초음파 스피커: 지향성 사운드 기술 설명

### 초음파 오디오 웨이브: 지향성 사운드 기술의 미래
* 🔊 오디리 모델 B 스피커는 **초음파 음파를 사용하여 헤드폰 없이도 프라이빗한 청취 환경**을 제공하는 지향성 스피커입니다.
* 👂 초음파는 일반적으로 사람이 들을 수 없지만, **스피커는 초음파를 변조하여 초음파 주파수 내에서 가청 사운드로 인코딩**합니다.
* 🎯 스피커는 **15° 퍼짐**으로 비교적 집중된 원뿔형 사운드를 생성하여 특정 영역 내에서 헤드폰과 같은 경험을 제공합니다.
* 🏞 ️ 평평한 표면에서 소리가 반사되어 여러 방향에서 소리가 나는 듯한 착각을 불러일으킬 수 있어 **유령의 집과 같은 창의적인 애플리케이션**에 이상적입니다.
* 🌐 **상업용 시설, 쇼룸, 박물관, 디지털 사이니지**는 이 기술의 주요 타겟 시장 중 일부입니다.
* 🎮 게이머에게는 자유로울 수 있지만, **높은 비용**으로 인해 개인용보다는 상업용으로 더 적합할 수 있습니다.
* 🚀 이 스피커의 제조업체는 비용 절감을 위해 노력하고 있지만, **실험에 관심이 있는 분들을 위해 이미 온라인에서 DIY 버전**을 제공하고 있습니다.
* 👂 스피커의 초음파 주파수는 **일부 개인과 동물에게 불편**할 수 있으며 장애물에 의해 쉽게 차단될 수 있습니다.

엘리야는 초음파 음파를 사용하여 개인 청취 구역을 만드는 매력적인 지향성 스피커를 발견합니다.

it's the weirdest thing. Elijah, can you hear this speaker? Yeah, I can hear it somehow. My microphone picks up nothing right next to it, but Elijah can hear it from down the road. Now, sound waves are always directional to a degree, but this thing is on a whole other level. Perhaps magic? Spoiler, no. The oddly model B uses ultrasonic audio waves, which you normally can't hear, and adds some special sauce to create a directional speaker that's designed to create a private listening zone, giving the user a headphone-like experience. Is that something people are asking for, and what are we giving up in return? Also, are there any fun, creative ways we could use this technology? Not sure, a few things, and yes, but before I tell you about them, Elijah needs to tell you about our sponsor. Hey there, you are Ridge. Upgrade your everyday carry with a Ridge wallet. Their new Ridge lights are just as functional and even more compact than before. Use our link and save 10% off your purchase and get free shipping with code Lonus to help you guys experience how

cool. This thing is we've set it up on a lazy Susan in an open area of our warehouse. Then all you got to do is pop on a pair of headphones and you'll be able to hear exactly what we hear with the help of our friend Steve Elijah hit [Music]. It that is so weird. It sounds like it's in the one ear and then it sounds like it's inside my skull and then the other ear and then it's gone and then because we've got flat surfaces here in the warehouse it actually bounces off of some of them and sounds like it's coming from completely different places. Now alongside the greatest song of all time you might have heard a slight buzzing or interference or Dropout sound. That's because the microphones are picking up some of those ultrasonic frequencies that I mentioned earlier but to most human ears it sounds as clear as any other speaker you'd find at the local Best Buy. How does this work and what makes it different from a traditional speaker in a traditional

speaker two things contribute to the audio that you hear: the amplitude, or how hard the speaker pushes against the air around it, determines how loud it is; and the frequency, which is how many of these cycles it completes per second, contributes to the pitch. Sound energy travels in waves, just like ripples in a body of water, meaning that when you make sound, anybody nearby can hear. Baby, no money, forget that melody. Now we can focus or aim it to a degree [Music], but because the wavelengths of audible sound are so long, the waves can travel through solid objects and even bend around corners. That's why I can hear this speaker pretty well from behind it. That's why these speakers use ultrasonic transducers instead, and I can practically hear you guys shouting lus. Humans can't hear ultrasonic frequencies; that's what makes them ultrasonic. And you're right, we can't. But thanks to some math that I don't understand now and probably never will, we can alter the amplitude and can modulate our

