Do ear buds cause hearing loss?

make our classic joke. Right. Well, let's let's clue in our our listeners to what we're talking about, and we'll do that through a little listener mail. This listener mail comes from Christopher, and Christopher says, hey, guys, I was mowing the lawn the other day when I thought I would break the monotony and listen to my iPod. Then I thought how I would need to crank up the volume super high in order to hear anything over the

sound of lawnmower. I decided that this probably wasn't the best idea and went on mowing the lawn in complete boredom. That got me wondering how do earbuds affect a person's hearing? I know it can't be healthy to listen through earbuds at a volume level where someone across the room can tell which A C D C song you're listening to, But I'm sure earbuds will still have a negative impact at lower levels. How do I know what a safe listening level is? What, if anything, our company is doing

about this? Thanks a much, Christopher Chris So obviously my joke at the beginning was a joke in poor taste about hearing loss which I actually have. What Yeah, nice, I was putting it in context there, so and and polite of course is a percussionist. Now, just a quick question, do you do you actually have hearing loss? Not that I'm aware of, But then again I've been I've been practicing and actually performing with ear plugs in for years now,

very very wise. And as a matter of fact, to to Christopher's point, I mow the lawn of ear plugs because I don't even the sound of the lawnmower by itself without adding music or something else on top of it. You know, that's that's pretty loud. So that is Mr Pillette's version of the rock and roll lifestyle. Yeah, if it's more like the soft rock lifestyle. Nice nice, Well, Jonathan Colton has a song for you. Um, So I was going to talk a little bit before we really

get into the whole earbuds thing. Yeah, I'm gonna talk a little bit about how hearing works. Oh, that's a good idea, so that we can kind of get a handle on why loud sound can be a problem. So here's the general process that happens when we hear a sound. So, of course sound travels and waves right there, sounded as created as a longitudinal wave and as it crashes into the medium, they create a uh different kind of wave, right, you know, longitudinal waves right right, So you've got these

these waves. Essentially you have air molecules banging into each other, right, and then those travel they get captured by your ear. Your ear is shaped in the way that is, it's kind of like a funnel sort of funnels sound into the canal of your ear um. The sound travels down and it it makes contact with your your ear drum right right, So this causes the ear jump to vibrate. Now, the ear drum is connected to a little bone that we call the hammer um. It's one of three tiny

bones that are in your middle ear. There's the hammer, the anvil, and the stirrup, all right, right, So the hammer is connected to the anvile anivivals connect to the stirrup, and the stirrup is connected to the cochlea, which is the snail shaped element in your inner ear, all right. So the ear drum vibrates. This in turn causes those bones to vibrate and it kind of presses against the

little Think of it like a little window in the cochlea. Now, the cochlea is filled with fluid and actually has two chambers separated by a membrane, and the membrane has a tiny little hole in it which allows the fluid to move back and forth between the two chambers. And inside the cochlea are thousands and thousands of little cells with tiny little hairs in them. Now, as the fluid vibrate or moves through the cochlea, that causes those hairs to vibrate.

These these vibrations get converted into electrical impulses which go to your brain, and that's how you perceive sound. Your brain receives that that those electrical impulses and says, ah, that's a dog barking. All right. So that's that's it's kind of a it's actually a really fascinating process. I mean, anything that involves that kind of level of biology to

me is fascinating. Um. And if you remember when we did our Cyborgs podcast, we talked about cochlear implants and cochlear implants bypassed the ear drum, bypass all of that. They they have electrodes that actually go against the cochlea so that it it simulates those electrical impulses that would otherwise have been created by those little tiny hairs. Here's the thing. Those cells inside the cochlea are both delicate

and they do not heal if you damage them. If you damage those cells, if they they they stop working, you start to lose hearing and there's no way to get it back. Right now. That's a bummer. Yeah, So I mean to put it mildly, I was trying to be sort of something facetious, but yeah, I mean, that's that's serious. It's something that you don't want to mess with, right And I mean there's like twenty four thousand of these cells in your in each cochlea, and like I said,

you know they are easily damaged. And once they're damaged, that's it. And loud noises can do that. It's you know, you think about it. The vibrations of your urge from are fairly small, but they're magnified by those three little bones because they're they're pressing against a very very tiny spot on the cochlea. So everything that happens to the ear drum is magnified once you get down to the

cochlea level. So if you're playing really or listening to really loud sounds, or you're subjected to really loud sounds, um, you're really given it a workout. So that's what can actually cause damage to those cells. And we're not talking about just using earbuds. This can be any kind of loud sound, right, that could damage You're here, you don't even have to have headphones on, I mean if you were.

