Slashdot Mirror
MagLev Trains Annoyingly Loud
crem_d_genes writes "You might hear that whistle blowing from that train coming 'round the bend, but tapes of the sounds produced by magnetically levitated and normal trains produced a result that was something of a surprise: Most people rated maglev trains as more disturbing than standard intercity trains. It had been previously known that the two types were about equally loud, but this study analyzed people's reactions to them. Since the effects on the environment will be part of the feasibilty studies for future development, acoustical engineers will have some new challenges. Some participants in the study said the sound made them 'feel insecure, some found it startling, and disliked the occasional shrill sound the maglevs produced.' The researcher postulated that unfamiliarity with the noise might be part of the problem."
Does anyone know of links to audio samples of a maglev? I've never heard one and some rudimentary googling didn't turn them up.
The quality of the noise source is as important as its intensity (i.e. decibels). Some noise patterns are just plain annoying. For instance, in noise studies, helicopters are considered more annoying and have lower acceptable decibel thresholds; the old Hueys are a prime example.
Can anyone explain this to me about um... "traditional" train sound, because I've always wondered: Why are they so loud at night? I know trains run through the city here regularly, and I can't hear the train whistles where I live during the day, even though I know they still toot them, but at night I can here the trains that have got to be at least ten miles from here. Why is that?
I would be curious if the sound of these kinds of trains carried in the same way. Normal train whistles aren't really unpleasant, but I wouldn't want to be listening to screeching noises from several miles away while I was trying to sleep. (The fact that I usually sleep during the day is irrelevant. =P)
My Webcomic: Asylum on 5th Street
Videos of maglev trains, with sound. My apologies in advance to the host.
/.'ing commence!
Let the
Sapere Aude - Homer
Of course, if it works too well it'll sound like someone's letting the air out of every tire in the block...
The sound of a regular train (been a while since I've heard one) is rythmic, higher pitch clicking. I would guess that the maglev might be more lower frequency. Also, one might wonder if there's a sound beyond the range of human awareness that might be contributing to the feeling that the maglevs are "louder" or more annoying.
I dunno ... you tend to feel louder high pitched sounds in your ears, whereas the lower ones you might feel more in your body.
The author of this post would like to point out that unlike other posts, this one was more stream of thought, and less composed than his previous ones. In other words, he's talking out of his ass.
I talk about stuff.
"Conventional" trains make noises ranging from low rumbles (slower trains) to what resembles gigantic versions of the "fwooooooooosh" of a racecar passing you (Acela and other modern high-speed trains). But loud, high-pitched sounds coming from a piece of machinery (e.g. a train) could make people think the machine is out of control.
;) ) and crush the hapless onlooker...
High-pitched mechanical sounds carry a connotation of machinery operating "out of control", or running faster than it should. I'll put it this way. If you walked into, say, a widget factory, and heard the machines cranking away with a low rumble, wouldn't you feel more comfortable than if they were generating a constant high-pitched whining? In which scenario would you fear, deep down in your gut, that one of those machines is about to go haywire, break down, and shoot a cog in your general direction? This is regardless of the actual speed of the machinery. Low sounds are just less unnerving in this case. (Or so I feel...)
Perhaps the sound of a maglev operating at 150mph would be more unnerving than that of an Acela train operating at 150mph since the nature of the maglev sounds would make it "sound like" it's more likely than the Acela to disrail (even though, as a maglev, it already is 'disrailed' in a sense
Honey, I shrunk the Cygwin
Under capitalism man exploits man. Under communism it's the other way around.
We don't get the freigh train whistle in The Netherlands, that I'm aware of. So the first time a freight train passed by me here in the U.S., you bet it freaked me out.
Now... I'm used to it.
Remember how when trains were first introduced, cattle would freak out, and the farmers were pissed at the railroad companies ?
Nowadays, trains zip by cattle many times a day, and they don't even bother to look up anymore.
Yes - people would just have to get used to the sound.
Unfortunately, people are still afraid of change - even if it's just a change in the sound of a train.
