Trouble with amp, Maybe i'm an idiot

[thedemonhatesme]

I just picked up a rockford fosgate power puch 12 in subwoofer and a "esx" 800/2 amp from a buddy that used to be in his car. When i went to hook up the amp everything worked fine for about 1/2 hr and then i started to get smoke from it. shut everything down, opened the amp... couldn't find any burn marks, no leaky capacitors, I'm posistive i hooked it up right Positive to positive, neg to neg, remote to remote, bridged to mono block. There is one setting on the amp, i've never encountered before... there was a dial for the input that ranged from 600 ohm to 40 Kohm... what would that be for? I have it set to 600 ohm right now... any help would be great

thxs
josh

 

[Circuit]

Is the sub a DVC or SVC subwoofer? What is the impedance of the voice coil(s)? You could have smoked the amp if your subwoofer presented too low of an ohm load with the amp bridged. I don't know about that ohm rating knob, could be an incorrectly labeled gain knob? Is there a regular gain knob on the amp?

 

[chuyler1]

I'm not familiar with that input dial either but I suspect your sub was probably a 4ohm DVC and when hooking that up to a 2-channel amp bridged, will produce a 1ohm load per channel. This may work for a few minutes but the longer you listen at full volume the hotter the amp will get until eventually it will fry itself.

 

[thedemonhatesme]

The label beneith the knob is labeled input impodence, and again it ranged from 600 ohm to 40Kohm... It also has an input gain which ranged from 9v to .15v i have it set to the center which is .40v... i'm usually okay with this stuff.. this time im lost

 

[rx7_drifter_]

What model number is your sub and amp? How did you wire them together?

 

[thedemonhatesme]

The subwoofer is a 2 ohm sub made by rockford fosgate model number is: RFR3112 and the amp is a ESX 800/2 amplifier, any time i attempt to look up anything on the amp, its in german... i have the amp bridged as the diagram on the amp shows, i have the voice coils connected like the diagram on rockford fosgate's website says and im using 10 gauge wire between the voice coils and to run to the amp connection. I have 4 gauge wire from the amp to my capacitor and 4 gauge for my ground as well ( I used the jbl wiring kit for up 1000w capacity). The settings on the amp are set to low pass, 40 hz, bass boost is set to 0, and the left and right channel settings range from 0 degrees to 180 degrees( both set to 90 degrees)... hope this explains it rx7_drifter... im at a loss, when the amp starting smoking, i had been running at 3/4 volume for about 10 min.

 

[chuyler1]

Which way did you wire the voice coils? Parallel or Series?

Before you answer that, please look at this link:
http://mobile.jlaudio.com/support_pages.php?page_id=161

After you read it you will see that your subwoofer is either wired for 4ohms or wired for 1ohm. A 1 ohm load would explain why your amp isn't working...it would have fried itself by running each channel at 1/2 ohm when it is only rated for 2 ohms.

 

[thedemonhatesme]

wow... it all makes sense now...lol...i wired it in parralel... i'm going to switch and wire in a series and see the results... wow, let me see if this makes a difference, if it doesn't, i'll get more help from you guys, THANK YOU

 

[fourthmeal]

Problem is, once you let the magic smoke out of the electronics, it doesn't go back in. 99% chance that you fried the power supply, and there is a short or an open in the wound power supply.

Or in other words, that s*** is fried because you went too low in impedance for too long.

 

[chuyler1]

Or in other words, that s*** is fried because you went too low in impedance for too long.

Bingo. If you verified it was wired in parallel the amp is toast. I don't think swapping it at this point will do you much good. Most amps have protection circuits to prevent this sort of thing but if you smelled smoke...that's never a good sign.

 

[thedemonhatesme]

I agree, i know i prolly toasted the amp, but when you get it for 20 bucks, no complaints, its just getting another one...lol... I took the entire amp apart and found no burn marks of the board or any of the surrounding metal, can't exactly locate where the smoke came from. Im going to give it one last run. The only thing is finding a place to be able to tune the amp at a decent volume that the neighbors don't complain... the speaker was loud, really loud...

 

[fourthmeal]

I agree, i know i prolly toasted the amp, but when you get it for 20 bucks, no complaints, its just getting another one...lol... I took the entire amp apart and found no burn marks of the board or any of the surrounding metal, can't exactly locate where the smoke came from. Im going to give it one last run. The only thing is finding a place to be able to tune the amp at a decent volume that the neighbors don't complain... the speaker was loud, really loud...

The damage is likely exactly where I told you. You won't be able to easily see it. The likely spot is the wound transformer that looks like a mile of thin wire all coated nicely. Great chances are that this transformer's wire is now shorted together.