That's why you see people who work at airports having ear protection on at all times, because if you know those jets make up, they make really loud noises. And of course we we measure these noises and decibels and uh and in general, once you get over a hundred decibels, you're starting to get into the dangerous area. And it's it's a matter of not just the intensity, but the

time that you spend listening to that sound. Right, So, if you hear like a really loud noise, it's not like you're going to necessarily suffer damage just from one I slated incident. But if you're hearing a series of loud noises, for example, an A C D C concert for a nice long time, that's more likely to over the course of the evening cause hearing loss. And it may not be perceptible immediately thereafter. It just might mean that you will experience more dramatic hearing loss faster than

you would otherwise. Yes, so let's get down to earbuds now that we've covered those bases well at the answer to the question that that Christopher post this is actually fairly simple, depending on whom you ask um for me, I would have I would have asked Dean Garstecki, Northwestern University. Guy. Yes, the professor in the chair in the rox Lyn and Richard Pepper Department of Communication Sciences and Disorders. Audiologist is

what is one of his titles, that's the shorter one. Yes, anyway, he deals with here and hearing loss and knows a lot of people who do. Um and uh, which will be important later. Um. And the thing is, he says, um frankly, he has what he calls a sixty sixty rule. Have you I think you've seen this. I got mine

my information from a Science Daily article. Um. But yeah, apparently he believes that you should listen to music on a set of earbuds no more than sixty minutes a day in twenty four hour periods, at no more than so, uh, that's pretty simple. Don't listen to your earbuds for more than an hour a day at just a little bit more than medium volume, right and uh. And he bases this mainly as far as I can tell off of a typical iPod player. And now the article that you

are referring to, I read the same one exactly. I think it was written in around two thousand five. Yes, it was the iPod that was built in two thousand five that they were talking about. Had a maximum volume level of around a hundred thirty decibels, which is above the threshold for what could cause hearing loss if you listen to it for for any extended amount of time. So six of that would be presumably safer as long as you listen to it for an hour or less. Um.

Here's here's another thing about earbuds. It's interesting. Earbuds can actually boost up the the decibel level. Um, Like, if you were to measure the decible level by just say, hooking up a regular pair of headphones and measuring it that way, a pair of headphones that would actually go over over your ears over the ear headphones or even just the padded kind not necessarily over the ear, but

you know they don't go into the ears. Yes, on your airphones headphones rather, um, those might come in at let's say that you measure it and it comes in about say eighty decibels, all right, earbuds can boost that up up to uh up to nine decibels more than the equivalent headphones. And part of that is because it's closer to your your actual ear drum, so the sound waves are traveling a shorter distance and they aren't dispersing

as much. They're there the intensity is higher. So the eighty decible sound you would get out of a normal pair of headphones is gonna jump up to eighty nine decibles in earbuds. Now, if you're listening at one of the higher levels, then you're you know, each you have to remember that as you get closer to that threshold, each time, each increment you go over the threshold is it's not it's not a linear um uh progression of how much more dangerous it is to your hearing. It's

it's greater than linear. It's not quite you know, lagarithmic, but it's somewhere in between. You just wanted to say logarithmic. I bet often at any rate. So, yeah, so he's got the sixty sixty rule. But you also have to remember, if you're using earbuds, you need to make that um take that into effect. And of course today you can find MP three players that have kind of self imposed limits on how loud they can get. Yes, some of

which you can work around. Right. Well, now, I was going to get to to that in and but the friends thing. The reason I brought that up was in that article he cited a friend of his who worked at Wichita State University. And apparently, what this friend will do, another professor will walk across campus and and as this friend is doing so, um, we'll find students wearing earbuds and we'll ask, we'll stop them and ask them take out the earbuds and we'll check to see how loud

they were playing. And in a lot of cases, the students were listening to music at a hundred ten or a hundred twenty deils. Yeah and uh and Osha recommends that you don't listen to any uh, any sound level greater than a hundred and ten decibels for more than half half an hour a day. Right, So if you're listening to music at a D twenty and chances are you're listening to it for more than half an hour. Most of us, I think probably listen to you know,

