 Welcome everyone to the first store for today. If, like me, you didn't sleep a lot yesterday night, well, I hope to keep you awake, and as you know, I'm using a microphone to do that. And my talk is about sound, so I had to show you something interesting. So my name is Jean-Lucca Memoli. It's an Italian name, as you might guess, from my actual accent. And I've been working in acoustics for, well, now for 10 years. I've been doing all strong, constrained stuff. I've been doing noise. I've been doing soundscapes, which is the word that people use to describe how they perceive sound, and how we design space around it. I've been a bubble scientist for now, for 12 years, and now I'm working on metamaterials. My talk, then, comes from my experience as an amateur testing. So when I direct a play, I consult to my light person, can I please have a spotlight? Or can I please have a light there? Can I have a diffuse light? Can I have a light which follows the character? I cannot do that with sound. With sound, I have to rely on speakers, which are placed in strategic positions by people who know what to do that. You can see that there is an array for a concert. What we do is we design goals that everyone in the room hears the same sound. So let me show you something from my days as a consultant. Imagine this is a theatre, and what you see there is the sound which is going on, and as it goes on, you see the waves which propagate, and suddenly everybody is filled with sound, the same sound for everyone. But that's not what we do with light. When it doesn't pick up, of course. So my days, can we get the same? Can we do the same with sound that we do with love? So that's my outline of my talk, and I start to read what we can do, and what they do in updates, and eventually I tell you about my ideas and the exciting opportunities that they offer to us. You can see some stuff here, and they might need some volunteers in the audience to have a deal with my talk. So what can we do today? So what you see here are two pictures about Dolbydweith, so surround sound. Now what I would like you to get from your seats in the audience is how many speakers do you need to do a five plus one surround system in a home? So you guess? Well it's written there, isn't it? So what about if you go to the cinema, how many speakers can you actually get to have an experience in a nine-mark? Any guess? Forty. Forty. Any other number? Twenty-two. Twenty-two. Forty-two is giving you the answer, isn't it? Say, normally you can reach up to 64 speakers, and even in that case, the feeling that you have is great, but it's an illusion. Sound is not really around you. You are tricked to believe that. But there are other applications where you need a lot of speakers to control the shape of sound. So one of that is diagnostic. So we are all familiar with the idea of using ultrasound to see babies in the womb of mum. And now people are using ultrasound also to cure and to destroy tumours. And this is an image from destroying prostate cancer with ultrasound. So how many speakers, or chasaric speakers, do you need for this application? What about the first number? How many? Sixty-one. Any other? One? Okay, so you need about 100 speakers to get an effect of a beam which gives you an image on the screen. Here, the number increases. So all of these technologies want in the same way. You have a lot of speakers and a computer attack which controls them like the director of an Oxford conductor, does with your orchestra. So the conductor tells them you play, no, it's your time to play, no, it's your time to play, no, it's your time to play. Each of them is tuned to a note, and in this way, they get a shape. What I just described is called digital signal processing. And, well, the simple way is in that but you also see that in front of that flow there is something which is labelled an acoustic lens. So there might be then a way to improve the performance of these devices. But my goal today is to demonstrate to you that maybe in a short future all these devices will be obsolete. And we can do sound control in our car. So to do that, I use a case study which is levitation. So acoustic levitation has been around for a while. You cannot levitate men, unfortunately, because you wouldn't need the power supply that's of a big cold plant. But you can levitate polystyrene beads. So what I'm doing here is I'm getting some polystyrene beads which of course, since I'm live, they're not getting on the object here, on the scoop. So what I do is I take my polystyrene beads, I put them here, and what I have here is a wave which is trapped between two sets of speakers, which are sonic speakers, and that's why you don't hear them. And we're in the digital house clipping for that. And I know that's the people who are cleaning this room lately after that. But eventually, when it works, something levitates. So let me show you the video. And then you can come and try. I had someone try that earlier to check that it was working. Well, you can try it later. So what you can do with the time for the speakers, you can move objects in media. And so you can make parts, you can make figures, you can make shapes, you can transmit information. And then you can load two of them together and move them around. So this work was done in the University of Bristol from my former supervisor. You can see it's quite cool. What you really want is not that. What you really want is this. What you want is to control in remote with sound something far away. What you want is the possibility of dragging something from you or sending it away. So the first step in that direction comes here where you have levitation on only one side. I don't have this demo. What you see