Subwoofer caught fire while in standby?!!

[X400]

Ok so i was sitting in my living room watching tv, my receiver was turned off

all of a sudden i hear a loud Pop! sound.... like when you throw christmas lights on the ground and they explode

then i hear some buzzing noises, then another Pop! bzz bz pop

so i was like wtf? it sounded like the back of my tv was blowing up

i walk towards it and i notice the ports on my subwoofer smoking!

smells a little like those cap guns with the lil strips of gun powder?


so i unplug the subs amp asap (its plugged into a surge protector btw)
i leave my sub in stand-by mode (thats probably relevant)


i unscrew the amp and take it out (mind u the amp and the sub are not hot)

when i take off the amp A LOT of smoke comes billowing out


Im still not sure where it started but the amp and sub look fine...

still haven't checked em out im waaay too tired but i thought id post this first and get some thoughts anyhow




its a Creative Sounds SD12 Subwoofer and a Elemental Designs LT350 amp

 

[mike c]

Elemental Designs LT350 amp

you should email ED.

is it still under warranty?

basically, they need to replace it.

smoke doesn't appear out of nowhere

 

[Haoleb]

almost sounds like one of your filter capacitors blew up or something, although... you would most definetly notice that. Post some pics Not that we can help you fix it, Thats up to ED. I just want to see the carnage

 

[mike c]

i've seen amp blowout pics before at the ED thread at avs ...

yeah, it was one of the caps

 

[TLS Guy]

Ok so i was sitting in my living room watching tv, my receiver was turned off

all of a sudden i hear a loud Pop! sound.... like when you throw christmas lights on the ground and they explode

then i hear some buzzing noises, then another Pop! bzz bz pop

so i was like wtf? it sounded like the back of my tv was blowing up

i walk towards it and i notice the ports on my subwoofer smoking!

smells a little like those cap guns with the lil strips of gun powder?


so i unplug the subs amp asap (its plugged into a surge protector btw)
i leave my sub in stand-by mode (thats probably relevant)


i unscrew the amp and take it out (mind u the amp and the sub are not hot)

when i take off the amp A LOT of smoke comes billowing out


Im still not sure where it started but the amp and sub look fine...

still haven't checked em out im waaay too tired but i thought id post this first and get some thoughts anyhow




its a Creative Sounds SD12 Subwoofer and a Elemental Designs LT350 amp

It sounds to me as if somehow, the amp managed to come on and push the DC rail voltage through the sub and fry the voice coil. It makes a lot of smoke when that happens and accounts for the loud pop.

Do not plug anything in. Whatever it is, it is serious and hazardous.

Start checking things by moving the woofer cone in and out and see if you can feel some grating. If you can there is gap rub.

Now connect an ohm meter to the woofer. See if the coil is open circuit, or if the DC coil resistance is below the specified DC resistance of 3.6 ohms.

If there is rub, open circuit or lowered resistance of the voice coil, then the voice coil of the woofer if fried and it will need reconing.

Now the amp. Take the cover of the amp and see if you can see any burnt components, and or blown fuses. If you can the unit needs professional service, or recycling.

If there is no obvious burn inside, take the unit to a competent service technician, and have him start the unit up slowly on a Variac, and watching closely what happens, especially for signs of DC offset.

This is a dangerous situation so do not plug the amp back in without professional assistance.

Unfortunately your story makes me suspicious you have lost the driver and the amp.

 

[GlocksRock]

I had the plate amp in my Dayton 12" sub fry itself while in standby mode once, it happened about 4 in the morning and I was woken up by the dog barking... the sub was also plugged into a surge protector at the time. Luckily it was still under warranty, and Parts Express took care of everything, and even reimbursed me for what I paid to ship the amp to them.

 

[TLS Guy]

I had the plate amp in my Dayton 12" sub fry itself while in standby mode once, it happened about 4 in the morning and I was woken up by the dog barking... the sub was also plugged into a surge protector at the time. Luckily it was still under warranty, and Parts Express took care of everything, and even reimbursed me for what I paid to ship the amp to them.

I did some surfing last night and this problem does not seem to confined to one brand or model. I did notice it seemed to afflict cheaper amps and subs.

I regard this a serious, and I think needs to be taken into consideration when purchasing these units. Probably they should not be left in standby, especially when leaving home.

Have any other members had this problem? This is the first post I have seen on these forums. We now have two cases of a first hand experience, and that is two too many!

 

[X400]

Thanks for the reply guys, has me pretty worried about what could have happened if no one was around when it happened :/

It sounds to me as if somehow, the amp managed to come on and push the DC rail voltage through the sub and fry the voice coil. It makes a lot of smoke when that happens and accounts for the loud pop.

Do not plug anything in. Whatever it is, it is serious and hazardous.

Start checking things by moving the woofer cone in and out and see if you can feel some grating. If you can there is gap rub.

Now connect an ohm meter to the woofer. See if the coil is open circuit, or if the DC coil resistance is below the specified DC resistance of 3.6 ohms.

If there is rub, open circuit or lowered resistance of the voice coil, then the voice coil of the woofer if fried and it will need reconing.

Now the amp. Take the cover of the amp and see if you can see any burnt components, and or blown fuses. If you can the unit needs professional service, or recycling.

If there is no obvious burn inside, take the unit to a competent service technician, and have him start the unit up slowly on a Variac, and watching closely what happens, especially for signs of DC offset.

This is a dangerous situation so do not plug the amp back in without professional assistance.

