0:00:02 > 0:00:04RADIO: 'Today's forecast is cloudy but mild...'
0:00:04 > 0:00:09Imagine a world without the ability to capture or transmit sound.
0:00:09 > 0:00:13Every word we spoke would be lost forever. There'd be no phones,
0:00:13 > 0:00:16no radios, no rock concerts for mass audiences.
0:00:18 > 0:00:21So, how did we conquer sound?
0:00:21 > 0:00:24It was an unknown printer who created the first ever
0:00:24 > 0:00:30recording of the human voice, though no-one heard it for 150 years.
0:00:30 > 0:00:34It sounds kind of like a horror movie soundtrack, I have to say.
0:00:34 > 0:00:36And a beautiful movie star who helped give us
0:00:36 > 0:00:38privacy on our mobile phones.
0:00:39 > 0:00:41She'd rather spend the night at home reading
0:00:41 > 0:00:45Scientific American than going out to some glamorous party.
0:00:45 > 0:00:49These are classic examples of the kind of people who actually
0:00:49 > 0:00:51made the modern world.
0:00:51 > 0:00:54And their stories are probably ones you've never heard.
0:00:58 > 0:01:01They're hobbyists and garage inventors,
0:01:01 > 0:01:06maverick characters doing extraordinary things.
0:01:06 > 0:01:10What I love is that these pioneers didn't just give us mastery over
0:01:10 > 0:01:17sound, but they also set in motion an amazing chain reaction of ideas.
0:01:17 > 0:01:20Resulting in innovations that would go on to affect every
0:01:20 > 0:01:21aspect of our lives.
0:01:23 > 0:01:24From the world of work.
0:01:24 > 0:01:26TELEPHONE OPERATOR
0:01:26 > 0:01:27To race relations.
0:01:27 > 0:01:29TRUMPET PLAYS
0:01:29 > 0:01:31Saving lives.
0:01:31 > 0:01:33HEARTBEAT
0:01:33 > 0:01:34And changing our cities.
0:01:37 > 0:01:39I want to show how the link between all these apparently
0:01:39 > 0:01:44unconnected worlds starts with the unsung heroes of sound.
0:01:48 > 0:01:53All my career, I've been fascinated by ideas and innovation,
0:01:53 > 0:01:56from writing books about the great British innovators
0:01:56 > 0:02:00of the Enlightenment or the Industrial Revolution, to my work
0:02:00 > 0:02:03with Silicon Valley start-ups. And what I've learned about innovation
0:02:03 > 0:02:08is that the experiences of the past are still the best road map for our
0:02:08 > 0:02:13future, and that's why I want to tell you story of how we got to now.
0:02:28 > 0:02:30It's almost a sacred experience.
0:02:30 > 0:02:34The desire to capture and share another human voice.
0:02:37 > 0:02:41MUSIC: Habanera from Carmen by Bizet
0:02:41 > 0:02:46But the art and science of manipulating sound is
0:02:46 > 0:02:52actually an old story, one that takes us back to pre-historic times.
0:02:58 > 0:03:01Here, at the Arcy-sur-Cure caves in France,
0:03:01 > 0:03:06are traces of human activity over 30,000 years old.
0:03:08 > 0:03:12This is one of the most magical spaces I've ever been in.
0:03:12 > 0:03:16I'm standing just inches away from one of the very first
0:03:16 > 0:03:20traces of our desire to record our experiences.
0:03:22 > 0:03:25Researchers now believe that these caves were not just
0:03:25 > 0:03:29used by our ancestors to express themselves with their hands,
0:03:29 > 0:03:32but also with their voices.
0:03:32 > 0:03:37O-o-o-o-o-o-o-o.
0:03:37 > 0:03:41O-o-o-o-o-o-o-o.
0:03:43 > 0:03:49These incredible sounds are coming from Professor Iegor Reznikoff,
0:03:49 > 0:03:54a specialist in the sonic acoustics of ancient spaces.
