Anyone Ever Had a Sub Blow Out by Power Failure?

[EdwardGein]

My building has recently had a bunch of short power surges because of some work by the Power company in our area. I have all my electrical equipment attached to a surge protector, yet recently, my Subwoofer blew, despite being connected to the surge protector, because apparently something called a capacitator, blew out as a result. I was fortunate that the Subwoofer manufacturer (Orb Audio) replaced it for me at no additional charge other then shipping. I had left the sub premanently powered on. Any advice as to how to avoid this in the future, or was this just a fluke. None of the other equipment attached to the surge protector was damaged I should note.

[kexodusc]

A power surge blew out a capacitor? In the sub's plate amp? Wow. That's some diagnosis. Did they tell you that? Was the sub being used? I'd believe the cap just failed as a more likely story. Only one capacitor fried, right?

I'd suggest using the "auto-on" feature if it has it. It would take some kind of power surge to blow up any components if the sub was off and not drawing any juice other than the miniscule standby amount. I'm not a big fan of those surge protectors, especially for plugging amps and subs into.

[Rock789]

most likely a voltage spike is what blew up the cap...
if voltage goes higer than the rating of the cap, it will arc across the plates and it will blow up... if it's an oil filled cap, it will have a nice fireball ;o)

an MOV on the other hand, which are in a lot of filter devices will create a nice fireball without the oil!

[Rock789]

never lost an amp (knock on wood) due to power outtages, but I have lost two wireless keyboards... toasted the computer side of the receiver/transmittrer...
I thought this was a bit odd since they both ran off regulated 5v dc... perhaps my computer powersupply doesn't do such a good job filtering...
nothing else in the computer has had problems yet...

[kexodusc]

Yeah, except most plate amps I've worked on have pretty robust caps. Do voltage surges go above 250V? Surprised it was only 1 cap.

[Rock789]

Yeah, except most plate amps I've worked on have pretty robust caps. Do voltage surges go above 250V? Surprised it was only 1 cap.

the peak of a normal 120VRMS signal is around 170V normally...
so having a peak voltage above 250V is possible, but since you pointed this out... more than just 1 cap would have failed most likely if there was a >250V spike...

most likely a bad cap as Kex said ;o)

[kexodusc]

the peak of a normal 120VRMS signal is around 170V normally...
so having a peak voltage above 250V is possible, but since you pointed this out... more than just 1 cap would have failed most likely if there was a >250V spike...

most likely a bad cap as Kex said ;o)

I could be wrong, I'm not an authority on this stuff that's for sure. Maybe there was a lower grade cap in the amp? Just surprised a surge would only fry a single cap. Where's an EE when you need one? :ciappa:

[EdwardGein]

I asked them what caused the problem & they said that the capacitor blew, whatever that is.
I'm assuming it was caused by the damn power outage bursts the damn utility company has been having recently. In this case, all of a sudden, the sub which wasn't being played at the time nor any of my electric devices) made this dying noise just as the power went out of my apartment for about 15 seconds. I didn't give it any thought & a few hours later when I turned the receiver on, nothing was coming out of the sub. I was under the impression the surge protector was suppose to protect all my stuff. Oddly, there were no problems with the rest of my equipment. Perhaps if I had left the power on the sub on automatic this wouldn't have happened & I'll do that in the future. About 10 years ago, I stupidly connected my computer directly into an outlet & one day the computer wouldn't work because it fried my hard drive. I should have gotten a new computer instead I spent $400 at the time for a new hard drive, what was I thinking!

[N. Abstentia]

What kind of surge protector are we talking here? It could be doing more harm than good.

[Rock789]

Where's an EE when you need one? :ciappa:
rofl...
me...lol

if it's a low cost amp, probably using low cost material from who knows where...
so the chance of having a cap below standards isn't odd...
guess it depends on what kind of testing the cap manufacturer performs... if they just spot check, there will always be some bad caps...

[Daedilus]

So called "surge suppressors" are actually more like "surge catchers".

They act in the same way as a seawall does to a big wave. A monstrous wave contains far too much power to be stopped dead by any practical construct, so the purpose isnt to stop it, but to knock the feet out from under it, electricaly speaking.

They allow the surge to pass but block a % of the power using seriesed capcitors or metal oxide varistors to absorb a quantity of the power as it flows over it. The resulting process of the pooling is a far less severe surge allowed to pass on to the equipment.

This process is different on a "Line Conditioner / UPS" which arrests incoming power, using it to charge batteries and isolating it from the actual power supply to your equipment...the easiest way to tell the difference is by looking at the pricetag. You will be hard pressed to find an actual UPS line conditioner for less than 500 bucks.

Surges are measured in Joules, which is a strange thing to measure them in, however because of the irregular nature of them, it is perhaps the most accurate way of measuring their strength.

One Joule is the amount of energy needed to exert a force of one newton for one meter...

wtf is that you ask? good question.. but who cares.

Real world equivalent is the force required to lift a small apple one meter against gravity.. or think of it as 4 calories, or the amount of energy you get from drinking a single drop of beer...

Suppression factor is usually around 1100 joules or so average, (or less than a quarter can of beer hahaha), So you are better off with the grandmothers solution of unplugging your devices when not in use, if you arent ready to drop some serious cheese on UPS lineconditioners.

