Smoke Detectors set off by Sub?

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I just got a SVS PB12+2 which I have been wanting for several years and have just hooked it up to check basic functionality. I had the sub set for 20Hz setting. I was playing it a below conversation level and was watching the end of Underworld which had some low bass in it. About 11:00 pm my five connected smoke alarms (builder installed to code) went off about every 30-45 minutes for 5-10 minutes. I pulled the batteries out of the smoke alarms because that was the cause of the problem last time the smoke alarms went off. No help and no way to shut them off without trial and error on the circuit breakers. One night without sleep was the result. The next day I bought new batteries and put them in all the smoke detectors. The smoke detectors were silent all day but about 11:00 pm the smoke detectors started going off again in the same pattern. I had not used the subwoofer that day but it was plugged in on auto detection mode. My wife said the smoke detector problems coincided with the PB12+2 operations and that was the cause. I turned the power off to the subwoofer and third and following nights the smoke alarms were silent. I haven’t turned the sub back on yet because none of the family can afford another sleepless night. I am going to reset the sub to 25Hz setting and try to operate it again next Friday when I have a day off. If the smoke alarm fiasco repeats, that is probably the end of my using the subwoofer (I am outnumbered 3:1) unless I can have the smoke detectors replaced with some less sensitive model. I am using this sub in a great room with open floor plan of 8500 cu. ft. My question is has anyone else had an experience with their subwoofer setting off a smoke alarm or is this just a coincidental experience not related to the subwoofer. Does anyone know how smoke detectors are constructed to help make sense of this? Could vibration cause a smoke detector to go off?

 

[ParadigmDawg]

I am by far no expert here but I dont think it's the sub vibration causing this but more likely a drop in the electrical current.

 

[mazersteven]

Now thats a first.

 

[GlocksRock]

Have you contacted SVS to see if they have ever heard of this before? They have excellent customer service and should reply to your inquiry right away, or you could just call them.

 

[ParadigmDawg]

I just held my sub up to the ceiling and blasted it as loud as it would go right at the smoke detector and it didnt do anything. Maybe he has eartquake detectors and he thinks they are smoke detectors.

Steven, keep in mind when you smart off to me that my sub weighs 120lbs and my ceilings are 14 foot and I held it up there on a ladder with one hand. I am one bad dude!

 

[Halon451]

That's wacky. I can't see how even the pull of current that the sub is drawing would cause this to happen, especially if it's happening at moderate to low dB levels, and that sub isn't working it's a** off.

It could be pure coincidence. For it to set off ALL detectors leads me to believe that vibration is not the issue, since every detector in the house would not receive the same vibration and therefore probably not subject to the same effects. Of course I'm no smoke detector expert either.

Something tells me a faulty circuit in the house is the culprit more than anything, but it would require more troubleshooting and maybe a visit from a certified electrician.

 

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All the smoke detectors are wired together so if one goes off they all go off. I causes quite a loud piercing noise intended to wake everyone in the house up, and they do that quite well. I have not contacted SVS yet because I did not want to bother them with this issue if no one else has ever experienced it. It is starting to sound like this is a real odd occurance. I don't know if the smoke detectors are on the same circuit as the sub or not.

 

[GlocksRock]

Have you tried plugging the sub into a different outlet to see if it makes a difference.

 

[Exit]

I had not thought of the problem being electrical but plugging the sub into a different outlet is a good idea that I will try Feb. 1st. Any more suggestions are appreciated.

 

[Halon451]

I'd say it has to be an electrical issue in the house. Subs aren't supposed to cause things like this - unless there is maybe some strange internal fault in the sub's amp itself (maybe ). Have you ever plugged a vaccum cleaner into this particular outlet? Those things draw a hefty amount of current. Whether or not it might replicate the issue you're having is where this story takes it's bizarre turn.

Either way, keep us posted - I'm dying to know what it is at this point.

 

[ParadigmDawg]

Why are we waiting until Feb 1st?

 

[Rickster71]

How old are the detectors?
I had the same problem with my detectors, always going off in the middle of the night.
Once or twice a year; for the first five years, It would happen. I thought it was a low battery.
One possibility: If the heads weren't covered properly during the building process,(sanding, painting) they may have become contaminated with dust,etc.
The other is: They have a life span of only eight to ten years.
I changed all the heads in my house, and haven't had the problem since. (six years.)

 

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Just in the way of background, the house was bought new construction about 12 years ago and passed all inspections. There have been no modifications to the house electrical system. I am in St. Louis so I don't think the smoke detectors would have earthquake sensing in them. The A/V equipment is on one wall about 6 ft long with one double outlet. I have a Samsung 61" DLP, a PS3, a Yamaha 840W receiver, a DVD, a VCR, a Dish Satelite Receiver, a BFD and the 900W PB12+2 plugged into these outlets. So far no circuit breakers have tripped but I have not turned the volume up much past conversation level since adding the PB12+2. I am seriously considering taking the time to map out the circuit breakers if I can get my wife or kids to assist.