I'd say half hour is a good minimum amount of time. Well, that's the thing is, according again to this article, UM, all volume at that level can cause hearing loss after only an hour and fifteen minutes, which is a pretty

short period of time. When you think about it, that that probably factors into the UM and UM you know, basically, uh, the thing is you you there are factors that you can and take into account, like the distance between your ear and the source of the sound and the volume of course, but one thing that the iPods and other music players have today that say the early the Walkman and UH sound players of the nine eighties and nine ninies don't have is a much longer battery life, and

that's a problem because, um, they will last for hours and hours, especially when they're new, and if you're listening to music UH within ear bud in your ear at that volume for an extended period of time, you're more or less guaranteed to cause hearing loss. If nothing else, you have the ear fatigue, which you know, that's when you when you take them out and you just feel like like things just don't sound right to you anymore. Everything's kind of muffled. That's a good indication that you've

caused some some damage to your hearing. It may not be it may not stay that severe for forever. It may be that gradually you start to, you know, notice that you've got your hearing back. But what it means is that those cells, even if they aren't dead, are damaged, and that over time they can get more damaged until they stop working entirely. So it may not mean that you lose a perceptible amount of hearing at that time, but it means that over the long run, you're gonna

lose your hearing. Faster than you would have otherwise. Um. And it has been going on since the the ear the headphone phenomenon of portable music players, having your your music with you anywhere and everywhere. Um. You know, the research I I had seen basically said, you know, yes, there there have been more people losing their hearing before you know, old age, when you might expect people to

start losing their hearing. Um, since people have been carrying around their music with them and using portable music players. So yeah, it's it's certainly an issue. The Center for Disease Control and Prevention out here in Atlanta actually reported that noise induced hearing loss. Uh, they found noise induced hearing loss in nearly thirteen percent of Americans between six and nineteen. So you think about that. I mean, yeah, hearing loss is usually one of those things that comes,

like you said, along with aging. But between the ages of six and nineteen, you know, these are these are when you're still growing. Yeah. Um, well maybe not nineteen, I mean, but I was growing at nineteen. I was just growing out. Uh. Also, I thought i'd ask you

you're familiar with the term tenitus. Oh yeah, Oh, I was thinking of it from that Beatles song you know, the girl with Tenitus goes by anyway, So, um, so about forty to fifty million Americans experienced some degree of that, and uh, hyperacusis or I'm just gonna say hyperacusus because I have no idea if that's the correct pronunciation, and I don't even want to try a different one. Um. But yes, the tenetus or tenitus is that it's kind of it's it's a it's a persistent sound that you

hear that's not generated by any external um source. So usually it's like it's normally described as kind of a high ringing noise, but it can also be a buzzing or a worrying noise UM. And then there's uh, it's it's one of those things where it can it can actually interfere with your hearing of normal sounds, even though there's no perceptible like someone who's staying next to you is not going to hear it because it's all in

your in your here ing. Yeah. As a matter of fact, a number of rock stars have come forward um to talk to young people about listening to music to live because they've said, you know what, listening to the loud music like I have been every day, you know, with these large amps behind me. Uh, well, damage your hearing because it's damaged mine. And you know I'm thinking specifically, you know, people like Pete Townsend. Um you know who. I think he actually suffered a burst ear drum due

to a certain Keith Moon and his exploding uh drum kit. Well, yes, however, I don't think a small explosives count in the earbud department. But yes, those are also bad for your ears. So so here's a hint, be careful with earbuds and don't play directly in front of Keith Moon. That second one actually be pretty easy. One's pretty easy these days. Um, thanks a lot, it's that Um okay, So I was going to make Keith Moon jokes to a drummer, Yeah, no kidding. Uh yeah, he's one of my favorites too.