Where once upon a time new technologies were just introduced, we now run the risk of getting them bludgeoned to death by special-interest groups and environmental impact statements. There is no reason why in time maglev sounds should not become a familiar part of the soundscape, barely noticed if at all, and a realisation that people might be uncomfortable with something just because it is new may help us determine whether something really is damaging or if it's just a baseless case of NIMBY (as opposed to "it really is damaging, so get it the fuck away from me") when people oppose something new.
(aplogies if this is incoherent... it's been three hours since my last coffee)
That is something you'll always have with new technology.
At first the 'look and feel' of windows scared the hell out of me. While now it still does. Oh, wrong example.
Other ecample. At first ringtones used to annoy but now it just irritates me. Oh, wrong example again.
Privacy is terrorism.
I vote that they attach large speakers all over the maglev trains, and play the tie fighter sound while they are going really fast. That'll teach 'em to complain about the noise!!
I wonder if it's perhaps as simple as our built-in responses to shrill sounds.
Primates tend to make more shrill prolonged sounds when in distress. We are likely hard wired to go on alert when we hear distressed sounds from another primate. That would explain uneasy feelings and rating the sound as more intrusive and objectionable than a rumble and clicking sound which would be fairly meaningless to the lower parts of the brain.
It's a two fold problem that will likely call for psychologists and neurologists to determine what is so distressing and annoying about the sound, and then accoustic engineers to figure out how to alter the sound so that it no longer has that characteristic.
Nothing more than a hypothesis here, but quite testable.
The annoying sound is the one those people with pacemakers make as the train gets going.
the major advances in civilization are processes which all but wreck the societies in which they occur - A.N. White
The article was very skimpy on the details. Where were these tests done. How many people were tested. What kind of noise was it? There is noise pollution everywhere now-a-days. So, even if this comes as a surprise, trains are a great means of transportation, and seeing that the maglev is fast, there have to be more tests done before anything is concluded.
Guy That Sits One Cube Over ... Annoyingly Loud
... but subscribers can read it now by stopping by my office.
My Slashdot submission about this will be enroute to the Slashdot rejected bin in a few minutes
The web in some high speed paper mills moves at 8000 fpm, or about 90 mph. It's a 400 inch wide piece of nylon webbing, on top of which a warm slurry of .5% paper is sprayed at high pressure. It goes over rollers and dewatering points, where the water is sucked out of it by vacuum. Some of the rollers are small, so they have higher RPMs. At the other end of the machine, there are huge heated drums spinning at a faster rate (to pull the paper out). All of this is accompanied by pump noise, air compression noise, and vibration. It is so loud that earplugs are mandatory, and your chest hurts from merely being in the plant.
But I know exactly what its doing, so its not "out of control".
I want to delete my account but Slashdot doesn't allow it.
If they polled people living in a city with a lot of commuter trains, then these people might rate the mag-lev more annoying than the conventional trains that they are already accustomed to.
If they polled people living in an area without any trains and the people weren't used to conventional train sounds, perhaps they would rate the sounds of mag-lev's and conventional trains equally annoying or more close to equally annoying than the previous group.
Characterizing the difference between these two group may help identify how much of the results of this poll are due to people not liking the idea or sound of any trains near them and how much of the dislike is specifically due to the sound of mag-lev trains.
Additionally, I think that the results would be significantly different for those that may live in cities that would benefit from mag-lev's and those that live in small towns that high speed mag-levs may pass through without stopping (One may have a more negative opinion about the sound of a mag-lev if the sound does not have any associated benefit for the individual)
Perhaps the most impartial group to sample would be a group in a city with no trains and no plans to get a mag-lev in the future . . . but then who really cares about these people anyway (with respect to the sound of a mag-lev that they will never have to deal with on a regular basis)?
Unfortunately this article, like so many others, draws conclusions from the data without giving the reader enough information to draw his or her own conclusions or even agree or disagree with the author.
.. but tapes of the sounds produced by magnetically levitated and normal trains
Maybe they shouldn't have used magnetic tape around gigantic magnets.
