How Is But Why Made? What Is Sound?
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This is But Why, a podcast for curious kids from Vermont Public Radio. I'm Jane Lindholm. I host the show. In this podcast, we take questions from curious kids like you from all over the world, and we find people to help give you answers. But why?

This week, though, we didn't have to look very far to find the people to give you those answers because you've been asking about us. My question is, why did you make but why? We were a little surprised to get questions about how and why we make but why. But then again, why wouldn't you be curious about what you're hearing?

Here with me in the studio to help answer your questions is Melody Beaudet. You've heard her name mentioned a lot. You don't always get to hear her voice, but Melody and I work together to make this podcast. Hi, Melody. Hi, Jane. So in this episode, we're going to answer your questions about how podcasts are made, as well as some other questions you have about the physics of sound and radio. But first, we're going to do some navel gazing. Do you know that expression? No.

A navel is another word for a belly button. So navel gazing means you're spending a lot of time thinking or looking at yourself.

So here are the first couple of questions. I'm Alex. I'm five years old. I live in Seattle. And my question is, how was But Why Curious Kids made? Hi, my name is Vivian, and I'm seven years old. I live in Peterborough, England. And my question is, why did you make But Why?

Okay, Jane, so why did you start But Why? Well, I thought that there might be a need for more programming that was designed for kids, kind of like public radio. I've been working in public radio for more than 10 years, and I thought, why don't we have public radio for kids?

And then it made sense to ask kids what they wanted to hear about, because after all, if you're listening, you want to hear about something that interests you. So I thought, let's have kids ask questions themselves and then we can find answers. And then I thought, well, let's make it a podcast so anybody can listen whenever they're ready. So you can listen to it on your way to school in the morning. You can listen to it as you're getting ready for bed or any other time that you want.

Melody, what about you? What do you do as a producer and why do you like Making But Why? I like Making But Why because I love hearing the questions that we get from all the kids from all over the world. And some of them make me laugh when I'm listening to them. And some of them I just find really interesting. And I say, gee, I really want to know the answer to that. And then I am especially interested in the questions that it's like, OK, well, I've tried to Google it.

and there's no answer. So how do we find that? Yeah, or the adults in my life can't figure out an answer. Can you? Right, exactly. And I like that challenge. So what do you do for the podcast? As I said, we don't often get to hear your voice, but you're doing a ton of work. Yeah, so radio producers do a ton of different things, and it's different everywhere you go. A lot of producers start with research. So again, somebody sent us a question, we don't know the answer.

It's time to start digging. So you start thinking about, OK, is this question related to physics? Is it related to farming? Is it related to animals? And then you start looking for the experts in those areas and find people who you think might be good at engaging with kids. But wait, Melody's starting to answer another question you've sent us.

Hello, my name is Micah and I'm almost five years old and I live in Indianapolis and my question is how do you make your podcast? My name is Jack. I live in North Vancouver. I

I'm five years old, and my question is, how is podcasting made? So podcasts are basically an old idea made new, and the old idea is the idea of an audio program. In the past, audio programs were mostly done by radio. And we've had radio for how long, Melody? Radio's been around for 100 years, actually over 100 years.

And the idea with radio was that everybody could hear the same thing at the same time. So everybody could hear a concert or everybody could hear the news that was going out. You didn't have to wait until the morning newspaper or wait for somebody else to tell you. Everybody could hear this important stuff all at the same time.

But the problem with that is maybe the time that I want to hear the news isn't the time that Jane wants to hear the news. And that's where podcasting comes in. Because podcasting lets you hear what you want, when you want. And podcasting doesn't happen over the radio. It uses a different technology and it works through the internet.

But before we get too far into the Internet and how podcasts are transferred over the Internet and how podcasts are made, we first need to understand some of the basics of sound and how that works. Right, because you can't even get a podcast if you can't hear it. So how is it that we're hearing sound? So we brought one of our friends from here at Vermont Public Radio into the studio with us to tell us how sound works. Test 1-2.

Am I left only? No, you're on both. Okay, so I can't pan this. Tell us who you are, Chris. I'm Chris Albertine. I'm a sound engineer. What does a sound engineer actually do? A sound engineer records the voices that you're hearing right now and makes sure that they sound good. Let's see if you can help us answer some of the questions that we've gotten about sound. My name is Eli. I live in Boulder, Colorado. I'm eight years old.

