stereo systems with large speakers

Speakers safe

by LondonAndy - 2020-06-12 03:19:45

I have sat on 3ft (1m) high speakers in a nightclub, feeling the vibration of the bass, without any issue.  Just don't stand with one close to you - the normal advice is a 6" gap, but not sure if a 12" gap might be wise when they are on - "large" is a bit vague!

stereo systems with large speakers

by Maddy - 2020-06-12 05:59:23

The speakers are about 2`6" high and the system has a thumping bass.

Speakers

by AgentX86 - 2020-06-12 07:37:18

The issue with speakers is the large magnet in the speaker itself. Large speakers (not the cabinet) generally have a large magnet. However, the large cabinet keeps the actual magnet further away from you. Perhaps a larger problem is the smaller but still very strong rare-earth magnet in higher end headphones and even cell phones. While the magnet is smaller it can be placed much closer to your PM. The magnetic field falls off  as the cube of the distance, so double the distance and the field drops by a factor of eight. Distance is the key.

speakers

by Maddy - 2020-06-12 22:59:27

Thank you for the detailed advice you gave me, so very helpful. Can I encroach on your knowledge by asking about car radio/cd speakers? 

speakers

by Maddy - 2020-06-12 22:59:31

Thank you for the detailed advice you gave me, so very helpful. Can I encroach on your knowledge by asking about car radio/cd speakers? 

More speakers

by AgentX86 - 2020-06-13 00:01:36

Car or CD speakers are the same deal.  Distance is everything.  The only warning I was given was that some high-end headphones, ear buds, and cell phone have fairly good rare-earth magnets in them.  If someone were listening to their tunes laying on your chest, you might have a problem so don't do that.  I don't think I'd want anyone laying on my PM anyway - not comfortable at all!

Note that will all this stuff, how you're affected has a lot to do with you specifically.  If you have a low pacing percentage none of this stuff really matters because your heart is doing almost everything on its own.  OTOH, if you're dependent, there is a lot more to worry about because, by definiton, you're relying on your PM doing the right thing to survive. The chances of something bad happening may not be any higher but the results are a lot different.

General advice re pacemakers and interference

by LondonAndy - 2020-06-13 16:00:27

I can tell that you are generally anxious about what might affect your pacemaker, Maddy, which is understandable when we have a new medical thing to worry about.  I am 100% dependent on mine, which is now almost 6 years old, so believe I would notice if anything affected it.  So far nothing has.  

I believe that current devices are so well shielded that concerns of the past are largely no longer there.  If they can continue to perform when we are inside an MRI machine, which is basically a huge magnet, then that is pretty safe.  Yes, they have a technician stand by when they do this, but I asked my guy when I had an MRI if anyone had ever had an issue and he said no.  I am sure there will be some exceptions to this broad statement, but if your pacemaker is affected by something it would be temporary, whilst you are in proximity of the source.  

I am perhaps a bit more cavalier than some, for example whilst I always carry my pacemaker ID I don't tell the airport security people about it and go through the metal detecting arches along with everyone else, but I hope your device won't cause you anxiety and instead will help you with a normal life.

There are still some things I wouldn't do though!  Like go into a scrap metal yard where they have those big magnets that pick up cars, or industrial recycling centres where powerful magnets are also used to separate metal from other products.  Or electricity substations etc.  And it seems some roller coasters with magnetic brakes might be a no-no too, which is a shame.  As AgentX86 says, as long as you keep a little distance between your device and the type of things in our domestic lives we use all will be well.

I would be interested to hear if anyone can post where their device HAS been affected, and have a hat handy to eat if required ;)

no problem

by dwelch - 2020-06-13 21:29:43

loud music and speakers are fine.  have fun.

stereo systems with large speakers

by Maddy - 2020-06-13 22:10:39

Thanks, everyone

MRIs

by AgentX86 - 2020-06-13 23:20:17

Even though MRIs are huge magnets, we can (usually) have them because there is a PM tech there who save your settings to his laptop thingy, puts your PM into a "safe mode" (where all feedback is shut off and it's pulsing at a constant rare), then after he reloads your settings back into your PM.  Any data "upsets" will be reloaded back to their original settings before the PM is taken out of "safe mode".  Outside an MRI, a strong magnetic field may upset the settings but there is no one there to reload your data.  PMs cannot be shielded from magnetic fields.

The larger problem is AC magnetic fields inducnig a current in the leads, confusing the pacemaker.  The induced current may tell the PM that your heart beat on its own (over-sensing), when it didn't (so it inhibits).  This wouldn't be good, particularly if you're dependent.  Fortunately this is fairly rare but it is something for those of us who are dependent to be cognizant of.  My EP banned me from riding a lawn tractor (alternator sitting right under the seat), for instance.  I now have someone do the lawn.

Magnetic field interferance.

by TAC - 2020-07-25 13:46:36

In April (three months ago), I wrote in this forum about a possible electromagnetic interferance with my PM. I was programing a SONOS  speaker with a WiFi router and I felt something in my heart that made me panic. I thought the WiFi or the magnet of the speaker had triggered something in my PM. In a recent visit to my electrophysiologist, he interrogated the PM and no incidents or events were recorded on that date and time. I believe now, that since I was very self conscious of a possible interferance, I over reacted to something minor and unrelated to my heart. So, there was no interference from WlFl or from the SONOS speaker. Ever since, I downloaded a software in my I phone that checks for electromagnetic fields and I have been surprised that electromagnetic fields in most devices stay prety close to that device. So if you keep your distance, almost anything in the house is safe.