Amp/sub advise? Trouble shooting?

[Pooter]

Not sure why but my wifes car keeps killing subs.
Combo is a single 12" alpine SWS-1243D(300w rms wired at 2ohms), and a Kenwood KAC-6104D amp.(600w, 300w @ 2ohms)
It will work fine for 3-4 weeks then there goes the sub again.
Any where to start troubleshooting? Its fairly easy putting a sub in a Infinity FX35 since its prewired in the cargo area from the factory sub, so hookups are fine.

Tired of messing with this thing
EW you on here yet?

[EW]

Not sure why but my wifes car keeps killing subs.
Combo is a single 12" alpine SWS-1243D(300w rms wired at 2ohms), and a Kenwood KAC-6104D amp.(600w, 300w @ 2ohms)
It will work fine for 3-4 weeks then there goes the sub again.
Any where to start troubleshooting? Its fairly easy putting a sub in a Infinity FX35 since its prewired in the cargo area from the factory sub, so hookups are fine.

Tired of messing with this thing
EW you on here yet?

Is the woofer in an enclosure? sealed or ported?
Is the gain on the amp all the way up?

[Pooter]

Is the woofer in an enclosure? sealed or ported?
Is the gain on the amp all the way up?

Sealed, and the gain is set mid range. The odd thing is it will sound clean/fine for 3-4 weeks before having a problem. I cant tell if possibly the amp is under powered? or some other issue?



Im just trying to figure out whats going on, I cant keep tossing subs at it....
I thought the first one had gone out just because it was pretty old and had been worked hard in the past, but now this one.

[LS1Goat]

You may be experiencing a grounding issue or are using a sub with a speaker that is either impedance mismatched or not rated for the peak power threshold of the amp.

[Pooter]

You may be experiencing a grounding issue or are using a sub with a speaker that is either impedance mismatched or not rated for the peak power threshold of the amp.

But it wouldnt have worked fine for 3-4 weeks if it was a ground issue right?

As for the impedance, im not really sure, I dont know that much about that.
The FXs already have a factory sub in the rear, basically all you need to do(based on what other FX owners have done from the forums) is clip the factory connector for your input, amp turn on, and ground the ground wire in the harness. Its just weird it would work and then stop, but like you said if the sub is being pushed to hard/out of the operating range, it makes sense....

[Hmbre97]

What's happening to the sub? You ever tore one apart to see what is going wrong?

And did you run a dedicated power wire and ground for the amp?

[Pooter]

What's happening to the sub? You ever tore one apart to see what is going wrong?

And did you run a dedicated power wire and ground for the amp?

The first sub had little plastic/resin flakes in the bottom of the box(maybe the cone separating?) The second one still looks fine, and no shavings/damaged parts I can see so far just looking it over.


Yeah, ran 8 guage power/ground, direct from battery, good ground, just used the factory amp turn on wire(which is getting the required 12v). Just cant figure why it would work fine for several weeks then go out, I would think it would surface right away and sound bad/not work

[jluv]

Sounds like she is getting a little too happy with the volume knob.

[Pooter]

Sounds like she is getting a little too happy with the volume knob.

Nah, she doesnt turn it up too much, not enough to keep blowing it so quickly. Im just trying to figure out if theres something wrong with my combo? on paper or otherwise?

[ThreeFingerPete]

Bring it over. I'll take a look at it for ya.

[rz5.0]

what r u using for the audio input on the amp.

[Pooter]

what r u using for the audio input on the amp.

The factory input wires for the factory sub. Its wired up the connector harness that comes with the amp(you could use it or RCAs for input)

[BP]

If you haven't already I'd turn up the LPF knob up a little and turn off the bass expander switch. Being a sealed encloser I doubt it's subsonic frequencies killing them but I guess it's possible. I'd also measure the impedance at the speaker terminals on the amplifier while moving the wires around, you could have an intermittent connection on one of the voice coils. Just thinking if the impedance jumps from 2-4 ohms randomly and one voicecoil just completely stops working then comes back on it could be part of the problem.

[rz5.0]

try running a RCA (low level) converter instead.

[Pooter]

If you haven't already I'd turn up the LPF knob up a little and turn off the bass expander switch. Being a sealed encloser I doubt it's subsonic frequencies killing them but I guess it's possible. I'd also measure the impedance at the speaker terminals on the amplifier while moving the wires around, you could have an intermittent connection on one of the voice coils. Just thinking if the impedance jumps from 2-4 ohms randomly and one voicecoil just completely stops working then comes back on it could be part of the problem.

Ill give it a shot, I was just trying to troubleshoot before I put another sub in it so I dont blow another one. Just cant figure out why it sounds just fine for a while then goes out, thats whats bugging me more than anything

try running a RCA (low level) converter instead.

I think im going to give that a shot next time too, the factory wiring that I spliced into is already high level, but at this point ill try switching it to low level with a line out converter.