Mackie M1200/M1400 APPENDIX A Service Info, Warranty Service, Troubleshooting, No power, No sound

APPENDIX A: Service Info

WARRANTY SERVICE

Details concerning Warranty Service are spelled out on the Warranty Card included with your amplifier (if it’s missing, let us know and we’ll rush one to you).

If you think your amplifier has a problem, please do everything you can to confirm it be- fore calling for service, including reading through the following Troubleshooting section. Doing so might save you from the deprivation of your amplifier and the associated suffering.

Of all Mackie products returned for service (which is hardly any at all), roughly 50% are coded “CND” — Could Not Duplicate, which usually means the problem lay somewhere else in the system. These may sound obvious to you, but here are some things you can check:

TROUBLESHOOTING

•If the OUTPUT APPLICATION switch is set to SUBWOOFER , make sure the LOW CUT FILTER frequency control is set to OFF or nearly OFF. If it is turned up above the subwoofer cutoff frequency, then there will be no output from the amplifier.

•Is the SHORT 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 HOT TEMP STATUS LED lit? Make sure there is cool air available at the front of the amplifier. Make sure there is room at the sides of the amplifier for warm air to exit. Allow the amplifier to cool off.

•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.

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 switch on? If not, try turning it on.

•Is the green light next to the power switch illuminated? If not, make sure the AC outlet is live. If so, refer to “No Sound” below.

•The AC line fuse inside the cabinet is blown. This is not a user-serviceable part. Refer to “Repair” on the next page to find out how to proceed.

No sound!

•Are the GAIN 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 should be blinking to indicate that signal is present.

•If the speakers are wired for BRIDGE mode,

make sure the AMP MODE switch is set to BRIDGE .

One side is way louder than the other!

•Do the M•1200/M•1400’s meters read the same on both sides? If not, your source signal may be delivering an out- of-balance stereo signal.

•Are both GAIN knobs set to the same position?

•Are the speaker(s) impedances matched? (See Appendix E — “Do The Math: Ohms, Loads and Such.”)

•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 speak- ers 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 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.

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