I have to say, I live in the city right next to an Acela track, and it's one of the most amazing things I've seen. The tracks in question have MBTA (commuter rail) trains, Acela express trains, and T (above-ground) subway cars pass by on a regular basis.
The loudest and most annoying are the dilapidated orange line subway cars, which are very old and make a lot of clicks and clacks and screeches. The commuter rail is definitely louder, but it is uch more pleasant - a bassy rumbling, depending ont he speed, maybe more ominous if you don't know what it is. The Acela is QUIET in comparison - it seems as if the only thing you can hear (not true, of course, but comparatively) is the air being so violently pushed around as it whooshes by. And it's so quick (when not even at full speed in the city) that it's almost tantalizing, making you wish you could see it for a little longer. It's almost like an arrow shot from a bow, it sneaks up on you as you can't hear the rumbling as it approaches, and then it's gone by so fast you're almost not sure if you really heard it in the first place.
Three years ago, I went went on a guided tour to Papenburg/Germany and had the chance to experience the Maglev for about 20 minutes. First of all: don't believe what critics say. Try it yourself - if you get the chance to ;)
The Maglev is definitely NOT loud, nor does the sound make you feel uneasy (you could barely hear a train passing at 100mph, and a full-speed maglev was not at all annoying either!). Plus, there are no vibrations - a little different from conventional high-speed trains.
The top speed was 430kph (almost 270mph, on tracks initially developed for a maximum speed of 100mph - the tour guide claimed).
just my 2 cents
High pitch sounds are more painful to listen to, but they are easier to block than low pitch sounds which can travel thorugh the ground, especially at ground level where barriers can block noises. High pitch sound doesn't travel as far either. I would wager that being right next to the tracks would indeed be a painful experience, but half a block away I bet it isn't as bad and 2 blocks away is probably easily tolerable. I would bet that it has much less vibration which is a big problem for trains. Some steps they can take to mitigate noise:
1. Planting heavy shrubs near rail lines. Plantings can be designed to absorb specific sound spectrums.
2. Sound blocking berms or fences.
3. Double foundation walls with an air cavity between which don't allow sound transfer through the ground.
4. Larger setbacks from the noise source.
(Pulse Width Modulation, PWM) of the power to the electromagnets. That frequency can be changed, within limits. I've been on mag-levs at Kings Island (Ohio) years ago, they are a bit annoying.
Insanity: doing the same thing over and over again and expecting different results. Albert Einstein
Noise of any type is a result of some inefficiency somewhere. Be it the air displacement from poorly developed skins and attachments or transforming the electricity with inexpensive components. I'm sure they can isolate the offending noise and design it out of the equation. Still did not get a good answer on here as to what exactly was causing the noise. Although there is some good speculation.
Once I'd seen what they were capable of (you'll have to imagine a hundred 20mm rounds per second hitting a soldier; I'm intentionally not seeking a link), that sound took on a whole new meaning.
There's a whole ethical debate on this sort of imagery: can national security be weakened by US citizens being repulsed by the carnage our weaponry is capable of? Imagery impacted US public perceptions of the war in Viet Nam, and we've advanced a lot technologically since then.
I realize I'm off topic by here, but whining about maglev (pun intended) seems silly in comparison. As with jets and computer fans and traffic noise, maglev's purpose is considerably more benign. We can work around or get used to the sound.
The frequency content of a sound has a lot to do with how comforting or annoying a sound is. Incredible ammounts of money have been spent on this in the auto industry alone. Studies are done on the sounds of a car door closing to find the sound that makes people feel the most secure when the door has closed. What they've found is that the sounds of car doors closing with more energy in the low end of the frequency spectrum makes people feel more secure in the sound of a door closing.
Now lets apply this to trains. Normal freight trains generally produce a lot of low frequency sounds. Generally around 300Hz and below. Now the maglev trains could be a lot quieter, but if they make higher frequency sounds, even at lower dB levels, the sound will seem a lot more annoying than freight trains.