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sub problem

D

Dunbar21

CEG'er
Joined
Dec 25, 2006
Messages
47
Does anyone know what would cause a sub to make like a loud backfire when the ignition is shut off?


Also my subs performance is weak. I had the same set up in my hatch Mustang and it sounded great but as soon as I put it in the Contour it doesn't put out hardly any sound. I know there a big difference between having it in an open hatch and in a trunk but I didnt think it would change that much.
 
Ok. If you can provide a bit more info I betcha you can find plenty of guys to help out.

Where is your amp currently grounded?

Do you have your subs pushed up against your seat? I find that I get MUCH improved sound by performing this simple little task.

How many watts is your amp? both peak/rms

How many watts are your subs? both peak/rms

What gauge wire are you using? both power/ground

Haha I hate to be so demanding, sorry :crazy:

EDIT: I've mentioned this before: Before I reconfigured my ground wires, I had loud kickback in my subs because my ground was insufficient. This is the main reason why I ask where your amp is grounded. It might make a difference.
 
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usually when you have a kick back when the ignition is off then that means you have a bad ground. check to see if the ground is solid metal not paint, tight oon the lug and no nicks in the wire. Also Check to see if the subs are pushed back as far as it can go only if the amp is not mounted on back of the subs. Or i hate to say it but from the kick back your subs couldve blew. Thats how mine blew. The amp puts on it's max power in one huge surge and can blew ur subs instantly. You can tell this by turning up the subs a tab bit and if it doesnt hit harder then the are blown. Also check the fuses on the amp. If you have a bad ground then most likely the amp couldve blew a fuse and causeing the amp to hit soft. If you replace it and it blows again re-ground it ASAP or your amp will fry.
 
I think you can use a resistor if I remember correctly to filter out the spike on turn off, or you can use a thing called a hitch hiker to filter out as well. The Hitch Hiker has a dial to tune in voltages, but you can set it to 12v and put it in line to filter it......

What is your remote turn on wire hooked to????
 
My amp is currently grounded to the top of my rear deck lid.

Yes the one sub is pushed against my seat.

The amp in a 4 channel sony xplode and i know its 500w max im not sure about rms tho

The sub is 500w max as well

Im using 8 gauge wire for both power and ground
 
yes i know thats my first problem and its just bridged down to 2 channels. Its only powering one sub. I'm debating on wether to pick up another one or just save up a lil more and buy a better amp/sub combo.
 
You're only pushing 250w max, and maybe 100w rms if you're lucky. You need to get a new amp ASAP. You're amp would be GREAT for someone who has really nice speakers and no sub. You could fetch some decent money for it. This is where you need to start.
 
On subs:

Interesting discovery - mount your subs with the cones facing the rear of the trunk (back of car) and pressed against the back of the rear seat. Wire 180 degrees out of phase. The sound wave will "bounce" off the back of the trunk and enter the cabin with the receeding woofer cone. It is a natural amplifier good for near 3db.

If your sub is in good working order, reverse the polarity on the speaker leads. I had mine reversed on initial install and the bass was bland. Reversed, and suddenly it came to life. Quick and simple test.
 
D13 how would one go about doing this?

And I'm getting new subs and a better amp this weekend so we'll see if this can hold me over for now.
 
Rear deck lid?

Rear deck lid?

Make sure you have the ground to the car body. Rear deck lid to me means trunk, not good ground. Rear deck (under window) should be OK.
 
where would be a good ground. I just drilled a hole in the deck under the rear window.
 
Well like I have said before, I grounded my amp awhile ago under one of the torx screws for my trunk latch. This was when I was an amateur at setting up amp+sub systems. Once I got it working properly I did not move my ground, I left it there haha. It works fine for me, except that I have two ground wires, one under each side of the washer to balance it out.

0505071236.jpg

Sorry about the poor image quality, I just love using my cell phone to take all of my pictures haha.
 
Dunbar21 said:
D13 how would one go about doing this?

And I'm getting new subs and a better amp this weekend so we'll see if this can hold me over for now.
Click to expand...

Easy way to test. Turn on your system and play something you know has a good bass line. Sit and listen for a few seconds. Open the trunk and go to the wire posts on your sub box. Reverse the leads - positive to negative and negative to positive. Shut the trunk and listen for a few seconds. Go and reverse the leads again - positive to positive and negative to negative.

Now, which ever wiring pattern gave you the most full and accurate sounding bass is the proper phase for your woofer.

Imagine each speaker as a piston. They all need to compress at the same time. If one is receeding while the others are compressing it will absorb the sound within that frequency.
 
cheap audio equipment causes feedback usually.

the good stuff doesnt.

In my experience, when you have subs firing toward the back, it sounds the best, cause the bass is "bouncing" off your trunk.

D13 I think I tried that one time and my sub refused to play if I remember right.

and subs are usually marked pos and neg.....
 
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Okay, so I got a amp today from a buddy of mine. Some 1600watt power acoustik. Only problem is one channel is blown. Is there anyway to replace a channel?
 
Dunbar21 said:
Okay, so I got a amp today from a buddy of mine. Some 1600watt power acoustik. Only problem is one channel is blown. Is there anyway to replace a channel?
Click to expand...

You may be able to compare the insides with this site.... http://ampguts.realmofexcursion.com/ then maybe fix it from there... best bet would be having it sent to a service center or taking it to someone who knows electronics very well...
 
Dunbar21 said:
Some 1600watt power acoustik....
Click to expand...

No need to replace the channel unless you are going to be using subs of such a high power as that. Use the only channel you have. It will push half that, so 800w. My amp is 800w and i have it turned up only about 3/4 and it POUNDS. My side mirrors shake. You don't necessarily need to waste your time fixing the other channel.
 
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