Scientific reports suggest 15cm is adequate and safe distance. The real risk is from MRI scanning for which technically there is no safe field.
That being said, I have LPs of female artists that make my heart skip a beat, especially if staring at large album art while listening. |
If yo utake out the woofer and place it hard agaist your chest: YES Very bad to do.
Otherwise no. The magnetic field from a woofer is very strong, but it is also very focused into the gap of the speaker. Most speaker magnets do not have much interaction beyond a few inches from the metal parts at all.
Noww really cheap speaker would be worse, and high quality ones better?/less errant field.
PS a speakers magnetic field does not get bigger the loouder you play it.
But some fringe types of field coil speakers DO. Thier magnet is powered, not a permanent magnet at all.. But those field coil speakers are rare, and need a LOT of extra power and stuff to make them work. they are also very expensive. And did I say rare.
So unless you are fondling the speakers all the time, I would say no issue is possible.
If you really worry, then have someone else install the speaker wires, and stay a few feet from the speakers.
This is not neccessary IMO, but to be super safe.
One way you could have a safety tool, would be to take a common boyscout compass. and magnetize the case at one point very slightly. So ony if the outer radiant field was stronger, would the needle move away from the tiny magnetized point on its edge.
It would only take the tiniest magnetic bit at the edge of the compass dial to lock the compass.. and if the needle moved, you would KNOW you are entering a stronger magnetic field.
I am suprised no one makes such a device. it would cost $5.
(But like audiophile stuff, a special MEDICAL one would cost $500 LOL) |
I agree with one half of what Albert just posted. I don't know squat about magnetic fields and pacemakers. But I agree that some of the album pics of my favorite lady artists make my heart skip, like Linda Ronstadt's pic on Living in the USA. Linda's wearing shorty-short roller skating shorts. What a babe in the day and a truly versatile artist to boot. |
Thank you! A bad heart ain't fun. Last year I had major surgery, took 3 months to recover, and aside from bond movies at any hour of the day, my own form of self therapy, recovery and meditation was listening to music.
I had asked manufacturers and others but never really got any definitive answers. |
PM member jadem6 or write to him through his cable company Jade Audio. He has a left ventricular assist device which I imagine is also v sensitive to magnetic fields. I know he has continued to remain active designing and building i/cs and speaker cables so I imagine he knows the ins and outs of this issue. |
Actually even a not treated compass could give you some idea of the magnetic field around your speakers. If the compass hardly moves when you are near your speakers, then you will know they are safe. |
I don't thik that anyone with pacemaker would go as extream as leaning against woofer. 2' away is safe.
consider placement of your rig at the safe distance from speakers or start playing music quiet and than adjust with volume control |
In the Emergency Department, we use magnets to temporarily turn off pacemakers to see what the patient's native heartbeat is doing. Only briefly, of course. The magnet has to be held directly over the pacemaker. So, keep the pacemaker at least a foot away from the large magnet. This advice does not apply to internal defibrillator-pacemakers. |
I have an implanted defibrillator/pacemaker, and do a lot of stupid things. I carried my Mirage 12" subwoofer upstairs and didn't think about that big magnet in the cabinet pressed against my chest. But no worries. It didn't turn it off. :-)
Mot |
Sorry if my Q is off topic, but it's kind of related. I have a 48" Panasonic plasma TV which has extremely strong magnets in it -- I think near the bottom of the screen for sure. Could be elsewhere too.
The TV sit on top of an entertainment cabinet which also houses my CDP and linestage -- all being tube pieces. The CDP sits on a shelf about 12" to 15" below the TV. The linestage is on a lower shelf about 24" below 20" below the TV.
Until I read this thread, it never occurred to me that magnetic fields could affect electrical devices like pacemakers, but it makes perfect sense. So ... how about my CDP and linestage. Too close for comfort??
Thanks and sorry for the hijack. |
Tgrisham, what's your advise for AICD's
That's the one really of particular interest to me-
Me and Medtronic, like Peanut Butter and Jelly- |
Zavato- My experience with AICDs is that each manufacturer has a different design. In some, the magnet will turn off the defibrillator part, in some the pacer part, some will reset the programmed settings, in some nothing at all. It generally takes a powerful magnet very close to the device. Anything greater than 18 inches would require a very strong magnet, more than what you would normally be exposed to. The best device is to call the manufacturer and also talk to your Cardiologist/Electrophysiologist to ask. They may or may not know since it is an uncommon question but it all will depend on the specific device, model and maybe even serial number of the device. Most have an alarm that is audible through the skin that alerts if the defibrillator is de-activated. Best to stay at least 18 inches or further away. It will not trigger a shock but may turn off the defibrillator until the device is reset by a technician/programmer. |
I've spoken to the electro physiologist and the Medtronic rep. Neither really didn't know but offered the same general advise- keep a reasonable distance. The alarm also activates when the battery is nearing end of life. I heard it last year.
Funny thing- I'm a litigation attorney and not long ago I deposed a fellow who claimed that his need for an AICD was because of an accident (BS) and then he listed a laundry list of things he claimed he could not do because he had an AICD most of which are nonesense (he can't operate a tv remote, he can't drive an SUV are 2 of his claims). After giving perhaps a half hour of perjurious testimony, I took out my Medtronic ID card and asked if he had one like it. Well, once he and his counsel realized they were piling on a load of crap to someone with first hand knowledge, the cardiac claims vanished. His AICD was real, just not accident related. |
Ha! Good story. I think to be absolutely sure you will have to contact the company directly. They should absolutely know what a magnet (any magnet) does to your device. It is in their literature. They just have to go look for it. I can safely assume the FDA makes them test it with magnets. And, yes, the internal alarm sounds when the battery goes below a minimum needed to deliver a series of pre-programmed shocks. Most also alarm when the device is not able to deliver a shock for any reason, even being de-programmed. |