0:03:54 > 0:03:58HE HUMS
0:04:00 > 0:04:02He believes it's no coincidence that
0:04:02 > 0:04:06the wall paintings are located in specific areas.
0:04:09 > 0:04:14It's a space for the eyes but it's a space also for ears.
0:04:14 > 0:04:18The more you have echoes, the more you have paintings.
0:04:18 > 0:04:23So the most acoustically interesting parts of the cave turn out to
0:04:23 > 0:04:26- be populated by the most images.- Yes.
0:04:26 > 0:04:29So they would sit in this space, look at these images,
0:04:29 > 0:04:32make these amazing reverberant sounds.
0:04:32 > 0:04:36- It was like the IMAX theatre of the Palaeolithic era.- Yes.
0:04:36 > 0:04:37Can I try the chanting for a second?
0:04:37 > 0:04:38Let me give it a shot, OK?
0:04:38 > 0:04:42You be my instructor, I've never done this before.
0:04:42 > 0:04:46O-o-o-o-o-o.
0:04:46 > 0:04:48- That sounded pretty good.- Yes. - I feel very manly when I do that.
0:04:48 > 0:04:50Try to push it out.
0:04:51 > 0:04:55- O-o-o-o-o-o. - O-o-o-o-o-o.
0:04:56 > 0:05:00Of course, Palaeolithic tribes couldn't record their own voices
0:05:00 > 0:05:05the way they could capture their visual experiences in painting.
0:05:05 > 0:05:09But by chanting and making animal sounds here, they were
0:05:09 > 0:05:14experimenting with a very early form of sound engineering using
0:05:14 > 0:05:20the natural acoustics of the cave to enhance and amplify the human voice.
0:05:23 > 0:05:27But over the next 30,000 years, not much happened.
0:05:27 > 0:05:32Sure, cave painting became Impressionism.
0:05:32 > 0:05:37But even by the late 1800s, our best attempts to share
0:05:37 > 0:05:42and amplify the sound of our voices basically amounted to...
0:05:42 > 0:05:45- HE SHOUTS:- ..shouting in big echo-y rooms!
0:05:47 > 0:05:52But in the late 19th century, that was about to change.
0:05:53 > 0:05:56Because an idea emerged that would transform everything,
0:05:56 > 0:06:02from how we respond to emergencies to how we build our cities.
0:06:02 > 0:06:06Thanks, in large part, to a failed invention from a forgotten
0:06:06 > 0:06:07Frenchman.
0:06:10 > 0:06:14In the middle of the 19th century, there's a new technology that
0:06:14 > 0:06:16has everyone excited.
0:06:16 > 0:06:18Photography.
0:06:18 > 0:06:20It's a medium that allows us
0:06:20 > 0:06:24to go beyond the painted impression of the world
0:06:24 > 0:06:31and for the first time to capture a mirror image of our lives.
0:06:37 > 0:06:40One instant convert to photography was a young,
0:06:40 > 0:06:45would-be inventor called Edouard-Leon Scott de Martinville.
0:06:47 > 0:06:51Scott saw how photography was able to freeze time,
0:06:51 > 0:06:55to immortalize what we could see, and this got him thinking.
0:06:56 > 0:07:01Scott is a printer by trade, so it's his job to reproduce
0:07:01 > 0:07:04and share the written word.
0:07:04 > 0:07:07He starts to wonder, what if there were a device that could
0:07:07 > 0:07:09capture the spoken word?
0:07:09 > 0:07:12A kind of camera for the ear and not the eye.
0:07:15 > 0:07:20Scott writes, "Will one be able to preserve for future generations some
0:07:20 > 0:07:25"features of the diction of those eminent actors, those grand artists
0:07:25 > 0:07:30"who die without leaving behind them the faintest trace of their genius?"
0:07:34 > 0:07:40To make this high-minded dream a reality, Scott has a brilliant idea.