And my question is, what is sound made of and how is it made? Hi, I'm Alec. I live in Philadelphia. I'm five and a half years old. And my question is, how does sound work? So what is sound and how is it made? I guess the simplest way to put it is when something vibrates,

It makes sound. So if you think of a guitar string or you think of a harp or a string like that, that's the easiest thing to imagine. And when you pluck one of those things, it vibrates the air, the air molecules to be specific. And they go out unseen through the air and hit your eardrums.

And your eardrums vibrate back and forth and your brain interprets what it sounds like.

So I guess there are two pieces to sound because there's a thing happening that vibrates the air, but then there also has to be a receptor, which is in this case our ears, to hear the thing that's vibrating the air, to actually hear a sound. But the thing is happening, that air vibration is happening whether you hear it or not. Right, but it really has to go through your ears to be interpreted, whatever it is. A way to think about it is if you look at a speaker –

and you watch it bounce in and out, that is literally pushing air out through the atmosphere.

And your eardrum is working the same way, only in reverse. So it is interpreting to your brain what is coming through a speaker. When you talk about a speaker pushing the air out, going back and forth, that kind of helps us get an idea of what that physical movement through the air is like. It's kind of a wave. It's a peak and trough and peak and trough. And we have a couple questions about sound waves. Right.

Hi, my name is Molly, and I'm 5 years old, and I want to know, I can't see my boys' ways, and sound waves are invisible. Hi, my name is Lydia, age 6. I live in Burlington, Vermont. My question is, why can't we see sound waves? Because they are literally pushing molecules.

So your eyes can't see air molecules to begin with, but they exist. And when they are pushed, they spread out. An easy way to think of it is like dropping a rock into a pond and you see a circle of waves emanate out and gets wider and wider until it hits a rock and it stops or bounces off and starts going the other way.

or it hits the grass and it gets absorbed.

And so it's like that with sound, but you can't see it because you can't see the air molecules. Right. You can see it happen in water, but you can't because water has a more solid feel to it. Now, sometimes there are things that you can see and you can hear, like thunder and lightning. Right. But you don't see and hear them at the same time because light and sound actually travel at different speeds. Right. Sound is much slower than light.

So if you're far away from someone and you clap, they'll see you clap before they hear the clap. Right. Another good example is when a really fast airplane goes over, you see the plane and then a second later you hear the sound. It's kind of neat. It is kind of neat. Is that kind of the principle behind an echo? Well, not exactly. But we do have some questions about echoes. I'm the echo.

I'm Major Golden from Petoskey, Michigan. My question is, how do echoes work? Wow, well done illustrating the sound of an echo in your recording, Brielle. Hi, my name is Mayel. I am seven years old, and I am from Missouri. And I would like to know how are echoes made? An echo is when you shout something, and it hits a solid wall and comes back to you.

So the sound hits a wall or something that won't absorb the sound. And depending on how far away that solid object is will depend how long it takes to hear that echo. So in a room, you don't hear the echo as distinctly. But if you're shouting across a canyon, however long that sound takes to reach the opposite side of the canyon and then however long it takes to bounce back into your ear,

is how long the echo is. So you could actually measure distance by using sound. Right, which is how sonar works. Or echolocation that bats and dolphins use, right? Yep. They bounce the sound off an object and...

they're able to tell just by how long it takes to come back into their ears. Chris, another question that we got is from Minnie. I live in Brookline, Massachusetts. I'm seven years old. And my question is, why do soft things absorb sound? Thank you. Why do soft things absorb sound? Again, it's if you think of like the echo.

When you shout into a hard surface, that gives the molecule something to bounce off. So if you're shouting into, say, a cushion or something like that, it's porous, meaning that there are small holes in it that allows the sound to go into, and there's less of a hard surface that will allow the sound to bounce off of.

You might think of it like if you're bouncing a ball on a hard surface, it's more likely to come back to you. But if you try to bounce a ball on a pillow, all of that energy gets absorbed by the pillow and the ball doesn't bounce back. It's the same way with sound. Right. Or if you have a bucket of wet cement and drop something into it, it'll sink. And if it's hardened cement, it'll bounce up. That sounds like a fun experiment. Yeah.

