Death Penalty 18s

[Jaker89 0]

Went to a local competition this weekend and have a few issues with the subs.

First off they are in a 12 cubic foot wall with 210 sq inches of port for burps. Amps hooked to them were 2 AQ 3500s strapped at .5 ohm rising to 1.9ohm clamped at 6500,

I went to burp at the show and did a 54.8 my first burp and a 55 my second burp. Decided to test door open about 10 minutes later burped for 3 seconds and did a 58. Went to try in the passenger kick panel door open and they started making a funny sound. Checked the impedence at the amps and its 1 ohm when it was .5 ohm a little bit earlier. Do you think I unwound a coil? The sub sounds funny so I unhooked the amps, but won't have time to pull the subs until next weekend.

If they fried on 7k then they won't be able to handle the 4 crescendo 2ks I am going to be using the rest of the year. Strapping 2 per sub. Are there power handling upgrades available.

The master amp was tuned with a dd-1 right before the show as well.

[Dangrebel 89]

They are 1500rms a piece...

[bassahaulic 155]

Only way to know is to pull them out and have a look.

[KyleBrown 121]

what's your voltage drop? rising to 1.9 means each amp is close to 1ohm. You should be doing more than 3500 per amp..... Unless these are the old ones?

Could have popped a lead too.

[ia2 21]

Like was said above, you should definitely pull them and have a look. It could be many different things, but worst case scenario a recone will fix it. If the coil is unwound I would almost bet something else broke first. Pull it out and maybe take some pics and we will help you the best we can.

[Jaker89 0]

How much do recones run a piece for them and where would I pay for them?

[Jaker89 0]

They are 1500rms a piece...

Yeah 1500 a piece daily(which that rating is under real world handling for sure). Usually can handle 3x-4x that for 3 second burps.

[Jaker89 0]

what's your voltage drop? rising to 1.9 means each amp is close to 1ohm. You should be doing more than 3500 per amp..... Unless these are the old ones?

Could have popped a lead too.

and yes they are the old AQ 3500s not the .1s

[ia2 21]

Give us a call Monday 256-417-6658 for pricing and we can take payment either over the phone or through PayPal.

[Jaker89 0]

It was coil rub on the bottom and the coil broke off the former. Im just gonna sell them and go with something else I think.

[95Honda 486]

lol. You broke 158 with a pair of 18s and roughly 3 times the rated thermal power and want to get rid of them now...

A recone(s) is going to be a fraction of the price of new sub(s).

[KyleBrown 121]

lol. You broke 158 with a pair of 18s and roughly 3 times the rated thermal power and want to get rid of them now...

A recone(s) is going to be a fraction of the price of new sub(s).

This.....

[Jaker89 0]

I didn't blow them is the thing. They broke at the former from "bottoming out" which if these are doing that at 40hz I want nothing to do with them. Also if they won't take 6500+ on 3-5 second burps for a pair then they aren't the sub that I want. They had maybe 10-15 burps on them tops when they went. I can't be buying recones every few weeks. They may be cheap at first, but after a few they get expensive. I am going to go with a brand that I know will handle the power.

[Dangrebel 89]

Why did you go with a 1500rms driver and now complaining about the power handling?

[95Honda 486]

If a sub bottoms out it is your fault. You will more than likely will end up breaking any sub you buy.

Good luck!

[ia2 21]

I'd still like to see pics. Something else gave way first before that sub bottomed out i can assure you. And the subwoofer is not the reason you are breaking stuff....this will continue to happen with any speaker you install....I'm not trying to convince you to keep running dp's if you aren't happy with them, but trying to get you to look deeper than just the surface to fix your problem.

[///M5 2,833]

The master amp was tuned with a dd-1 right before the show as well.

That is your first mistake right there. The second you can determine once you peak at the drivers.

[Aaron Clinton 2,372]

The master amp was tuned with a dd-1 right before the show as well.

That is your first mistake right there. The second you can determine once you peak at the drivers.

Not to say anything negative, but I have seen people say the same thing about setting their gains on a few forums now.

[95Honda 486]

^^That and the fact that a DD-1 (or any test equipment for that matter short of a servo system) will not keep you from mechanically damaging a driver...

[lee 2]

I didn't blow them is the thing. They broke at the former from "bottoming out" which if these are doing that at 40hz I want nothing to do with them. Also if they won't take 6500+ on 3-5 second burps for a pair then they aren't the sub that I want. They had maybe 10-15 burps on them tops when they went. I can't be buying recones every few weeks. They may be cheap at first, but after a few they get expensive. I am going to go with a brand that I know will handle the power.

Unfortunately, you are involved in SPL, which in and of itself forces you to test the limits of the equipment you use.

Once you break into the high 50's, you reach a point where the sub system, and sometimes vehicle expose weak links and fail. To touch 58 with the limited equipment you have, and not want to continue developing the combination ( which is rewarding you ) is beyond me.

At your current stage, most are doing in the field repairs after a few runs.

Now, going off of what you describe above, I would suggest shrinking the enclosure down.

[Jaker89 0]

I am running 2 AQ HDC3 18s on 7400 watts clamped. Taking burp after burp and not even getting hot. Burping 45hz and box is tuned at 44hz. Not having any issues with them and they are a 1000watt rms sub. Put 2500 clamped to the 2010 IA death penalty for multiple burps and it loved it. The new style clearly is not the same quality at all.

[Jaker89 0]

http://i441.photobuc...magejpeg_23.jpg

To everyone I have talked to it looks like interior damage from coil rock and rubbing. Outside of the coil is fine and where it was rubbing it did this to the motor.

http://i441.photobucket.com/albums/qq131/jaker89/imagejpeg_24.jpg

Edited July 23, 2012 by Pontiac Warden

[95Honda 486]

When the coil hits the backplate it gets distorted and will run into al these types of problems.

Also, for SPL you want high efficiency and the most flux you can get in the gap. This means a small gap with very tight, unforgiving tolerances. I have shimmed coils with 2 layers of manilla envelope on SPL subs...

In other words, clank! Your done... Nature of the beast...

[Jaker89 0]

Clearly by the pics you can see that it rubbed on the pole piece.

[Jaker89 0]

And what I am wondering. If the sub is not the issue then why is the other one working just fine still? Why are the other 2 sets of subs that I have tried doing just fine on the same thing?