere in your speaker setup, or the total

impedance of the load is too low. Turn the amp off

and rectify that right away.

Warranty Service

Details concerning Warranty Service are spelled out in

the Warranty section on page 27.

If you think your M-Series ampliﬁer has a problem,

please do everything you can to conﬁrm it before calling

for service. Doing so might save you from the depriva-

tion of your ampliﬁer and the associated suffering.

These may sound obvious to you, but here are some

things you can check. Read on.

Troubleshooting

No Power

• Our favorite question: Is it plugged in? Make sure

the AC outlet is live (check with a tester or lamp).

• Our next favorite question: Is the POWER [6]

switch on? If not, try turning it on.

• Is the light in the power switch illuminated? If not,

make sure the AC outlet is live. If so, refer to “No

Sound” below.

• The AC line breaker on the rear panel has popped.

To reset the breaker, turn the power switch off,

push in the button on the breaker, and turn the

power switch back on.

If the breaker pops again, disconnect the speakers

from the ampliﬁer and repeat the above procedure.

If the breaker pops again, there may be a problem

with the ampliﬁer. Refer to “Repair” on the next

page to ﬁnd out how to proceed.

No sound!

• Are the Gain [1] controls turned all the way down?

Slowly turn them up and see if you hear anything.

• Is the signal source turned up? Make sure the

signal level from the mixing console (or whatever

device immediately precedes the ampliﬁer) is high

enough to produce sound in the ampliﬁer. The SIG

LEDs [2] should be blinking to indicate that signal

is present.

• If the speakers are wired for BRIDGE mode, make

sure the AMP MODE [8] switch is set to BRIDGE.

• Is the X-OVER [11] switch set to LPF? If so, you are

only getting the lowest frequencies (below 150 Hz)

through the speakers. Set the X-OVER switch to the

FULL position to verify sound is present.