 

[Rickster71]

Here is a link to U.S. Fire Admin. site on smoke detectors.
http://www.usfa.dhs.gov/citizens/all_citizens/home_fire_prev/alarms/
An excerpt:
How Long will my Smoke Alarm Last?
Most alarms installed today have a life span of about 8-10 years. After this time, the entire unit should be replaced.
It is a good idea to write the date of purchase with a marker on the inside of your alarm so you will know when to replace it.
Some of the newer alarms already have the purchase date written inside.

 

[Rickster71]

Exit,
I can tell you in isn't related to your subwoofer; it was just coincidence.
I've installed and replaced hundreds of smoke detectors; the heads going off as you describe, is very common as they reach the end of their useful life.

Rick

 

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I am waiting for Feb 1st to experiment because I work 9 hour days and get every other Friday off, and Feb 1st is an off day. I will start Friday morning and if the problem repeats itself and we loose a couple nights sleep, we would still have Sunday night to recover before work/school. I will take the time this weekend to identify the smoke detector circuit(s) so I can shut them off if need be. Hopefully they are not on the same circuit as any of the kitchen appliances or furnace.

I operate on a little longer time scale than most so Feb 1st is comming up fast for me. I have been waiting to get the PB12+2 since the first reviews (in 2006 I think) and only did so because they were being discontinued and I thought this was my last chance to get a good double subwoofer (for 8500 cu ft) at a good price. It really is a great piece of gear and the maple finish is awesome. The day I ordered it they sold out of maple finish. Anyway I also bought the BFD a year ago while they were still available, in anticipation of getting the PB12+2 some time in the future. I need to find a day in the future when everyone is out of the house so I can run some sine waves and SPL measurements to calibrate the sub. Everyone in the family complains if I try to run sine waves.

Oh, thanks Rickster 71 for the info on changeout of the smoke detectors. I'd do that before giving up on the PB12+2.

 

[mtrycrafts]

I just got a SVS PB12+2 which I have been wanting for several years and have just hooked it up to check basic functionality. I had the sub set for 20Hz setting. I was playing it a below conversation level and was watching the end of Underworld which had some low bass in it. About 11:00 pm my five connected smoke alarms (builder installed to code) went off about every 30-45 minutes for 5-10 minutes. I pulled the batteries out of the smoke alarms because that was the cause of the problem last time the smoke alarms went off. QUOTE]

Let me see if I understand you problem. You played the sub at low levels, to 20Hz or lower. Then after you finished watching, before 11pm, the alarm came on at 11pm as you indicate the durations.

If so, this cannot be a sub issue.
You can check the theory of current by finding which 120V circuit it is on and throw the breaker and back on after a second. But, you'd have this issue after a power failure too. Has that happened in recent memory?

What is the batter in it for, back up? If new batteries didn't cure it, then your old ones didn't cause it either.

Most likely cause is one or several defective alarms since you indicate that when one goes off, they all do.

I had a similar condition in the middle of the night coming on for no reason but they are wired differently and only one went off. Replaced it and it is working as it should.

You need to either replace all five, or hunt down the culprit.

 

[Exit]

Update

I fired up the subwoofer yesterday for about six hours (including playing the Titan AE ice field scene) and no smoke alarms went off either during operation or afterward at night. It seems my problem is resolved.

As far as the subwoofer being the cause of the smoke detectors going off, I can offer the following. About the only thing different from the first incident was that I vacuum cleaned the smoke detectors, based on recommendations on some of the smoke alarm websites. (The smoke detectors showed no signs of being dusty but I couldn’t see inside.)

From reviews of the PB12+2 it was said that the PB12+2 could set things in the room (or other rooms) vibrating. This is conjecture, but it may be the PB12+2 stirred up dust in one or more of the smoke detectors and set off the alarm. The only thing that doesn’t make sense in this theory is that during the first incident the smoke detectors didn’t go off immediately, but went off at night. I had never had a false alarm with the smoke detectors until the PB12+2 operated. The smoke detectors also went off once at random during the following week for about two minutes (before cleaning).

The smoke detectors are about 12 years old and fire authorities recommend replacing them at seven to ten years, so my smoke detectors are probably near the end of their useful life and were making false alarms. Having old smoke detectors however does not explain the smoke detectors first going off with first use of the PB12+2. Whether smoke alarms sounding is caused by the PB12+2 or just a random coincidence remains a question.

Some other related data is that the smoke alarms are hard wired on their own circuit breaker and each have battery backup for power failures. A suitable replacement smoke detector is available on the web for $9.49 each. The hassle with smoke detector replacement is messing with AC power and interconnect wiring, while standing on a ladder near the ceiling while looking up through lower bifocals. It might be a job better left to an electrician, particularly since it is an important safety system. If I have smoke detector problems again, I will replace them.

 

[GlocksRock]

Glad to hear your situation has been resolved.

 

[Halon451]

Thanks for the update. Great to hear that the fam didn't force you to evict your new sub!