Um Joseph birds Song and Bruce Wagoner. Did you run across these names? They are? There are two people who filed suit against Apple, uh specifically against Apple, saying that it's ear drugs. The earbuds were designed to be put deep into your ear canal and uh is you know, are specifically going to be a problem. Um, you know They also argue that there is no visual representation of the volume. Of course there is when you're actually speaking

of somebody who's owned two different generations of iPods. Yes, you can see roughly how loud it is as you're you know, making a change to the volume or stopping or pressing play. But you know, if you're not looking at it, and you know, the screen goes blank. No, there's no longer a visual representation of volume, nor is there sound isolation. And they were asking for for monetary damages, not because they had actually lost hearing themselves, but basically, uh,

you know, to get Apple to improve safety, raise awareness. Um, it was better headphones. Right, It was more of a a a way to try and convince Apple to change there there processes and their systems so that people would

not suffer hearing damage down the road. Right, right, Well, the uh, the Ninth Circuit Court of Appeals, who has come up many times in our podcast in California, UM had affirmed a two thousand district court ruling about this membread an article and Reuter's about this that basically the planiffs didn't show that the use of the iPod poses

an unreasonable risk of noise induced hearing loss. Um and uh basically said that they didn't really have because they hadn't lost hearing themselves as a result of using the iPod, they didn't really have the legal footing to to bring a case against Apple. But you know, if they have raised awareness, um, you know, they I imagine they would say that they have achieved some measure of success. Although you know, certainly Apple is not the only one to

be packaging earbuds with its products. No, No, there are plenty of independent earbuds out there that work with just about any kind of device that has you know, essentially a three and a half millimeter headphone jack Um and Uh, I was gonna mention that, you know, it's really it's not difficult to create a product that that would uh minimize the risk of hearing loss. You just create one

that has a maximum output beneath the danger zone. Really, Um, what should be bad because he wouldn't be able to play that? Okay, you beat me to it, um, But at any rate, Uh, I'm amazed. You know, we've had what like three different three or four different music references, oh four because of a c D c um at any rate, the h it wouldn't be difficult to do that.

But I think that the the outcry, weak as it may be, from the hearing impaired, um, the outcry from the they outcry, the outcry from from people who the customers who are purchasing this and saying, you know, no matter how loud I turn it up, it's not loud enough. Um. I mean I know that. On my iPod. I actually bypassed the the safety because there is a safety on on Well. The reason I did was not because I want to listen to music at a you know, an

ear drum blasting level. The problem is that sound files aren't all recorded at the same volume level. So you listen to two different sound files and you you haven't even touched the volume, and one might be whisper quiet

and the other one might be blistering lee loud. Yes, the way that people have recorded sound over the past, uh you know, a few decades has changed dramatically, especially in the last years, and even the way that it's converted into the MP three format can that can be affected that way too, depending on on your on how you're converting things. Oh you know what I wish I had done research on and it just occurred to me

just now. I hate I usually have one of these in every podcast, and and normally I keep it to myself because I feel uh sad that I didn't think of it. But uh, I had read somewhere that um that basically because they are trying to improve the hearing of certain frequencies in music on recordings they want you to hear, UM basically enhance their accenting the parts that

they want you to hear. Let's say that they're accenting the frequencies because they're you're using compression and other techniques to make this work, make things seem louder. Um. I had read somewhere that, uh that it may cause people to lose the ability to hear in other frequencies as a result of that, basically, that we won't be able to hear anything between twenty and twenty thou hurts. Now. I don't know if that's true. I wish I've looked that up before this podcast, So don't write in and

say you didn't say whether it was true. I don't know. I'm gonna want to go look it up, and I might report back because that would be interesting to to know, and and maybe something that they have to do a lot of study on before they can really tell for sure. But that's sort of like the vestigial toe thing. Like I do remember hearing about audio engineers who complained that we're losing a lot of the nuance of of music.

We're losing a lot of the the high highs and low lows and and the subtle stuff, and everything is just becoming equally loud, which is also why you can suffer your fatigue as you listen to music, because it's all being blasted at you at the same intensity. There's no variation. And then you have, for example, headphones that limit you to say twenty to twenty hurts, and then you know all the things that theoretically you can't hear, but you sort of feel more than here, Um, you don't.

We really don't get that sort of an experience like you would say, if you were at a live concert and listening to it in in person. So it's it's really kind of fascinating. We think about the science of sound and how all that works, and and how our electronics are changing that and either enhancing or harding that in some degree. Sure, And on a related note, that actually brings me to a second round of listener mail.

