MACKIE THUMP TH-12A NO SOUND - Mackie TH-15A Active DJ Powered THUMP Speaker Stand and Cable Set TH-15ASET1

Your best bet is to contact Mackie Tech Support. Here is a link to their Suppot page. Mackie Tech Support
it's likely it needs to go to a repair shop. Here is a link to their service center finder. Mackie Service Center Locater

Whether you are experienced in electronics repair?
if not, try this simply way:
1: Test whether the power amplifier is still working. See figure 1.
Power OFF,adjust the EQ settings as shown in the picture.
Minimize LEVEL.Switch ON Power. Touch pin 3 at the INPUT socket by using a small screwdriver or piece of wire / cable.
Slowly raise the LEVEL,a little bit only (as the clock showed 7-8) until
sound is heard in speaker. If not heard, slowly raise again LEVEL.
If audio input signal is heard,it can simply be taken to mean
that the amplifier is working.
If LEVEL at 9 o'clock position,and the audio is not heard,
the possibility of the amplifier is damaged.
Switch OFF the power. Take it to a repair place.


2: When the Power LED is lit, but no sound,
There are many possible causes, one of which is:
I have been getting 3 times similar cases, and all are caused by
two Rectifier-Diode (either or both.) damage on the power-supply-unit.
Remove/desolder,measure, if damaged replace it with a new one.
See figure 2-3.




Hope it helps. Regards.

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"How to replace bass driver in mackie thump 15a".
Did you mean,disassembly the speaker enclosure?
Just remove the 16 screws at the rear cabinet, using a screwdriver.
Then remove the 4 screws that secure the speaker, using the hex key. Is the bass driver blown up / broke?

Jose Miguel Carcamo Cruces do you have pictures of these j112 fet ? Thank you!

Could be the crossover has died or the main speaker winding has failed. Open her up and connect on side of the main speaker direct to a 9v battery and then wipe the other wire over the other terminal. If you get a crackling from the speaker then it's likely the crossover, if there is no response at all from the speaker then it is dead and possibly the crossover too.

Remove 115V jumper in the Power Supply Unit at secondary side in order to operate Mackie TH-15A Speaker on 230V. Download Schematic Diagram from the below website:
https://elektrotanya.com/mackie_thump_th-15a_sch.pdf/download.html#dl https://elektrotanya.com/mackie_thump_th-15a_sch.pdf/download.html#dl

short circuit in secundary of the power supply or power amps damaged.

Make sure ALL interconnected equipment is powered from the SAME receptacle. Use extension cord if necessaary. Use ONLY balanced interconnecting audio lines as well. You have a ground loop... make sure all power connections are three wire.

Crackling is usally one or two things my guess would be bad grounding of the amp or bad connection with the jacks or plug it self try to make it crackle on purpose by jiggling the jacks see if it has any effect on the crackling try to narrow your possibilitys

The internal amp is in need of repair. Are there any other symptoms or signs?