Re: Mackie Thump TH-15A repair, no sound and OL LED always on, power supply, low qual

Power Amp not working; I went ahead and tested preamp including DSP, all good there. Swapped preamp section with my working amp and it worked there too.

So looks something on the main power amp board.

Re: Mackie Thump TH-15A repair, no sound and OL LED always on, power supply, low qual

I was able to get the +15v working replacing Q104. Replaced Q105, the caps and zener diodes for a exercise in soldering desolder I suppose since Q104 was the only bad part.

Still not working, power LED cycles from on to dim about every second. If I disconnect the output of the preamp from the input of the power amp, this stops.

I am thinking the next step is to inject a signal to the power amp with speakers connected and preamp disconnected to verify that it is working....

Re: Mackie Thump TH-15A repair, no sound and OL LED always on, power supply, low qual

Apologies for joining late on this subject, but it appears I have a Mackie Thump 15-A with the same issues as described in this post: +15v is out (even with preamp disconnected) and OL Light stays on with a hiss coming from speakers but no sound from input.

Background: Speaker was working connected to the right output of a Mackie mixer in my music practice room from Dec 2010 until Mar 2018. The speakers were used several times a week, never saw the road, and very rarely had the...

Re: New Members - please post your introductions here

Hello all, joined the forum because there seems to be some good information and knowledge sharing going on here. I am a software engineer by day and musician who does much of his own equipment repair. Was an electronic hobbyist in my younger days, still have a few tools and skills but definitely need a good magnifying glass now. Read schematics and have basic electronics knowledge. Hope to learn from y'all and contribute what I can.