Making the Best Out of the Situation

[Umbra]

I recently bought two 12" subs in a sealed enclosure and a two channel, bridgable amp, which I believe puts out around 175W (I'd guess bridged - I don't really know, I have thread opened in the amp section regarding that). It's junky, but I got it for $30. Money's tight. One sub, a JBL DVC 4ohm 550W?, has a bad coil, one reads 4ohms, the other 1ohm. The other sub, a Dual SVC 8ohm 550W also has a bad coil, It reads 6.5ohms.

Right now I've only hooked up the one coil on the JBL and bridged the two channels. I was recommended to set up the second as a passive resistor, so it's just mounted, but unwired. The problem is it rattles, deteriorating the sound quality. I believe it's coil rub:

What's the cheapest way to improve the system? I'd dissassemble the passive sub if necessary.

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[phemps 10+ year member]

wait wuuttt. Are you trying to say that you only have one of the coils hooked up, or you only have one sub hooked up and a blown one that your trying to use as a passive radiator?

 

[jrdnhsnbrg 10+ year member]

wait wuuttt. Are you trying to say that you only have one of the coils hooked up, or you only have one sub hooked up and a blown one that your trying to use as a passive radiator?

Sounds to me like OP has the one good coil of the one sub hooked up (which itself is a REALLY bad idea) and is trying to use the blown sub as a passive radiator.

OP, you reaaally shouldn't just have 1 coil hooked up. If I were you I'd try and sell the system and break even or maybe even pull a small profit and save up for a small system in the future. Sorry to say it, but otherwise you're SOL.

 

[hispls 5,000+ posts]

OMG. That sounds like the most ghetto system imaginable.

Ideally, pull one sub and cover the hole with some thick plywood or MDF and run whichever sub actually functions. Passive radiator requires careful tuning of the mass to function properly and is not simply a half blown sub. If you really don't care, take half a pound of lead shot and mix it with some glue or PL adhesive and smear it evenly around the center of the "PR" cone. Add more shot/glue mixture as needed to adjust tuning lower.

 

[Umbra]

As far as hooking up the one coil goes, I know it sounds iffy, but I haven't found anything solid that says it shouldn't be done. I hooked it up like that at bbeljefe's suggestion. I don't know what kind of reputation they have around here, but they're a "Supporting Vendor" and he's got a green name and some sort of trophy adjacent to it, so I thought I'd give it a try.

Yeah, it's certainly ghetto. I don't care too much about the PR sub. Do I start with its normal mass, I do I take it apart first?

Would it be better if I just cut the box in half and created a box for just the one sub?

 

[bubbagumper6 5,000+ posts]

There's really no reason as to why you can't run that sub with only one coil. It's certainly not ideal but it won't hurt it.

If the coil is rubbing on the other I would suggest taking the motor off so you're left with just a basket and cone but you would probably be better off just removing it and sealing the hole...

Again, none of this is ideal but I understand what it's like to just make the most of what you have.

 

---------- Post added at 01:59 PM ---------- Previous post was at 01:59 PM ----------

 

Would it be better if I just cut the box in half and created a box for just the one sub?

Yes. I've done this in the past. It won't look pretty when you're done but that's probably your best option as far as getting any kind of sound quality.

 

[des343 10+ year member]

Dude no just get rid of that crap in wait until you can actually afford something go on Craigslist you can get something actually works for cheap

 

[Falcons 5,000+ posts]

The best thing to do is take it out, create a bon fire with it and then invite a whole bunch of people and drink the night away.