is that you create basically a shape. So you create a shape, a cup, which takes the particle and keeps it afloat. So the problem with these technologies, so before we can actually use them, is that the cost ramps up very quickly. So transducers are very easy. Speakers are very easy to control, but you need a lot of them if you want to have a control, a special control to the seat of these audience, for instance. And then there is a physics limit because speakers are big. They need to be big because sound as a wavelength, which is quite big. And so if they are not big, then they don't respond to buses. So there is a technology limit in making speakers and the same applies to ultrasonic speakers. But in optics, they don't do that. What they do since the time of Archimedes is they use lenses. And what we do for those lights is we use reflectors which change the shape of the light. We use lenses to... We put objects in the middle between the source, so the light and myself, to change what happens to the light. So why can't we do that with sound? So these devices have been around for a lot of time for light. So much that actually if you take a £5 note, you'll find anologram in it, so the big Ben. So we normally use these things every day and night. Why can't we use them for sound? I think we can use them for sound. Let me show you what you can do now without going that direction, but the other direction, this way. So that is the example of a lighthouse. And what they do is they use what is called a Fresnel lens to send light away, long, long distances. And what you see down there is a design, so it's measurements that I recently did with my special lenses for sound that project the sound of a speaker from here to the tent down there in workshop one, I believe. All of this is done with metamaterials. So what is a metamaterials? Metamaterials are devices which are engineered to have a special property. Well, saying that, I said nothing, because with these words I can describe everything. I can describe a guitar, I can describe a shredder diffuser, which is the one that you see on top and that is used at concert halls. I can describe a sponge. The trick is that these materials, and I have some of them here, 3D printed, can be made of any actual material, but you can shape them inside so that the sound gets delayed in this particular case. How do they look like? Well, this is a big version, so this is a big lens, and this covers the highest note of a piano, quite bulk, isn't it? But also you can have them in the shape of sodacans. So this was the first lens that I saw. This is done with the trick that you use to make a xylophone with glasses, where you fill the glasses with different depth or liquid, and in this way they send the sound around, you can see the speakers at the corners there, and they created a spot. Now what was my contribution to this is that I found that actually you can do this in a much simpler way and you just need Lego-like bricks to do this. So instead of taking the cans and filling them every time, you just need 16 types of cans or shapes to give you a control on sound beyond what you can perceive. Just like you need 26 letters to make any word. So how do they work? What they do is they... Well, I have a microphone here, let me go closer. So how do they look like? They are like objects where you can change the size of the maze inside, and you can have a go at this after my talk, and by changing the size of the maze, you change the time the sound passes inside, like in that picture, and you see that depending on the length of the maze, you change a different delay. So what you see in this picture is a wave, which takes more and more time to reach this point here. So in this way, you control phase, just like you do that with a digital processing, but in a passive way. So what you can do with it then is by using these bricks, you can do, obviously, levitation. So what that one is... Oh no, I went too quick. So let me try this one first. So these are the bricks, and you can hear the go-getters on the background probably. That's my son who is keeping himself occupied while I talk to you, and we use 16 of those bricks, and by putting them together, and you can see that I'm doing that very quick in this movie, it doesn't take so, it's not so quick in real life, what you can do is you can make patterns. And so with these patterns, two of them, I can put them together, and I can make them to levitate, which is what I needed. So with a speaker, a general speaker, and two objects that I 3D printed, I can do levitation. And if I can do levitation, I can do much more because I can do a lot... Levitation is a way for me to show you that I have control. It's a way for me to show you that I have the power. But in reality, levitation is something that might be... Well, it managed to bring me on ITV to levitate food, but it might be far from the real application, unless we can control it so well that we can use this type of control into the body, for instance, to deliver medicines. But since this is an ICT friendly community, let me tell you that you can do more. Just like suppose you don't have space to have, or you don't want to print 16 types of bricks, what you can do is you can use techniques to use less of them. And these are very similar to the one you use in compressing images, in doing a JPEG, for instance. And in this way, I'm using less of them, 11, if I remember correctly, in this one. And still, I can get levitation. And if I can go further, I can then levitate with just eight bricks. Which means that if you can be clever, then given a space and some requirements on the sound that you want to control, then you can transform one of this, which is