0:07:40 > 0:07:43Just as the camera creates images by mimicking the function
0:07:43 > 0:07:49of the eye, Scott plans to build a device that mimics the human ear.
0:07:49 > 0:07:53Recording the vibrations caused when sound waves reach our eardrum.
0:07:58 > 0:08:03Today, the results are held in the Academy of Sciences, in Paris.
0:08:05 > 0:08:10OK, so here's Scott's actual hand drawn design for a contraption
0:08:10 > 0:08:12he calls the phonautograph.
0:08:12 > 0:08:15It's basically a device for visualising sound.
0:08:16 > 0:08:21You vocalize into a funnel with a thin membrane at the narrow end.
0:08:21 > 0:08:25Sound vibrations trigger a needle that makes lines on paper
0:08:25 > 0:08:29blackened with soot, wrapped around a spinning drum.
0:08:32 > 0:08:34And this is the result.
0:08:34 > 0:08:38Scott called it a phonautogram.
0:08:38 > 0:08:42It's impossible for me to overstate the importance of this document,
0:08:42 > 0:08:46because these squiggly lines represent the very first
0:08:46 > 0:08:48audio recording.
0:08:51 > 0:08:55For the 100,000 years since language developed, every word ever
0:08:55 > 0:09:00spoken by anyone was immediately lost to the air.
0:09:00 > 0:09:03But finally, thanks to Edouard-Leon Scott,
0:09:03 > 0:09:06we had a way to immortalize the human voice.
0:09:09 > 0:09:12It was an epic achievement.
0:09:12 > 0:09:15So why has nobody heard of this guy?
0:09:15 > 0:09:18Because, unbelievably,
0:09:18 > 0:09:22Scott's design was missing one crucial feature -
0:09:22 > 0:09:23playback.
0:09:26 > 0:09:27Isn't that crazy?
0:09:27 > 0:09:29I mean, it's a little bit like inventing the car
0:09:29 > 0:09:32but forgetting to add the feature where the wheels turn.
0:09:32 > 0:09:37'In 2008, audio historian David Giovannoni discovered
0:09:37 > 0:09:41'a series of Scott's phonautograms in the Paris archives where
0:09:41 > 0:09:43'they'd languished in obscurity for years.'
0:09:45 > 0:09:50Why do you think that key final feature was missing from his plan?
0:09:50 > 0:09:52Well, a couple of things here.
0:09:52 > 0:09:54The phonautograph was ahead of its time.
0:09:54 > 0:09:56I mean, way ahead of its time.
0:09:56 > 0:10:01Scott's singular contribution to the science of acoustics was to
0:10:01 > 0:10:05take sounds out of the air, write them on a piece of paper
0:10:05 > 0:10:10automatically - the phonautograph. And he thought, "Well, now that
0:10:10 > 0:10:15"I have a visual representation of the sound, if I could just learn to
0:10:15 > 0:10:18"read these squiggles and interpret them and know what was said."
0:10:18 > 0:10:20Did he try? Did he spend a lot of time trying to?
0:10:20 > 0:10:22He did, and others did.
0:10:22 > 0:10:26But he quickly found out that it was really hard to do.
0:10:26 > 0:10:30Giovannoni and his colleagues created history by using new
0:10:30 > 0:10:35software to translate the squiggles into audible sound.
0:10:35 > 0:10:36For the first time ever,
0:10:36 > 0:10:39Scott's recordings could be played back to the world.
0:10:41 > 0:10:45Edouard-Leon Scott himself, the inventor, sitting in his room
0:10:45 > 0:10:51in Paris, April 9th 1860, and he's turning the crank, he's singing
0:10:51 > 0:10:56slowly, carefully, he's probably watching these squiggles being made.
0:10:57 > 0:11:02These are humanity's first recordings of its own voice.
0:11:02 > 0:11:05OK, so you've completely whetted my appetite here.
