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I have a few dB Technologies M12-4 powered speakers with the same problem, which leads me to believe it's a design flaw. The sound is intermittent. When I press on the right side of the amp, the sound comes back. I've checked the components and solder points on the transistors, connectors, etc, but can't find the problem. Any ideas or info I may not have? Thanks, Gene

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It still sounds like a bad soldering joint or connection somewhere!
You may have to resolder all the joints just to find it. Also look at the PC board for hairline cracks in the tracks. You might need a magnifying glass for this. The only other thing I can think of is you might be acting as an earth link when you press on it.

Posted on May 06, 2010

Testimonial: "Thanks a lot for your time and expertise! I've re-soldered many of the joints, but will follow your advice and check everything else out with a good magnifier. I was also thinking it could be a grounding problem. With the same problem happening with more than one unit, I was hoping that maybe it was a common problem that was known with this particular cabinet. Again, thanks for your time! Gene "

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Generally speaking, an amp attempts to protect itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

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Shorting out? If they short out they will never run again.

Generally speaking, an amp attempts to protect itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

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Try it on outlets that don't have any problems. If THAT works get the L/R outlets looked at by a trained electrician.

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Hi r these good speakers?


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what this means is that the speakers are designed for a car stereo alone, NOT stock stereo as it wont have enough power. See the one 50w x 4 ,, yeah its designed for those. All and all its not a bad deal.

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