Unfortunately your story makes me suspicious you have lost the driver and the amp.

thanks! ill be sure to try that out, was thinking of contacting the underwriters labs as well.

Sigh aside from the shock of what could have been, now im disappointed about maybe having a bassless holidays

 

[GlocksRock]

Luckily the driver in my unit wasn't damaged, but the only gripe I had when I got my replacement amp is that the wires weren't long enough to connect to the sub, unless the amp was fully in the unit, in which case you can't get your hand inside to connect the wires... so I had to cut and solder on some extra wire inbetween to make it long enough. I don't think it would kill them to add a few more inches of wire.

I should probably just sell the sub and use the subs built into my BP7006 towers until I can afford something better... but money is kinda tight right now, otherwise I might end up getting a PB10NSD.

 

[highfigh]

smoke doesn't appear out of nowhere

Yeah, it does. That's why they refer to someone "letting the magic smoke out of the wires".

 

[mtrycrafts]

... but the only gripe I had when I got my replacement amp is that the wires weren't long enough to connect to the sub, unless the amp was fully in the unit, in which case you can't get your hand inside to connect the wires... so I had to cut and solder on some extra wire inbetween to make it long enough. I don't think it would kill them to add a few more inches of wire.
....

With such short wires, I wonder how can they assemble it as you have to attach wires with one of the components out of the cabinet, be it the amp or driver. Unless they use nano tech guys to do the assembly afterwards

 

[highfigh]

I did some surfing last night and this problem does not seem to confined to one brand or model. I did notice it seemed to afflict cheaper amps and subs.

I regard this a serious, and I think needs to be taken into consideration when purchasing these units. Probably they should not be left in standby, especially when leaving home.

Have any other members had this problem? This is the first post I have seen on these forums. We now have two cases of a first hand experience, and that is two too many!

Did you find any that were more problematic than others? It would be good to nail it down to one factory or design(er). I'd hate to read that anyone loses everything because of this, or worse.

 

[GlocksRock]

With such short wires, I wonder how can they assemble it as you have to attach wires with one of the components out of the cabinet, be it the amp or driver. Unless they use nano tech guys to do the assembly afterwards

I was wondering the same thing, but I think the wires on the original plate amp were a tad bit longer. The only thing I can think of is they put the amp and sub in before they finished building the cabinet.

 

[highfigh]

I was wondering the same thing, but I think the wires on the original plate amp were a tad bit longer. The only thing I can think of is they put the amp and sub in before they finished building the cabinet.

Sometimes, the woofer can be tipped into the opening to connect the wires. Needle nose pliers work, too.

 

[j_garcia]

Sounds exactly like what happened to my friend's JBL sub. It was a known issue with those amps and the amp manufacturer actually went out of business. At least nothing else suffered as a result of the issue.

 

[TLS Guy]

This thread needs to become a sticky, so we can keep tabs, on a problem I was not aware of before. It does not surprise me in a way, as I have often wondered if those, cut to the bone switching power supplies, in those class D plate amps were not bad news. This may well be a lot bigger problem than we realize.

I guess if you have plate amps with those type of power supplies in your sub, pull the plug before leaving home and going to bed.

House fires really spoil your day.

One other point; you would think that a thread marked, "subwoofer caught fire in stand by," would get peoples attention. It got mine right away. Yet despite the large amount of traffic in these forums, there have only been 124 views! The human instinct for self preservation, I would have thought would have led to upwards of 1000 hits by now. Human beings never cease to amaze me.

 

[Haoleb]

Yeah, the thread is a bit underwhelming, When you say your sub catches on fire, It had better catch on fire complete with pictures!! I know that the 99 dollar KLH sub (ASW 10-120) I used to have was kind of notorious for "catching on fire" I read stories all the time of people woken up by loud pops or humm coming from their subs, or subs dying from all kinds of brands.

 

[TLS Guy]

Yeah, the thread is a bit underwhelming, When you say your sub catches on fire, It had better catch on fire complete with pictures!! I know that the 99 dollar KLH sub (ASW 10-120) I used to have was kind of notorious for "catching on fire" I read stories all the time of people woken up by loud pops or humm coming from their subs, or subs dying from all kinds of brands.

Yes, but the OP was in the immediate area of the event. It might have been different is he had been asleep in bed, or out of the house. I don't have much regard for electronics, that produces that much smoke.

 

[highfigh]

This thread needs to become a sticky, so we can keep tabs, on a problem I was not aware of before. It does not surprise me in a way, as I have often wondered if those, cut to the bone switching power supplies, in those class D plate amps were not bad news. This may well be a lot bigger problem than we realize.

I guess if you have plate amps with those type of power supplies in your sub, pull the plug before leaving home and going to bed.

House fires really spoil your day.

One other point; you would think that a thread marked, "subwoofer caught fire in stand by," would get peoples attention. It got mine right away. Yet despite the large amount of traffic in these forums, there have only been 124 views! The human instinct for self preservation, I would have thought would have led to upwards of 1000 hits by now. Human beings never cease to amaze me.

I was thinking we could start a folder for equipment that has known issues, and categorize them as speakers, amps/receivers, CD/DVD, processor, etc and make that sticky. However, your observation makes me think it may not have the desired effect. Good idea, though.

 

[GlocksRock]

My sub/amp didn't actually catch on fire, but you could definitely smell that something was getting fried, and the sub was making a loud buzzing noise. Had it happened during the day when nobody was home, who knows what could have happened. Luckily everything turned out alright and I was only without a sub for a short period of time, and it was in my bedroom system which doesn't get all that much use anyway.