0:11:05 > 0:11:08I want to hear the actual recording. Can we do that?
0:11:08 > 0:11:09- Cool, let's hear it.- OK.
0:11:12 > 0:11:13CRACKLY RECORDING
0:11:25 > 0:11:28It sounds kind of like a horror movie soundtrack,
0:11:28 > 0:11:31I have to say. I mean, appropriately, it sounds ghostly
0:11:31 > 0:11:34and here we are, we're bringing this voice back from the dead.
0:11:34 > 0:11:37He didn't send his voice a great distance,
0:11:37 > 0:11:41but he was the first human being to send his voice into the future.
0:11:41 > 0:11:46- Right.- Over time, not just distance, and that's the ghostly part.
0:11:46 > 0:11:51Because once you've fixed the voice, it does become a ghost
0:11:51 > 0:11:54and ghostly after the maker has gone.
0:11:59 > 0:12:02Tragically, Edouard-Leon Scott could never convince
0:12:02 > 0:12:06anyone of the importance of the phonautograph.
0:12:06 > 0:12:09He even wrote a book advocating its merits, but no-one listened.
0:12:13 > 0:12:16He lived out his years as a librarian and bookseller
0:12:16 > 0:12:20and died receiving no acclaim for his remarkable invention.
0:12:25 > 0:12:31As a commercial proposition, the phonautograph is a complete failure.
0:12:31 > 0:12:34But Scott's device will ultimately
0:12:34 > 0:12:39succeed as a kind of inspiration that spreads around the globe.
0:12:39 > 0:12:43Because now, his invention is about to trigger changes in society
0:12:43 > 0:12:46that go far beyond recorded sound.
0:12:48 > 0:12:52The phonautograph has a ground-breaking legacy.
0:12:52 > 0:12:54It was the vital trigger for not one,
0:12:54 > 0:12:57but two inventions which transformed our lives.
0:12:59 > 0:13:04In 1887, across the Atlantic, American Thomas Edison patents
0:13:04 > 0:13:09the phonograph - a machine that allowed us to finally defy time.
0:13:09 > 0:13:12Now we could not only capture the human voice,
0:13:12 > 0:13:15but we could also play it back whenever we liked.
0:13:18 > 0:13:21But the second invention is even bigger
0:13:21 > 0:13:24and will completely revolutionise the way we communicate.
0:13:26 > 0:13:29A man experimenting with Scott's phonautograph
0:13:29 > 0:13:33discovers that the process of recording sound can be reversed
0:13:33 > 0:13:35and that sound vibrations can be turned back
0:13:35 > 0:13:37into their original state.
0:13:40 > 0:13:45And so the human voice could be sent along a telegraph wire.
0:13:47 > 0:13:50Alexander Graham Bell had just invented the telephone.
0:13:53 > 0:13:55It catches on like wildfire.
0:13:55 > 0:13:59By 1904, there are over 6,000 independent phone companies
0:13:59 > 0:14:03in America and eight million kilometres of telephone wire
0:14:03 > 0:14:04connecting us all.
0:14:05 > 0:14:09TELEPHONES RINGING
0:14:14 > 0:14:18It's hard to imagine it now, but just over a century ago,
0:14:18 > 0:14:23the idea of our voice extending beyond the range of natural
0:14:23 > 0:14:27earshot would have been almost unthinkable. I mean, think about it.
0:14:27 > 0:14:30I'm here in London and just by dialling a few numbers
0:14:30 > 0:14:35I can hear the voices of my family, an ocean away.
0:14:35 > 0:14:38It's one of those miracles of everyday life that we're too
0:14:38 > 0:14:40quick to take for granted.
0:14:40 > 0:14:44But the telephone would do far more than just transform how we
0:14:44 > 0:14:46talk to each other.
0:14:48 > 0:14:52Within a few years of its invention, telephone switchboards create
0:14:52 > 0:14:55a revolution in job opportunities for women.