But here's the confusing part. You're a sound engineer. You work with sound. But when you're working with sound, you're both listening to the sound, but you're also seeing it through the computer program that you use. And in this business, we call it cutting tape or cutting sound. But if you can't see a sound wave...

How are you visualizing it on the computer? Because electronically, sound doesn't travel through the air. It travels through electrical energy. So when you plug a microphone in, it sends those sound waves through a wire that will then be interpreted by the computer and actually draw a picture of what's recording or what you're hearing in

And you can tell a lot just by looking at the picture of that sound wave. You can tell how loud it is. You can tell what pitch it is. So would your voice look different from my voice? Yes, because a lower voice or a higher voice, the more a sound vibrates. And you also have to think of this when you speak. What's vibrating when you speak are your vocal cords, and those vibrate, and that's what gives everybody their distinctive voice.

But when something vibrates fast, it has a higher pitch. And when something vibrates very slow, it has a lower pitch or the bass. It's got more bass to it. So when you think of a bass, it's like boom, boom, boom, boom, because it's vibrating very slow. But something very high pitched, if you think of like,

you know, the thin string on a guitar that vibrates faster than the big string. And so that's going to look different in a computer program that's interpreting the sound visually for you to make it easier for you to edit. Right, because the pitch of a sound is measured by how many vibrations per second it makes. So something that makes more vibrations per second is much tighter together on the screen. Right.

and something that makes a lower sound vibrate slower. And our ears are limited in what they can hear.

They can only hear something that vibrates at, say, 20 times per second. That's the lowest sound we can hear, up to about 20,000 times per second. And that's more like a dog whistle. Some people can hear it and some people can't. Yes, and we've done episodes before where we learned that elephants, for example, can hear really low sounds that humans can't hear. And dogs, as you mentioned, can sometimes hear much higher sounds than we can hear. Right.

So, Chris, before we let you go, what interests you about working with sound? Why do you like this job of being a sound engineer? You know, I kind of like sound because sound is interpreted inside your head. It brings the world inside you.

As opposed to seeing something, which allows you to look out and see something. But sound has to go into your ears and you have to interpret what that sound is. And it's different than looking at a picture that you can see the color, the shape or whatever. This is – it's hard to describe. But I've always liked the fact that I think sound makes you feel more than seeing something.

Are there any special skills that anybody listening today who wants to be a sound engineer should be practicing while they're still kids? Listening. The more you listen to the world, the more familiar you are with the different sounds around you. And that's important if you're doing sound for things like TV or if you're putting sound on picture, then you have to know what it should sound like. And the other thing is listen to music. Why?

because that's the sound that makes you happy or sad. Music is what, you know, carries emotion in it. And protect your ears. Oh, yeah, definitely got to protect your ears. I never go to a concert without earplugs. Chris, thank you very much for talking with us. Okay. Before we get too far away from sound, one of you had a question about microphones. My name is Ellen, and I'm from Avon, Indiana. And how do microphones work?

A microphone converts sound waves, acoustical energy, into electrical energy. That electrical signal travels through the microphone. If you're recording, that signal gets recorded or saved onto your audio device. And then when you want to play it back, your speakers basically take the same process but do it in reverse. So they change the electrical or digital signal into sound waves so you can hear it.

Coming up, we'll learn about how radio works and we'll give you the inside scoop on how our show is made. This is But Why, a podcast for curious kids from Vermont Public Radio. I'm Melody Beaudet.

Today, we're talking all about sound, and we're talking about two of our favorite mediums, podcasting and radio. Okay, so now we know the basics of how sound works, but how does sound get, say, to your radio? Maybe you listen to the radio in the car on the way to school sometimes.

So we know that that sound is traveling to your ear, but how is it even getting to your radio? Radio waves are really complicated to understand, and so we brought in somebody who has thought a lot about how radio waves work. My name is Joe Temecki, and I'm the head of technology at Vermont Public Radio. Joe's actually been working in radio since he was a kid himself. Well, the first radio station I was ever at...

was the St. Michael's College radio station. I was 15 years old, and I had an FCC license, and I worked as a disc jockey. Why at 15 did you want to be on the radio?

Because I had been listening to the radio since I was a little kid. I was a kid who had a transistor radio under the pillow, listening to radio all night long. You're going to have to explain to kids listening today what a transistor radio is. Yeah, so it would be like putting an iPhone under your pillow and listening to music all night. Except it wasn't an iPhone. It was a small radio about the size of two candy bars. And it ran on batteries, and you could listen to local radio stations on it.