bulky, into one of those. And they have the same effect on a normal speaker. Now, what's the problem? The problem is that the advantage of the problem is that at the moment the limit is how small you can make this with 3D printing. And the problem is that the other bit is, at the moment compared to a lot of speakers controlled electronically by processing, is that this solution is static while the others are dynamic. But we learn from optics that turning lenses into something dynamic is not too difficult. You can use that for headsets in 3D displays. So let me go to applications. Because I can see that probably you're already wondering what we are doing here. Why are we wasting my time here at 10 o'clock? So this was Iron Man. And so as a scientist, I feel that I always try to catch up with Hollywood. That is one of my challenges at the moment. And what you see here is that soon to become Iron Man is trying to find vibranium in a map. But there is something in this which is implicit. So it's not just an hologram there which it can pass through. It's not just telling the computer, please spin. It can do more than that. It can actually, and this is even clearer later in the movie, you can actually touch the stuff. So he is doing what technically, so did you see that? Spin it just by touching. So he knows where to put his hand. So what's up there? So this is called technically media optics. Can we do that already? Yes, we can. With speaker arrays. So this is a company in Bristol which sells devices which transform and gives you shapes in media made of sounds. So how does it work? You have a lot of speakers and if they send the sound at the same time on your hand you feel nothing. But if you time that with different delays then this eventually creates a spot on your hand and you feel something. And if you create many spots at the same time then you can create shapes. And so then in this case you can then create the outside of a sphere. So can I do that with metamaterials? Yes I can and I can do much more. Because with metamaterials I can create shapes which are more complex all at one time. So we have a demo here, I have a demo here where you will be able to touch sound if you come a bit later. But what I want to show you and that's the demo we will do now is this. So this is again catching with Oliver. This is Minority Report 2002. Now if we had the audio we could be hearing that Tom Cruise is fast around to recognize and see at first. So that's personalised metamaterials. So that means to down just for a person with spots. OK. So at the moment this is usually a show and let me show you how it works. So you have a speaker. So this is one made by us at Suset. So in ours. And let me show you how it works. Let me use some of the speakers. This is something which is already out there. What you can do with metamaterials. So I do that instead of doing this. So can you still raise your hand if you hear something. So now I do the energy change. So the people here start raising their hands when they were not before. So what I did is I put something in front and I changed the direction of sound. And I can shape this in a way that actually goes around this pillar here and be a scenario of silence in the middle in sound of a rap. Now imagine you are in a distance and you are dancing and eventually there is a space in the middle of the dance floor where you can talk and decide that side you go. Or you can also go to the bar and finally talk to the barman and get yourself understood and maybe make an order without being so silly. Or at least what we hear in Australia is yes this year in Las Vegas you can be in the car and you create zones. So you have a speaker, so the driver which is listening to the GPS and the passenger who is listening to the music and my son on the back who is listening to the sound of his CV is and we are not hearing it in charge. So it's a world where you have perfect control to the seat level or sound without... So if you push this pillar like us physics is also works the other way around you can then cancel the sound inside. So this was the window and there are a lot of companies that are trying to start and this is the window which lets the air through but not cancel the sound within the system language. So imagine now you have a reconditioning unit on that side you will not hear it. But you will see that. So where we are going to do this? When you see that, it's a way of seeing it. It's a way of going to a world where we will not use headphones anymore. Where we will have 3D shapes on our phones that you can touch. Where instead of having personalised rings for my mum I can have a shape where I can feel that it's my mum for it and I can decide on what's on it. Or we are going to a world where if you are sitting on a sofa I can send Spanish to that side and English to that side and you can learn a language just by changing seats on a sofa. So what we are doing is we are going to give you and we are reaching a world where we have control sound just like we have on a live CD which as you can see is quite cool today. But change the way we think sound. The moment sound is something that either we have or we don't. Either we have it on our headphones or we don't. We are changing sound in a way that there will be just the right sound for everyone. For medical applications, for concert halls, for controlling your cars in your sofa, in your sitting rooms, in your kitchen. So we are going beyond what we can do with a lot of our speakers through materials that we engineer specifically to do that. So thanks for your attention and I hope you enjoyed my talk and we are recruiting for this if you are interested and otherwise please pass the device. Thanks a lot.