This listener mail comes from Daniel, and Daniel says, high, guys, So I'm looking at buying the brand redacted headphones and was wondering, how are they stereo if they're binaral? What does binaral actually mean? Anyway? I thought it meant a single channel with two earpieces. Come to think of it, how do headphones work in general, especially the noise canceling time? Thanks Daniel, Well, we figured since this was kind of on the same subject, I would I would tackle this

really quickly. Binaral is actually a method of recording, it's not. It's not a method of playback. Alright, So you're familiar with the stereo recording system where you're using at least two microphones, right, essentially two microphones space channels two channels a channel per microphone. I've got one microphone. Let's say let's say you have one setup near like a speaker where it's the lead guitarist, and then another one that's over by the drums or whatever, and then by recording both,

you know, the microphones are a good space apart. You can get two different channels of sound, mix them together. And then you get this, uh, this more complex sound than you would if you use just one microphone, right, all right. Binaral takes that an extra step. Binaral. What they do is they take an analog of a human head, and by that I mean like a human head, usually a dummy, UM, sometimes a porsche lub who no, no dummy. They get a dummies head instead of ears as microphones

on the directional microphones. UM. Sometimes they go to great links to try and uh and and and simulate human ears. The idea here being that you set this down in a recording area, you play whatever the sound is, and it picks up sound as if it were a person standing in that exact location. So when you listen to the recording, the two tracks are never mixed together into a single track. It's you're you're you're getting one track

in the left ear and one track in the right ear. Um, and ideally you would be hearing the sound as if you yourself had been standing at the recording session at that one time. It's kind of a neat idea that works really well for things like classical music. I've heard it for audio drama, where you are essentially inserted into the audio drama as a mute participant. So you hear people walking around you and leaning over and whispering things

in your ear and that kind of thing. And what they're doing is they are physically walking around this dummy head and physically whispering things into this microphone, and you're hearing it as if you were you were there, I mean, the two microphones are spaced apart as if they were human ears, so you get the sound at about the same speed as you would if you were actually there. Impressive.

So that's binaral. So really, any pair of headphones can do it, and and any pair of stereo headphones can can do this sort of thing, and you could even listen to it on regular speakers, but you would lose that stereo effect unless you had really a good surround separation. Yeah, separation is very important with that. And as for noise canceling, that's also kind of interesting. The way noise canceling works is through a method called destructive interference. Now you talked

about the longitudinal waves. Yes, sound is created. The information I actually got from our article on how noise canceling headphones work, right, So what noise canceling headphones do is they have a little microphone in them that detects the noise and the environment, at least the active ones. The active ones, so passive ones, all they do is cover up your ears, right, So it's it's essentially the same thing as the same method as sticking the fingers into

the ears. That's essentially what the last I can Active ones have a microphone in them that picks up the sound in the environment and then it generates a sound

with the same frequency. But um, but turned a d eighty degrees, all right, So they the troughs and valleys, peaks and trops, I'm saying the same thing, the troughs and valleys, the depths and the valleys and the troughs, you know, the peaks and the trops, thank you Pullett, Uh match up so that you get one kind of solid bar and essentially the two sounds cancel each other out right. Um. They basically sort of make a form of white noise, if you will. Right. And since they

are active headphones, they require power. So that's why they need to have batteries in them, uh, because otherwise it can't generate that signal. Right, And you know, I've listened to music on noise canceling headphones, and the nice thing about them is that you don't have to turn the volume up nearly as much to try and drown out

all the ambient noise. That's the other problem with earbuds, right, is that they aren't good at canceling ambient noise, so instead of canceling it, you're just trying to overpower it, and that that in turn ends up causing damage to your hearing. Yes, and and as Garstecki said, um, noise canceling headphones or any kind of headphone that you can use to you, uh, you know, prevent to get it farther away from your ear, the source of the sound

farther away from your ear. That's going to help. And I assume that that's part of it too, is that you're not trying to drown out the outside noise such as I want to know, say, a lawnmower, right, so I drowned it out with more noise. So well, thanks a lot, Christopher and Daniel that those were great questions. Had a really good conversation there about the hope you heard it. Uh. If any of you have any questions, you would like to send us our email address is

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