blown sub!

mekanism

Well, like an idiot I blew one of my momo 12's. I just switched from the dx 12's and I wanted to see what the Momo's could do. So I cranked it up and all of a sudden one of the subs starts rattling. I just recently learned about the 40 hour break-in period, and had I known, I wouldnt have committed this stupid act. I'm running 2 C300.2's bridged for 550 Watts RMS per sub. With my previous systems I was usually underpowering the sub slightly so I never had to worry about blowing it; the subs would just distort then I new when to turn it down. Now even when I turn the system up about half way the sub rattles. I guess I will have to put the Dx's back in. Anyway, I have a question in all of this babbling. Is it possible to buy a new voice coil and fix the sub or do I need to buy a whole new one? Or can I send the sub in and have polk fix it? Any help is greatly appreciated

AustinKP

I don't think they're repairable, since I don't think polk sells parts, but you might be able to return them if they're still under warranty. Where did you buy them?

exalted512

you cannot repair them
is it under warranty?
if not, itll probably be cheaper just to buy a new one
you mightve cracked the spyder, which is impossible to fix on a MOMO
-Cody

mekanism

I pulled the sub out today and found that the spider was completely off of the platform. I looked at the voice coil and it looked fine so I epoxyed the spider back in place. Needless to say it didnt work. I let the epoxy set up for a few hours and then put the sub back in but it now sounds really crappy. I will just have to buy another one. I am considering swithching to two 10 inch instead of 12's. The 12's dont give me the real punchy base that I'm looking for. Thanks for all of the help!;)

mekanism

If I decide to stick with the 12's can I still order the older ones?

exalted512

nope
-Cody

mekanism

Well thats sucks! I guess I will just buy 2 10's and redesign my spare tire enclosure. I'm limited on space anyway. Are the new subs alot better than the old ones. I was pretty dissapointed with the momo 12's that were in there. They didnt hit nearly as hard as I was expecting for running 550 watts RMS per sub. I used to have 2 MTX 10's and a 300by2 also from mtx and I remember it hitting way harder and cleaner than the polk stuff.

exalted512

you had 2 momo 12s with 550 each and 2 mtx's with 300 watts each and the mtx's were louder?
theres something wrong if thats the case...
-Cody

mekanism

Maybe my filter settings arent right on my deck. I messed with the settings earlier today and I cant seem to get the sound where I want it. I can either get decent punchy bass without low freq. bass or real low freq. bass and virtually no punch, its weird. Im running an alpine 7392. I wish my deck had presets. Could this be a box volume problem? If so I will re-check my volume or add some poly-fill.

exalted512

unless your box is over 2 cubic ft i wouldnt *think* it would make the huge difference youre talking about
as long as its around .88ft^3 you should not be having much of a problem
are the gains on the amps low?
-Cody

mekanism

The gains are at about 3/4. Even when I turn them all the way up the subs still dont sound right. Its almost as if they arent keeping up with the song, like there is a delay. Its weird. Hopefully if I switch to 10's it will sound the way I want. I wont be able to switch for a while do to lack of funds.:(

exalted512

maybe its the amp?
have any friends that have an amp thatll do 500 watts at 4 ohms?
-Cody

AustinKP

You mentioned that the subs sounded weird, like they weren't keeping up. Have you tried inverting the phase to them? (switching the + and - connections)

mekanism

No I havent tried that yet. I tried to use my decks sub reverse feature but it didnt work. When the bass hits the speaker moves out instead of in. I will try switching tomorrow.

neomagus00

Originally posted by mekanism
When the bass hits the speaker moves out instead of in.

huh?

and i'm assuming you tried alpine's phase-reversal thingy, which does exactly the same thing as switching the wires, so if one doesn't work neither will the other.

mekanism

For some reason the phase reverse feature isnt working on my deck. The funny thing is that there isnt even a reference to it in the Alpine manual. I will just try switching the wires. When I hooked it up the positive from the amp went to the positive of the sub so I dont know whats up with this. I also made sure all of the rca's were correct as well. I will recheck all of the wiring when I get a chance just to make sure.

exalted512

move your ground while youre at it
make sure theres no paint--just bare metal
if youre using a screw, make sure its stainless and make sure youre using a lock washer on it
-Cody

LittleCar_w/12s

Screw Cody?

I have a 7/16" dia bolt for my ground
And those spiney electrical washers do a lot of good, but you have to crank em down real tight.

Bolt > flatwasher > ground lug > SpineyWahser > Car > LockWasher > Nut > Nut.

That seems to do it! (I could have welded it to the car easier...)

-Jerry

exalted512

ive used those electrical washers sometimes, but only when the screw keeps spinning
i dont want to use a bolt cuz i dont want to crawl underneathe the truck, i could use a seat belt bolt, but its too hard to get the paint off
a self tapping stainless steel screw with a lock washer seems to be the easiest way for my needs
-Cody

neomagus00

Originally posted by mekanism
For some reason the phase reverse feature isnt working on my deck.

it may be, a phase switch on subs is really really hard to hear. might as well try the wires anyways tho