Destroyed sub in 3 minutes why??

[AJStaples]

Like 10 years ago I bought 2 Polk DB1040DVC subs. They are 50-270w rms.
They've been sitting new in box since I never got around to buying an amp or whatever. I ponied up a couple dollars and at crutchfields recommendation, grabbed a pioneer GM-DX874 4/3/2 ch amp.

I connected front door speakers (kicker k5 6x8) to channel A
I bridged the sub on channel B.
I wired the sub in parallel for a 2 ohm load (amp says it can handle)
I only want to do 1 sub.
I wired it just like the amp book says.
Everything seems compatible as far as wattage and impedance.

I finished the job, went to a location I could turn the volume up a bit to tune it up. I drove like 3 miles and the sub just stopped pumping.

I took it out after I got home, I was sure that maybe one of the connections in the sealed box popped off or something, but when I took the sub out, a cloud of dust and stink followed. The woofer was fully depressed, and basically melted.

What did I do wrong? I have another sub to replace it with, but I obviously don't want to **** that one up too. Could the frequency be to low or gain to high?? What should I set these at for these subs.

Btw, the door speakers sound great and have no issues.

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[AJStaples]

Dumb question... I'm sure I can Google, but does bridging 2 ohm make 1 ohm? Should I have wired the sub in series for 8 ohm then bridged at amp? Idk... As the question might be obvious I don't have a good grasp on some of this stuff

 

[hispls 5,000+ posts]

What did I do wrong?

You put too much power into it.

 

[AJStaples]

You put too much power into it.

...yes I figured that was likely the answer... But do you think it's the amp itself or could I have had the gain to high? Idk. The amp specs say it does only 250 rms on bridge to 2ohm load.
The sub is rated up to 270 rms, max 540. I think they are compatible products. I'm hesitant to put the other sub in, fearing I'll just blow it.

 

[hispls 5,000+ posts]

The sub is rated up to 270 rms, max 540. I think they are compatible products. I'm hesitant to put the other sub in, fearing I'll just blow it.

None of those published power numbers should be taken as law. Speaker companies usually inflate and the more reputable amp brands under rate. It really is as simple as you gave them too much power, and if you blew those up so quickly you're obviously not going to be happy with the output so you had better pick something that can hold a bit more power before seizing up since I'd guess you'll be trying to push them hard.

 

[AJStaples]

None of those published power numbers should be taken as law. Speaker companies usually inflate and the more reputable amp brands under rate. It really is as simple as you gave them too much power, and if you blew those up so quickly you're obviously not going to be happy with the output so you had better pick something that can hold a bit more power before seizing up since I'd guess you'll be trying to push them hard.

So do you think that this kicker sub will do the job? Wired same way to the amp?

 

[1aespinoza 10+ year member]

...yes I figured that was likely the answer... But do you think it's the amp itself or could I have had the gain to high? Idk. The amp specs say it does only 250 rms on bridge to 2ohm load.
The sub is rated up to 270 rms, max 540. I think they are compatible products. I'm hesitant to put the other sub in, fearing I'll just blow it.

Amp and sub are perfectly compatible. Sub is 270 rms while amp is 300 rms @4ohms. Amp is CTA-2006 compliant so all ratings are true. It has 2 30 amp fuses which make it roughly 600 watts rms total power. What I find odd is that amp has more power @4ohms than 2ohms. I wonder if that is a typo.
Anyways, turn down the gain, set switch to LPF, set FREQ to about 80. Now turn on radio to the loudest you will most likely listen to. With a bass heavy song, turn gain up until sub distorts, then dial back a bit or until you are comfortable with the bass output.
This is assuming you have four rcas going into the amp. It is a rare occurrence but not unique. I believe your coil came loose and lodged at the bottom. No movement plus power= melted coil.
Also make sure your box is within manufacturer specifications.

 

[1aespinoza 10+ year member]

So do you think that this kicker sub will do the job? Wired same way to the amp?