So that's Joe's story. But that's not why we asked him into the studio. We needed him to explain radio signals. Here's a question from Ella. I'm from Burlington, Vermont, and I'm eight years old, and my question is, how do radio signals work? Wow. So the easiest explanation I can think is it works a lot like light waves or like light coming from a light bulb.

We have a thing on the mountain called an antenna, which is kind of our light bulb. And the energy that comes from it, unlike light, you can't see it. The energy that comes from a light bulb you can see. The energy that comes from an antenna you can't see. But they're very similar in that they both travel in a straight line.

So if you imagine there's a super bright light bulb on top of Matt Mansfield shining in all directions, that's what our radio waves are like. They're at a different frequency, so we can't see them with our eye, but they can be picked up by a radio. Well, here's what's confusing to me. We've been learning about sound, and sound is vibration that moves through the air to our eardrums, and we interpret that vibration as a sound. When I'm listening to a radio, I'm also hearing the sound.

But I can't hear a radio signal. I can't hear the particles moving through the air. I'm not hearing a radio wave. So how does a radio signal carry sound if I can't hear it? And then how do I hear it through my radio? So the radio's job is to convert the radio wave to sound. There's a thing in there called a speaker which moves back and forth. And maybe Chris explained that to you already. Yeah.

So that's air moving back and forth, and that's sound. The radio waves don't travel in air. They actually travel through—why am I wearing this? It's not air moving back and forth. It's magnetic fields that are moving back and forth. And they move back and forth in a way that represent the sound. They don't have sound in them, but they represent sound.

I think that makes sense to me. Because, I mean, one of the interesting things then is, you know, if you think about a sound, a sound can only travel so far for you still to be able to hear it because it'll either hit something else in the meantime or it dissipates over time. It dissipates pretty rapidly. Yeah.

But a radio signal can travel much farther distances, right? It sure can, yeah. So it's carrying that sound through these electromagnetic particles over a greater distance and maybe— Electromagnetic waves, actually. Electromagnetic waves. Yeah. So it might carry it from one radio tower to the next radio tower that could be 20 miles away? Or more. Yeah, we have—

Special types of radio transmitters and receivers that we use to get our signals, like from the studios here in Colchester, they get up to Mount Mansfield. That's 25 miles away. We can also relay those signals across the state. Basically, it's line of sight, just like light. So if I'm holding a flashlight and I walk around the corner, you're not going to see the light from the flashlight anymore.

If I'm on top of a mountain and I'm holding that flashlight and you go behind a hill, you're not going to see the light from that flashlight anymore. And the radio wave is exactly the same way. So if you are within line of sight of the radio tower, then you'll get a signal.

Now, my radio in my home is not in line of sight to a radio tower. So how are we getting that sound from the radio tower into my radio in my car or my radio at my house? So you may not be able to see it, but there is still some signal that sort of makes it. It kind of creeps over the horizon and around trees and through the walls of your home.

So it's not exactly like light, but that's the best analogy I can think of. So are there just electromagnetic waves around us at all times? All the time, from everywhere. What else produces these radio waves? The sun produces radio waves. We can listen to the sun. Your mobile phone produces radio waves. The baby monitor produces radio waves. The wireless internet camera that you use to check on your dog produces radio waves. It's literally everywhere.

So the radio's job is to sort out all of those radio signals and just pick out the one you want.

And that's how radio stations work. They buy a signal, right, so that then they can broadcast on that signal. And you know to tune in to 107.9 if you want to listen to VPR because that's where you're going to hear it. We actually lease it from the Federal Communications Commission. The frequencies, they're owned by the United States government, by the people of the U.S. government. And we get a license that lasts for eight years. So every eight years we have to renew this license.

You understand a little bit of the technical aspects now and how sound works, but what about how we actually make the podcast episodes that come to you? We're going to take you inside our process now. Don't tell anybody because we want you to understand what goes into actually making an episode all come together that you're hearing right now.

And to do this, we're going to talk about one of our episodes from a while back. You may have heard it. It's about why the sea is salty. This was an especially fun one because we got to get out of the studio and go to the sea itself. We went to the Gulf of Maine, and I met an expert there. So we're going to take you through a little bit of that episode so you get a sense of how sound works and some of the things we never include in an episode that you get to hear. My name is Zach Weitner, and I'm a research associate at the Gulf of Maine Research Associate.

