BillFitzmaurice.info

Tom Smit wrote: ↑Thu Mar 27, 2025 9:26 pm

Seth wrote: ↑Thu Mar 27, 2025 7:33 pm That seems so weird. Not that I'm a electronics buff at all, but I've really gotta stretch my imagination to even begin to hypothesize how something like a short in the coil could cause the noise. Wow. Better call in Agents Mulder and Skully from The X-Files to investigate.

I am wondering if the coil was an on again/off again short, which reacted with the cap, causing an oscillation at the right frequency, while reacting with the amp. Just throwing darts.

That's the best explanation I've heard. I hope PE gets the coil out today so that I can get that thing fixed and back in the trailer.

Took the coil off the crossover and this is what I found underneath....
Couldn't see the burn until I took it off.

Decided to build a new low pass board and separate it from the other one......plus the size of the coil was different and wouldn't line up with the zip tie holes of the old one.

Anyway, got it wired up and buttoned up. Tested it - no noise. Ran music and it's fine. Swapped it to the monitor amp so that it could run full range and still good. Gonna' leave some music running through it for a couple of hours just to make sure everything's ok.

At this point, looks like the problem is solved.

Participation trophies will be awarded to all that showed up and opined. Thanks fellas.

Cause unknown. But, I'm just going to chalk it up to you really giving 'em the beans... Atta boy!

Overpowering for sure.

I wonder if the other three show burns in the wood too. And if that's a weak link in the system, would it be worth investigating an upgraded component?

That coil is 18 gauge wire. The driver voice coil is perhaps 30 gauge. I'm surprised the voice coil didn't fail before the inductor did. The problem with the capacitor may have had something to do with the coil overheating.

Bill Fitzmaurice wrote: ↑Tue Apr 01, 2025 3:41 pm That coil is 18 gauge wire. The driver voice coil is perhaps 30 gauge. I'm surprised the voice coil didn't fail before the inductor did. The problem with the capacitor may have had something to do with the coil overheating.

With these boxes being 14 years old.....I'm not surprised there would be an issue now and then. I do baby 'em a bit. Pretty much staying within the same volume limits since the beginning. And honestly, it would have been way easier to diagnose a blown driver.....plus I have two brand new spares that have been sitting on a shelf for 14 years. Along with two 3012LF spares for the subs....still haven't blown one of those either.

I'm not complaining. These boxes have been great for a long time.