0:14:57 > 0:15:01The telephone collapses distances, emergency services can now
0:15:01 > 0:15:05respond much faster to alarms raised by phone calls.
0:15:09 > 0:15:13And as customers can now communicate easily with businesses many
0:15:13 > 0:15:17kilometres away, the need for a shop front in every town becomes
0:15:17 > 0:15:19less important.
0:15:19 > 0:15:21Businesses begin to consolidate
0:15:21 > 0:15:25and cluster in the booming cities, building upwards.
0:15:29 > 0:15:32Now, you might think that the elevator was the key
0:15:32 > 0:15:37technology in building skyscrapers, but you could make the argument that
0:15:37 > 0:15:42the telephone was just as crucial in creating the modern city skyline.
0:15:46 > 0:15:51The phone bridged great distances between us.
0:15:51 > 0:15:55The next big challenge for sound was how to send the human voice
0:15:55 > 0:16:00out to millions of people - all at the same time.
0:16:00 > 0:16:02It would transform everything,
0:16:02 > 0:16:04from popular culture to organised protest.
0:16:06 > 0:16:09RADIO: 'Forecast is for sunny mild conditions.
0:16:09 > 0:16:12'Afternoon temperatures 60s to low 70s.'
0:16:12 > 0:16:15'KCBS News time, 9.28 first for traffic...'
0:16:15 > 0:16:20This is KCBS, America's oldest broadcasting radio station,
0:16:20 > 0:16:22based in San Francisco.
0:16:22 > 0:16:25It's been hitting the airwaves for a century.
0:16:27 > 0:16:29We're like a cat, we're in about our seventh life now, we've been
0:16:29 > 0:16:32pronounced dead so many times we've forgotten how many times.
0:16:32 > 0:16:37'I'm speaking to news anchor Stan Bunger, on air!'
0:16:37 > 0:16:39So this is actually an historic radio station,
0:16:39 > 0:16:42there's an important history to what happened here.
0:16:42 > 0:16:43It happened really fast,
0:16:43 > 0:16:46I mean, very shortly after they started these transmissions
0:16:46 > 0:16:50in San Jose, they realised that lots of people were hearing it.
0:16:49 > 0:16:53Within a seven-year period, 60% of the families in the United States
0:16:53 > 0:16:54bought a radio set.
0:16:54 > 0:16:57What do you think the cultural effects of that was of radio?
0:16:57 > 0:16:58How did it change the country?
0:16:58 > 0:17:01Well, think of it as the very first time in American history,
0:17:01 > 0:17:05and really in world history, that that many people
0:17:05 > 0:17:07could simultaneously experience something,
0:17:07 > 0:17:08you know, a radio programme.
0:17:08 > 0:17:10What's the effect of radio today?
0:17:10 > 0:17:12We have all these different technologies now,
0:17:12 > 0:17:15but radio continues to be a vital part of our culture.
0:17:15 > 0:17:18The reality is more people in the United States still use
0:17:18 > 0:17:21the radio every week than use the internet.
0:17:24 > 0:17:29This gigantic cultural force of mass news and entertainment would
0:17:29 > 0:17:35owe a great debt to one of the most error-prone inventors in history.
0:17:35 > 0:17:39In 1900, Lee de Forest, a young, would-be inventor,
0:17:39 > 0:17:43is broke and desperate to make his mark on the world.
0:17:43 > 0:17:45He writes to his mother,
0:17:45 > 0:17:49"The only footprints I will leave will be my inventions."
0:17:57 > 0:17:59De Forest dreams of transmitting
0:17:59 > 0:18:03and receiving the human voice, not with wires like the phone,
0:18:03 > 0:18:07but invisibly, using electromagnetic radio waves.
0:18:09 > 0:18:12The idea of radio communication has been around for a while,
0:18:12 > 0:18:15but only very weak signals could be sent.