That sub will work great as well. Wired in series to 4ohms or each coil to it's own channel. Parallel is 1ohm so not optimal for your amp.

 

[AJStaples]

Amp and sub are perfectly compatible. Sub is 270 rms while amp is 300 rms @4ohms. Amp is CTA-2006 compliant so all ratings are true. It has 2 30 amp fuses which make it roughly 600 watts rms total power. What I find odd is that amp has more power @4ohms than 2ohms. I wonder if that is a typo.
Anyways, turn down the gain, set switch to LPF, set FREQ to about 80. Now turn on radio to the loudest you will most likely listen to. With a bass heavy song, turn gain up until sub distorts, then dial back a bit or until you are comfortable with the bass output.
This is assuming you have four rcas going into the amp. It is a rare occurrence but not unique. I believe your coil came loose and lodged at the bottom. No movement plus power= melted coil.
Also make sure your box is within manufacturer specifications.

I have a set of rca wires going to amp for front speakers, and another set going to amp for sub.
The box is .75 cu. It's a prefab box. Manufacture recommend .66 cu. I figure a touch larger is ok, let's sub breath more.
I assume ur right about the coil. I had to "peel' it up to lift the woofer... But it just retracts back in. Do I set the amp to 2 ch or 4 ch? I feel like when I set it at 4 ch that the sub didn't do anything. I think the manual says to set it to 4ch if doing 3/4 ch... Not sure.
I will try the other Polk db10 that I have. I really hope I don't mess it up though. Lol.
Thx for ur help.

 

[shredder2]

The box is .75 cu. It's a prefab box. Manufacture recommend .66 cu. I figure a touch larger is ok, let's sub breath more.
I assume ur right about the coil. I had to "peel' it up to lift the woofer... But it just retracts back in.

Sounds like you slinkied the coil.
Maybe set ur levels right with the other one?.. the prefab is another concern. U might be playing a touch under tuning at volume... 3 min?... clip city for sure and those low notes did not help. Bet it sounded great until...

 

[1aespinoza 10+ year member]

I really hope I don't mess it up though.

You should be ok. 2 channel is when using only one set of rcas. Box size is ok as well

 

[AJStaples]

Sounds like you slinkied the coil.
Maybe set ur levels right with the other one?.. the prefab is another concern. U might be playing a touch under tuning at volume... 3 min?... clip city for sure and those low notes did not help. Bet it sounded great until...

It was to quick to hear Any clipping. It just sounded good until it sounded like nothing. Lol. Should prob tune it til it sounds good then dial it back I guess.

 

[shredder2]

I'd beware of trying to get louder by increasing gain wired 2 ohm to get output + Its a sealed box? (ya ...I finally read your 1st post) I bet your turning it up where possible to get loud. Rise/enclosure is killing your output... especially sealed and its a single 10?
I had a set of Polk Db 10's previously and ported in 2ft3 with 25in2 of port tuned 33hz they did not blow out my windshield but were musical and got fairly loud on 1000w (Rf bd1000)... I'd say port it and and set levels/filters right... its only a single 200w 10 sub after all...

 

[AJStaples]

It's a truck, so I got limited space. It's not the prettiest set up, but it fits good behind the console on the floor in the back. No way to fit a ported box rly. Ya it's just a single 10

 

[hispls 5,000+ posts]

So do you think that this kicker sub will do the job? Wired same way to the amp?

For a little more money you might look at the Dayton lineup over at Partsexpress:

Home

Dayton Audio RSS265HF-4 10" Reference HF Subwoofer 4 OhmAs with the rest of the Reference Series, the main focus of the Dayton Audio RSS265HF 10" subwoofer is ultra-low distortion. Second, third, and intermodulation distortion are kept extremely low by utilizing three short-circuit paths within...

www.parts-express.com

Something like this should perform well in a sealed box and would hold up better to some abuse at your power level.
They've got a decent looking shallow mount too but that may be hit or miss surviving if you've got a heavy hand on the volume knob.