ultrasonic transducer array to encode audible sound within ultrasonic sound. Now, it took decades and the development of sophisticated computer simulations to go from the original theory to this point, but now that we're here, it flipping works. And because ultrasonic waves have much shorter wavelengths, they spread out far less, creating a relatively focused cone of audible sound. It's still about 15°, meaning that at a great enough distance, multiple people can hear it, but the effect in person is really trippy, not to mention a lot of fun. I'm in a position where it should be hard for anyone in the lab to see me, and I'm going to start up a Wan show. I thought someone was talking. I thought then I'm going to beam it around the warehouse and see what happens next. Target Logistics. I don't even know what this plastic is here for. It's clearly to prevent peep. Bad actors like you. Elijah's bringing a knife so we can control Logistics. Now we're going to

point it through the plastic. But first, we got to troll Elijah so confused. I can see Jamie. Okay, we're going to go for Jamie. We're going to go for Jamie. Okay, where the how they all find us immediately. Dang it. How'd you guys find us so fast? I heard through it earlier. Oh, dang it. Well, you win some, you lose some. Still a lot of fun. If we were smart and we really wanted to throw people off, though, we would use the effect where it bounces off of flat surfaces, creating a really weird effect where it sounds like it's coming from the Reflection Point rather than from the location of the speaker. Let me show you what I mean. Okay, Elijah, I'm straight at you. Yep, I hear it there, right there. Okay, what if I bounce it more times? I hear it right about there. Yeah, and it's super trippy. If I did not see you, I would think it's coming from the wall. Pretty wild, right? I mean, you'd think after a bounce or two, it would sound a lot farther away, but

ultrasonic waves don't attenuate nearly the way that audible waves do. So, whether I'm 10 ft away or 100 ft away, bouncing once or four times, it sounds really similar. The question now is, how far can we go? Well, based on what they saw in the intro, you're going to have to go a lot further than that, buddy. Alrighty, poor Elijah, he's getting his steps in today, boys. Most exercise I've done all year. How about now? Yeah, I can still hear it. How about now? No, I don't hear it. Oh, okay. How about if I aim it at you? It sounds the exact same. I hear it totally fine. Okay, keep going. Oh, oh my goodness. It's crazy to me how it's been sounding almost the exact same volume the whole way. How about now? I can still hear it. That is wild. We'll keep going a little bit more. Very faintly, but I can still hear it. That is very cool. We're almost at the end of our parking lot. Yeah, you can still hear it. I can

still hear it, yeah, and Andy can hear it from back there still. Oh yeah, going, there's a car in the way, but we are from end to end on the parking lot. Here's the Google Maps image to show you how far we are. Uh, let's see if I can still hear it. Do you hear it, Andy? I hear the truck. You might as well come back. Oh my God, this is freaking hilarious. They're standing in that corner with all those cars around them, and I'm kind of moving it around a little bit. It's got to sound like it's coming from like freaking everywhere. There was a split moment where all the way at the end of the parking lot, I heard like one or two notes at that distance. The issue you're running into is lining it up. Not even that, you can hear it anymore. That is super cool, but ultrasonic waves do have a downside. They get blocked very easily. You can see I'm sitting here chilling, listening to music. All I got to do is put this piece of

paper in front of it and H. And there's more. Remember that sound jammer that we bought on AliExpress? In theory, it can be deployed stealthily, but in practice, we found that people with sensitive hearing—sorry, sorry, sorry—can pick up those high frequencies. And because those ultrasonic frequencies need to be very high amplitude for the encoding to work, meaning they're very loud, it can create an uncomfortable feeling for some people and especially some animals. With all that cool how does it work stuff out of the way, what are these even for? I mean, I guess as a gamer, having a personal private listening cone without needing to wear anything on my head would be kind of liberating, but at this price? Yeah, it's more for commercial installations, you know, showrooms, museums, and the like. So you can step in front of an interesting piece, learn more about it, available now at LTT store.com, and when you're done, you walk away and the audio is gone. With a cleverly designed gallery, including soft surfaces to minimize reflections, you can offer a pretty

