Appendix A: Service Information

If you think your Mackie product 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.mackie.com) to get some ideas or contact our technical support heroes. You may find the answer to the problem without having to send your Mackie product away.

4.Replace the fuse drawer by pushing it all the way back into the IEC socket.

If two fuses blow in a row, then something is very wrong. Try a different outlet in a totally different location. If fuses continue to blow, see the “Repair” section on the next page to find out what to do.

Troubleshooting

No Power

Our favorite question: Is it plugged in?

Make sure the line cord is securely seated in the line cord socket and plugged all the way into the AC outlet.

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

Is the POWER switch in the ON position?

Are the power LEDs on the front and rear panel illuminated? If not, make sure the AC outlet is live. If so, refer to “No Sound” below.

If the power LEDs are not illuminated, and you are certain that the AC outlet is live, it is possible the fuse has blown.

No Sound

Are the power LEDs on the front and rear panel illuminated?

Is the LEVEL control turned up?

Is the signal source turned up? Make sure the signal level from the mixing console (or whatever device immediately precedes the loudspeaker) is high enough to produce sound.

If it’s a stereo pair, try switching them around.

For example, if a left speaker is presumed dead, switch the left and right cords at the speakers. If the problem switches sides, it’s not the TH-12A. It could be a bad cable, or no signal from the mixer.

To remove and replace the fuse:

1.Disconnect the power cord from the IEC socket.

2.Remove the fuse drawer by prying it open with a small screwdriver. It will slide all the way out.

FUSE

3.Remove the fuse and replace it with an equivalent-type fuse.

115 VAC unit: 6.3 amp slo-blo (T6.3AL/250 V)

230 VAC unit: 3.15 amp slo-blo (T3.15AL/250 V)

Bad Sound

Is the input connector plugged completely into the INPUT jack?

Is something connected to the THRU jack? Try unplugging it. If the sound improves, whatever was plugged into the THRU jack may have affected the signal.

Is it loud and distorted? Reduce the signal level at the mixer.

If possible, listen to the signal source with headphones plugged into the preamp stage. If it sounds bad there, it’s not the loudspeaker.

Too much bass or not enough bass? Move around the room and see if the bass response changes. It’s possible your listening position coincides with a room mode where the

low frequencies either become exaggerated or nulled. If so, try moving the loudspeakers to a different position, or moving your listening position.

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