That's not where it is. Boy, okay. My name is Zach Whitener, and I'm a research associate at the Gulf of Maine Research Institute in Portland, Maine. But wait, there's a lot more that goes into it than just going to the ocean and hoping there's somebody there who can explain why the sea is salty. First, we've got to decide, okay, we're going to talk about the ocean. Then we have to find the right person, and that's something that a producer does. And that takes time and research and phone calls and emails, and then you get to go to the beach. Hey!

So as you can hear, we're at the beach. We're recording a whole interview. I'm recording the sounds of the ocean and the sounds of the seagull and maybe the sounds of a crying baby up in the parking lot. And we get all of that sound. It might be an hour or an hour and a half. And we bring it back to the studio and we edit it down. And editing, Melody...

is a lot of fun. Yes, it is. You get sound files. We've talked about the sound, how a computer can show you a visual representation of the sound. Well, we cut it down so that we get the best parts for you to hear.

And then all the other stuff goes into sort of a little digital garbage can. I like to call it a recycling bin. There you go. But we get to do a lot of fun things with that. We get to take out words. We can rearrange sentences. We could speed up sound if we wanted to. We could slow it down. We could put it in reverse. But the more fun part is creating different layers of sound. So we could take the sound right now that we're recording in a studio and we could make it sound like we're at the beach or we're at the zoo.

Or in a busy city. Now, I will say one thing, which is that Melody and I both also work in news. And when you're working in news and in reporting, you never make it sound like you're somewhere that you're not. Because part of the job of being a news reporter or a news person is to present the truth. So all the fun things that you can do with audio, we actually typically don't do that on. But why? Because we want you to hear truth.

real sounds and a real representation of the world. But you can do all of this fun stuff with editing software.

So it all gets mixed together. We call that mixing. And it's when you get all of these sound files all arranged on your computer together. And then you turn it into one sound file. And then we have to send it to you. And so the way that we send it to you is over the Internet. Yeah. So it's actually not using the radio signals we talked about earlier. It's a different technology, but it's a similar idea. It's a way to get sound from us directly.

to you. And remember, Melody, we were talking about the difference between podcast and radio. Some of it is technological, but the other part is about the end user. It's about the listener, you.

One other thing that's really interesting about podcasts is that anyone can create them. To be on the radio is really hard because, as you heard Joe talking earlier, you need radio towers, you need a radio station, you need all of this equipment, and it's very expensive. But to be a podcaster, most people have the technology now in their own homes or sometimes even in their hands if your adult has a phone, and you could actually be a podcaster yourself. Right.

And all they have to do is create an audio file and they put it on a website that hosts it. And then anybody who wants can find that and listen to it. So if you were really interested in cats, you could make a podcast where every episode is about a different kind of cat. And there's somebody else out there in the world who wants to listen to millions of episodes about cats. That's the really cool thing about making podcasts.

In fact, there are a lot of kids making their own podcasts now. Maybe you listen to some of them. We'd love to know what kind of podcast you would make if you were a podcaster. Or maybe you're already making one. Send us a link so we can listen to your episodes. And podcasts are useful because you can listen to what you want when you want to listen to it whenever you want. And you don't have to wait until a certain time of day to catch your favorite radio program the way people had to in the past. Gosh, those people who are 40, 50, 60 years old must have been a hard life. Really. Yeah.

That's it for this episode all about sound. We loved having the opportunity to talk about something near and dear to our hearts. We love working in audio. If audio production is something you're interested in or you want to start your own podcast, have an adult go to butwhykids.org and we'll have some resources there that you can explore. We'll even have a picture of what the sound waves in this episode look like.

But Why is produced by Melody Beaudet. Melody, it was so fun to have you host this episode with me. It was fun to be here. And me. I'm Jane Lindholm, and we make it at the studios of Vermont Public Radio. Our theme music is by Luke Reynolds. And, you know, there are a lot of people who work in radio and podcasting here at VPR who are never on the air. So a shout out today to Jonathan Butler, Noah Villamarine-Cutter, Meg Malone, John Van Hoosen, Scott Finn, and

And special thanks to Chris Albertine and Joe Temecki who joined us on this episode. We'll be back in two weeks with an all new one. Until then, stay curious. I like that.