engaging experience for your customers or patrons. Oddly, the makers of this particular speaker focus on digital signage and advertising, but they also highlight some pretty creative uses, like this one integration in a playground haunted house. Pretty spooky. What's really cool is Oddly is working on cutting the costs, but if you don't want to wait, there's actually tons of videos online showing people building these speakers for themselves, including this one guy who actually made it look like a little gun to point at a target. I don't know, it's kind of cute, just like this cute segue to our sponsor. Thanks to Corsair for sponsoring this episode. Corsair Custom Lab allows you to create a gaming setup as unique as you are. Start with a product like their K65 Plus wireless keyboard and select from a variety of different themed keycaps to match your style. From there, you can add a mouse and a mouse pad to complete the look. Corsair handles all the heavy lifting for you. Just make your custom creation, and they'll build it and ship.

it right to you learn more at the link in the video description. If you guys did enjoy this video, go check out the recording Jammer video. That one was super cool as well and helped cover up some hot takes that lonus had.

Only 1 Person in the World Can Hear this Speaker

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지향성 스피커의 독보적인 기술

이색적인 모델 B는 초음파 음파를 사용하여 지향성 스피커를 만들어 프라이빗한 청취 공간을 제공합니다.

이 스피커의 독특한 디자인은 사용자에게 헤드폰과 같은 경험을 제공하는 동시에 소리가 평평한 표면에서 반사되어 다양한 청각적 인식을 제공합니다.

이 기술의 효과는 마이크가 초음파 주파수의 간섭을 수신함에도 불구하고 청취자에게 선명한 사운드를 제공하는 능력으로 입증되었습니다.

소리는 스피커의 진폭과 주파수에 의해 생성되며, 이 진폭과 주파수가 소리의 크기와 높낮이를 결정합니다.

가청 음파는 단단한 물체를 통과하고 모서리에서 구부러질 수 있지만, 사람이 들을 수 없는 초음파는 파장이 짧아 가청 음을 인코딩하는 데 사용할 수 있습니다.

초음파 트랜스듀서를 사용하면 가청음에 집중된 원뿔형 사운드를 구현하여 독특하고 몰입감 있는 청취 환경을 만들 수 있습니다.

이 스피커는 초음파를 이용해 소리를 평평한 표면에 반사시켜 친구들을 혼란스럽게 만들어 트립 효과를 냅니다.

거리와 바운스 횟수에도 불구하고 소리의 크기는 비슷하게 유지되어 위치를 인지하는 데 어려움을 겪습니다.

이 실험은 초음파의 고유한 특성을 보여줌으로써 멀리서도 초음파를 선명하게 들을 수 있게 해줍니다.

오디오에 대한 초음파의 사용과 영향

초음파는 주차장의 다양한 거리에서 소리를 들을 수 있는 독특한 오디오 경험을 만들어낼 수 있습니다.

하지만 초음파는 쉽게 차단되고 진폭이 커서 사람과 동물에게 불편함을 줄 수 있습니다.

이 기술은 주로 상업용 설치에 사용되며 헤드폰 없이도 프라이빗한 청취 경험을 제공합니다.

디지털 사이니지 스피커의 창의적인 활용

독특한 스피커 제작자는 디지털 사이니지 및 광고에 중점을 두고 유령의 집과 같은 창의적인 용도로 사용합니다.

그들은 비용 절감을 위해 노력하고 있지만, 온라인에는 비슷한 스피커를 직접 제작하는 사람들의 모습이 담긴 동영상이 많이 있습니다.

이 에피소드는 개인 맞춤형 게임 설정을 제공하는 Corsair Custom Lab의 후원을 받았습니다.