# melted wires and subs not working



## tiFreak (Apr 12, 2012)

A few weeks ago I pulled my car out of storage for the winter, since I have been driving a car with no subs all winter I immediately cranked up the volume as I was driving home. About halfway home (about 2 minutes) my subs suddenly stopped working. Once I was home I used a Power Probe to verify that I had power, ground and signal going to my amp and I found that the 40a fuse on the amp was blown. I replaced it and tried my subs again and one sounded like it was blown and the other had almost no excursion and was really quiet.

I went to check my wiring and I noticed that my wires and my terminal cup to the sub that sounded blown was partially melted. I checked my power and ground wires, I was able to check about 90% of the power wire and it all looked good but my ground wire was loose in its crimp connection. I fixed the ground wire and disconnected the sub with the melted wires and tried it again but the other sub still has no excursion and I noticed the power light on my amp flickering every time the bass hit.

Could the loose ground have caused all the problems I'm having now? And since fixing the ground didn't make the problems go away could I have damaged my subs or amp? I'd really appreciate any help.


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## minbari (Mar 3, 2011)

1) how much power?
2) what gauge speaker wire?
3) ohm out each sub, what does it say?

if you have too small gauge wire it will get hot and cause what you saw. also if the sub VC shorted out, it will have drawn alot more current and if your speaker wire was not a large enough gauge then it will melt too.


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## Z-Roc (Mar 22, 2012)

need bigger wire


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## MarkZ (Dec 5, 2005)

Um...yeah...doubt it.

Something broke. This doesn't happen under normal operation. Two possibilities immediately come to mind. 

1) As minbari said, your VC is toast and the amplifier was delivering lots of current. This would be slightly surprising. If this happened, your amp is a champ. Or it toasted too. 

2) Something is wrong with the speaker connection, causing heat to develop near the terminal cup.

My vote is #2.

But you're right to suspect the ground too. Minbari's advice to check resistances of the load (including the terminal cup) is a good start.


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## tiFreak (Apr 12, 2012)

minbari said:


> 1) how much power?
> 2) what gauge speaker wire?
> 3) ohm out each sub, what does it say?
> 
> if you have too small gauge wire it will get hot and cause what you saw. also if the sub VC shorted out, it will have drawn alot more current and if your speaker wire was not a large enough gauge then it will melt too.


2 subs getting 250W at 2 ohms (they're 4 ohm DVC subs wired to 2 ohms)
I believe the gauge is 14 (can't remember but I measured it with a ruler and it was about 2mm)
by ohm out you mean check it with a multimeter? I'll have to do that tomorrow since I don't own one



MarkZ said:


> Um...yeah...doubt it.
> 
> Something broke. This doesn't happen under normal operation. Two possibilities immediately come to mind.
> 
> ...


I don't know if it was the connection because I had this setup working great for 2 years.

is there any way to test the amp? I've seen videos but it's usually with some bench testing set up using a battery and a speaker.

I'm planning on reusing the box so I'm just going to run the speaker wires through a hole and seal it up seeing as the terminal cup seemed to be the weak link


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## MarkZ (Dec 5, 2005)

Connections loosen or become corrosive over time. You can run the speaker wires directly to the speakers, or you could buy a better quality terminal cup and perhaps use better quality terminals? They're fairly cheap these days online.

But yes, definitely test speaker resistance before using them again.


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## tiFreak (Apr 12, 2012)

the way I see it, it's just one less thing to go wrong, plus on my box the terminals came just glued in and I don't really feel like trying to force it out



minbari said:


> 3) ohm out each sub, what does it say?


borrowed my boss' multimeter today and tested the resistance

subwoofer #1 (the one with barely any excursion)
one voice coil was at about 1.5 ohms, the other was around 1 ohm

subwoofer #2 (the one that sounded blown and melted its terminal cup)
both voice coils were between 3.5 and 4 ohms

both terminal cups had about 2 ohms at each wire

both subs passed the 9 volt battery test

I also opened my amp up and I didn't see any signs of burning or water damage


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## tiFreak (Apr 12, 2012)

sorry that I haven't been on in a while, I had to get my track car ready for an event on short notice so my stereo got put on the back burner for a while

I replaced the one sub that was showing low resistance and I have my box all back together with 12 gauge speaker wire run through holes in the box. I'm letting the JB Weld that I sealed the holes with dry and I'll try it again tomorrow. I'll update this thread with the results


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## tiFreak (Apr 12, 2012)

got everything hooked back up and so far it seems like it's working great. thanks to everyone who offered suggestions, hopefully this thread will help someone else out.


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