Broken woofer - help!

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I'm going to apologize up front as I'm a total amateur and don't have a great grasp on all things PA/speakers.

I think I blew a speaker last night playing and need help diagnosing what I need to replace/fix. I have a Behringer Europort EPA900 PA system (portable) that comes with 2 passive 2-way speakers (I believe that is what they are called). These speakers each contain 10" woofer (4 OHM Woofer, 1000W Peak, 250W continous) and 1.35" aluminum-diaphragm compression driver.

I still get sound out of the top of the speaker (compression driver) but heard a muffled sound out of the woofer and now no sound. I removed the case and their doesn't appear to be any visible damage (torn cone, etc).

Tried to read around on the internet about what exactly the problem is and read some about coil maybe damage or possible crossover components gone bad. I just have no idea if the whole woofer needs replaced or what. Any help on diagnosis would be much appreciated.

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.
 
You'd want a pro repair shop, imo.

Someone may know of an equivalent speaker, but it would require the same basket size and very similar specs.

You can test the woofer separately, but you may find that you blew the amplifier not the speaker... or you blew the tweeter, not the woofer...

_-_-
 
So the other speaker works OK? If so, unplug that good speaker and connect it to the cord from the other channel. If the good speaker also sounds bad, then the amp has the problem. But if the good speaker still sounds good powered by the other channel, then your speaker has the problem.

A blown speaker usually looks just like a good one visually.

If you remove the wires from your woofer, you can measure resistance of its voice coil. That MAY tell us something.

As to troubleshooting, you have one working speaker. You can take the woofer out of it, and substitute it into the bad speaker. If it now sounds OK, that verifies the woofer is bad. If the good speaker now sounds like the "bad" one, then we suspect the crossover.

Most likely your woofer has blown.

If the woofer is blown, you can either replace it or have it reconed.
 
An Update...

Thanks for your responses. So I was able to get a hold of a brand new replacement woofer (exact same model) to test out. Had a friend with some pro audio experience help take it apart and connect it. Still no audio from the woofer but audio from the compression driver. He touched the end of the 1/4 in cable directly on the back of the crossover component where it sends out to the woofer and got sound out of the new woofer. So he tried it on the old woofer and it got sound too. The problem sounds like it is somewhere on the 2-way crossover.

My next question (sorry, total newbie) is how do I diagnose what to replace on the crossover? (somehow the compression driver is still getting sound) It looks to have 2 inductors, 3 capacitors and 2 resistors. Nothing looks obvious visually in terms of damage.

If the whole crossover must be replaced, how do I know what would be a valid replacement? I googled the part number and cannot find it anywhere and am not sure on the frequency, ohms, etc.

Thanks in advance.

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.
 
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He touched the end of the 1/4 in cable directly on the back of the crossover component where it sends out to the woofer and got sound out of the new woofer. So he tried it on the old woofer and it got sound too. The problem sounds like it is somewhere on the 2-way crossover.
Sounds like it could be a bad solder joint or a crack in the PCB track.
Visually checking the solder side of the board may show the problem.
If nothing stands out try resoldering the connections.
 
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Thanks for the suggestions. It appears that a continuity test shows the big inductor on the lower left of the pic and the capacitor at the top right both seem to have a problem. These test fine on my working speaker. How hard is it to replace those parts individually or do you pretty much have to replace the whole crossover?
 
I don't know what could possibly go wrong with those inductors, unless they were melted or the core was crushed. Gotta be a solder joint. They wouldn't even be that hard to rewind, if it came down to that. Caps and resistors aren't a problem to get a generic replacement. Again, I don't see any signs of stress - like the PCB being cooked around the resistors.
 
I've seen the inductor leads break, right where the lead goes through the circuit board, on those crossovers.

Sometimes, if you unsolder and remove the inductor coil from the circuit board, you can get hold of enough of the existing wire, to pull it out far enough to go back through the circuit board, and solder back to the original trace. Be sure to strip the insulation (scrape the epoxy from the copper).

If you can't get enough wire length that way, you'll need to take apart the other speaker, remove its corresponding inductor from the board, and measure it for value with an LCR meter. Then, you can get a replacement inductor of the same value for the one that's broken...

Regards,
Gordon.
 
That's a solder joint issue. If that's what's happening, pull the inductor and solder on a couple flexible leads onto the stubs that are too short to connect to the PCB reliably. Flip it over and re-zip-tie it to the PCB, and run the leads where they are supposed to go. It won't do it again.
 
I have almost similar issue with same crossover, and I'd like to say, it is not only bad solder joint issue (which happens because flux was not washed away and PCB is eaten). Resistors are also faulty - wire gets melted inside, so when you push it by hand, contact is restored momentarily. Furthermore, even capacitors fail, in my case 6uf capacitor one had short, and another one had high internal resistance! So I've replaced all capacitors and resistors on both crossover, just in case, and re-soldered all solder points.
 
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