Not really relevant, but related, so ill throw it in, a hella lot of people buy these things thinking it will protect them against lightning. they will not, in no uncertain terms, protect against lightning strikes. I worked in lightning protection and repair for several years, and have seen things that would curl your toenails... houses knocked flat on their foundations, missing walls, missing roofs, shattered foundations...the list goes on.

These devices are only made to stop, and only warrantied against MAN MADE surges. not lightning. No device or substance made by man can withstand the force of or stop a direct lightning stirke.

Case in point, Air is an excellent insulator, you can be just 3 feet away from a quarter of a million volts of man made electrical power and be perfectly safe, insulated by the air between you. Lightning arcs over 20 miles through open air hundreds of times a day and can pack voltages estimated at up to 200 million volts driven by over 10 million amperes, with a temperature 5 times hotter than the surface of the sun...

roughly one billion joules... enough to push that small apple over twice the distance from earth as the moon. (over 500,000 miles)

(the highest voltage man has ever generated is around 2 million volts at less than 1/10th of 1 amp)

folks, that vaporizes glass, rubber, ceramic, titanium, and Aunt Edna's tube amps all with equal ease. Your only defense against it is a good homeowners insurance policy.

[kexodusc]

Case in point, Air is an excellent insulator, you can be just 3 feet away from a quarter of a million volts of man made electrical power and be perfectly safe, insulated by the air between you. Lightning arcs over 20 miles through open air hundreds of times a day and can pack voltages estimated at up to 200 million volts driven by over 10 million amperes, with a temperature 5 times hotter than the surface of the sun...

roughly one billion joules... enough to push that small apple over twice the distance from earth as the moon. (over 500,000 miles)

(the highest voltage man has ever generated is around 2 million volts at less than 1/10th of 1 amp)

folks, that vaporizes glass, rubber, ceramic, titanium, and Aunt Edna's tube amps all with equal ease. Your only defense against it is a good homeowners insurance policy.

Wow. Lightning hit my house and only blew up (melted/exploded) a few roof tiles.
Guess I got lucky. That's it, I'm never golfing under dark clouds again.

[GMichael]

That's it, I'm never golfing under dark clouds again.

Good move. I don't know the actual numbers, but I remember reading somewhere that golfers get hit at a much higher rate than others.

We did have a 5 minute power outage a few weeks back. When the power went back on, my sub made a loud thump that scared the h.ll out of me.

[N. Abstentia]

Surge protectors are one of my pet peeves. Working in both the computer and home theater industries, I hear all the time "but I had everything connected to a surge protector" only to find a $7 WalMart power strip. Uhhhhh......no. Not even remotely close to being a surge protector.

[kexodusc]

Sub amps and even older power amps went through the initial voltage surges on power up all the time for years. They seemed quite capable of handling it without frying caps. Anyone with a BFD knows that if you shut it off and turn it back on while the sub is still on, the initial surge will register on the richter scale. That gets aweful scary when you're not expecting it. The woofers have no problem taking it (usually).

I don't use a surge protector. I've been lucky in my last 2 homes (in Maine and now NB, Canada) to be on extremely reliable grids. Few spikes, few drops. It's great. Back in Atlanta things were very different. The vacuum cleaner would dim the lights, your neighbor's clock radio could knock the grid off. Constant spikes frying systems at work.

I'm not even sold on the good surge protectors. Do they provide enough juice on demand, while also protecting against damage for a 500 watt- 1000 watt consumption typical home theater?

[Rock789]

the "thumping sub" would be a signal thru the audio circuits...
I'm guessing the cap which blew was in the powersupply circuit.

I have never researched more expensive surge suppressors, however, a properly sized UPS would have the capacity to run an entire audio system...
the issue here is... find a UPS with enough filtering after the inverter, or there may be noise in the power out...
if there is noise in power out, it is possible the power supply of each individual audio component to filter, but again, I do not know the specific powersupply circuits of all the individual audio components...

[EdwardGein]

I hate to say it as I feel totally embarassed but the surge protector I used & still use is a $400 Monster Reference PowerCenter HTS 3500 MKII that I got new from Amazon for $150 & am still using. I still don't understand how just the sub could go basically the way Rock789 described above & nothing else was affected. To better clarify what was happening because of the power company, was power would suddenly go off without warning for say 10-30 seconds & then burst back on. This had nothing to do with lightning, whatsoever. If I wanted to be a total hardass & waste my time, I'd have contacted Monster as they supposidly have some kind of guarantee but Orb Audio was gracious enough to replace the sub free other then shipping (to & back). I have renters insurance but that only kicks in after $500 worth of damage has occured & the sub was around $400 or so.

[Daedilus]

Wow. Lightning hit my house and only blew up (melted/exploded) a few roof tiles.
Guess I got lucky. That's it, I'm never golfing under dark clouds again.


Yeah, more than likely you got hit with a branch from a multiple discharge. The vast majority of lightning is branched multiple discharge strokes, the solitary arcing single bolt is less common, and far more powerful. When they occur, they hit the ground hard

I have seen a house totaled... yes totaled, like a car, by an insurance company :p one strike.

[kexodusc]

Yeah, more than likely you got hit with a branch from a multiple discharge. The vast majority of lightning is branched multiple discharge strokes, the solitary arcing single bolt is less common, and far more powerful. When they occur, they hit the ground hard

I have seen a house totaled... yes totaled, like a car, by an insurance company :p one strike.

So, what you're saying is if I could get hit by a solitary arcing bolt and harness that power - adding it to my own, I'd be INDESTRUCTIBLE!!!