Why did my voice coil fry?

[bmk6795 10+ year member]

Ok I have a hdc 3 15 D2 wired to 1 ohm on an ab vfl 4480. Setup worked great for a couple weeks. Amp had a bad cap, I replaced the cap last night, put the amp back in the car and do a short test, everything was good. This morning on my drive to work I put on a song, turn volume to 25, about 15-20 SECONDS later I hear a pop and my **** is full of that God awful smoke. Any ideas to why? I'm stumped.

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[los33 10+ year member]

You installed the cap incorrect? Maybe left to much solder on the board.

 

[bmk6795 10+ year member]

You installed the cap incorrect? Maybe left to much solder on the board.

Well, I put the positive cap post into the hole marked positive. There was a very small amount of solder left around the hole for the negative post, but a very small amount.

 

[shauncox26]

if one cap was bad several others may have been going bad. so when u put a fresh one in the one working good made the other/others go. kinda like rebuilding a motor u can rebuild the top or bottom half; and soon the opposite u rebuilt will poop on ya cause the other rebuilt half works as was intended. thus causes more strain on the older parts ad they have wear and the new doesn't. if u blow a Mosfet u replace the whole input or output side to assure all ur mosfets are on the same playing field.

 

[garychurch84 10+ year member]

if one cap was bad several others may have been going bad. so when u put a fresh one in the one working good made the other/others go. kinda like rebuilding a motor u can rebuild the top or bottom half; and soon the opposite u rebuilt will poop on ya cause the other rebuilt half works as was intended. thus causes more strain on the older parts ad they have wear and the new doesn't. if u blow a Mosfet u replace the whole input or output side to assure all ur mosfets are on the same playing field.

I agree with this 100%.....if one component failed you can bet almost everytime other components were stressed as well!

 

[bmk6795 10+ year member]

if one cap was bad several others may have been going bad. so when u put a fresh one in the one working good made the other/others go. kinda like rebuilding a motor u can rebuild the top or bottom half; and soon the opposite u rebuilt will poop on ya cause the other rebuilt half works as was intended. thus causes more strain on the older parts ad they have wear and the new doesn't. if u blow a Mosfet u replace the whole input or output side to assure all ur mosfets are on the same playing field.

Well, there are only 2 caps. The other sill looks good, can't say that it is for sure, same with the mosfets. But even if the other cap went out how would that fry my sub? And I rebuilt my head about 30k miles ago and my block is still running strong

 

[bmk6795 10+ year member]

And right now the amp still powers on, gonna see if I have output when I get home.

 

[shauncox26]

well ur heads are only part of the top end. u still have cams rockers and push rods. and dont believe for a second that that new head doesn't cause more strain. my father is and has been a mechanic for 50+ yrs and it's rule number one. the mosfet part was just a for instance. as for the other cap there is a expression i believe it's dont judge a book by its cover. have u checked to make sure that ur amp didn't go poof that it is infact the sub. does it sound like a slinky when u press in on the cone? is the cone froze up? i almost bet it's not the sub u Proly fried the amp.

 

[bmk6795 10+ year member]

well ur heads are only part of the top end. u still have cams rockers and push rods. and dont believe for a second that that new head doesn't cause more strain. my father is and has been a mechanic for 50+ yrs and it's rule number one. the mosfet part was just a for instance. as for the other cap there is a expression i believe it's dont judge a book by its cover. have u checked to make sure that ur amp didn't go poof that it is infact the sub. does it sound like a slinky when u press in on the cone? is the cone froze up? i almost bet it's not the sub u Proly fried the amp.

The smoke was coming out of the box, the sub was hotter than its ever been when I felt it, but like I said I'm gonna test everything when I get home, hopefully get some more info and figure this out

 

---------- Post added at 12:35 PM ---------- Previous post was at 12:34 PM ----------

 

And I believe you about new parts putting strain on older parts, I was just saying.

 

[bmk6795 10+ year member]

well ur heads are only part of the top end. u still have cams rockers and push rods. and dont believe for a second that that new head doesn't cause more strain. my father is and has been a mechanic for 50+ yrs and it's rule number one. the mosfet part was just a for instance. as for the other cap there is a expression i believe it's dont judge a book by its cover. have u checked to make sure that ur amp didn't go poof that it is infact the sub. does it sound like a slinky when u press in on the cone? is the cone froze up? i almost bet it's not the sub u Proly fried the amp.

I wish you were right about it being the amp. But like I said I know what voice coil smells like.

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Now I just gotta figure out how this **** happened.

 

[bmk6795 10+ year member]

As of now the amp stills powers on, gonna test it on my girls alpine when she gets home. Kinda scared to though, don't wanna **** up her subs too.

 

[shauncox26]

got **** u charcoaled that mofo. did u put a Maxwell super cap in there **** it. i would be to scared to try it on ur girls subs. u dont have a little **** sub to try it on. barrow a buddies kicker or something.

 

[garychurch84 10+ year member]

fixing the cap still doesn't mean something else wasnt fucked on the output section of the amp!!!

 

[joom 10+ year member]

Before you try the alpine check for DC voltage across speaker terminals.

 

[bmk6795 10+ year member]

got **** u charcoaled that mofo. did u put a Maxwell super cap in there **** it. i would be to scared to try it on ur girls subs. u dont have a little **** sub to try it on. barrow a buddies kicker or something.

Yeah I didn't test it on them, I'm scared to, lol.

 

---------- Post added at 07:10 PM ---------- Previous post was at 07:10 PM ----------

 

Yeah I didn't test it on them, I'm scared to, lol.

I did this as you're the second to recommend it and it kinda fluctuates between 45-55. Not sure what that means though