0:18:17 > 0:18:20The lack of amplification was a massive problem.
0:18:24 > 0:18:27In 1903, de Forest thinks that the solution to delivering
0:18:27 > 0:18:31a powerful radio signal to millions of people can be
0:18:31 > 0:18:34found by experimenting with gas and electricity.
0:18:38 > 0:18:41After three years of frenzied activity,
0:18:41 > 0:18:45he comes up with this strange object.
0:18:45 > 0:18:49It's a gas-filled bulb with three electrodes designed to
0:18:49 > 0:18:51amplify radio signals.
0:18:51 > 0:18:54He calls it the Audion.
0:18:56 > 0:19:00The initial tests of the Audion are very encouraging.
0:19:02 > 0:19:05De Forest plans a grand public demonstration to
0:19:05 > 0:19:07showcase his marvellous new invention.
0:19:17 > 0:19:22On January 13th, 1910, at the New York Metropolitan Opera, de Forest
0:19:22 > 0:19:26hooks up a telephone microphone to a transmitter on the roof.
0:19:28 > 0:19:32To broadcast his beloved opera for the first time.
0:19:32 > 0:19:35MUSIC: Habanera from Carmen by Bizet
0:19:35 > 0:19:38Anticipating wonder from his audience,
0:19:38 > 0:19:42de Forest invited hordes of reporters and VIPs to listen
0:19:42 > 0:19:47to his radio receivers scattered all around the city.
0:19:47 > 0:19:51WOMAN SINGS AN ARIA
0:19:51 > 0:19:54De Forest imagines a wave of invisible notes
0:19:54 > 0:19:56flying above the city.
0:19:57 > 0:20:01He sees it as a triumphant moment in his career, calling himself
0:20:01 > 0:20:06the Father of Radio, and he tells the New York Times,
0:20:06 > 0:20:09"I look forward to the day when opera may be brought
0:20:09 > 0:20:10"into every home."
0:20:14 > 0:20:17But the thing is, no-one is impressed with the historic
0:20:17 > 0:20:19broadcast.
0:20:19 > 0:20:24Because, while de Forest has promised his listeners this...
0:20:24 > 0:20:29SHE SINGS AN ARIA
0:20:30 > 0:20:33What they actually heard was this...
0:20:33 > 0:20:35MUFFLED AND DISTORTED MUSIC
0:20:42 > 0:20:46The broadcast was a disaster, the press laughed at him
0:20:46 > 0:20:50and later de Forest was even arrested for fraud,
0:20:50 > 0:20:53accused of overselling the value of the Audion to his shareholders.
0:20:57 > 0:21:00The truth is, the Audion just wasn't that good.
0:21:00 > 0:21:05And it did amplify radio signals, but not nearly enough...
0:21:07 > 0:21:10..to launch a broadcasting revolution.
0:21:13 > 0:21:18In 1913, de Forest sells the Audion patent at a bargain price to
0:21:18 > 0:21:19pay legal bills.
0:21:21 > 0:21:24It's snapped up by the R&D Department at AT&T,
0:21:24 > 0:21:27who discover something startling.
0:21:28 > 0:21:34What they find is that de Forest had been flat out wrong about almost
0:21:34 > 0:21:37everything he was inventing.
0:21:38 > 0:21:41But lurking behind de Forest's
0:21:41 > 0:21:47accumulation of errors, there was a beautiful idea waiting to emerge.
0:21:48 > 0:21:53He was actually on to something with his three-electrode design,
0:21:53 > 0:21:56but de Forest's big error was believing that
0:21:56 > 0:22:00the gas inside the Audion could amplify a radio signal.
0:22:03 > 0:22:08Over the next decade, researchers experimented with his basic design.
0:22:10 > 0:22:12They took the gas out of the bulb,
0:22:12 > 0:22:14and suddenly it worked a whole lot better.
0:22:17 > 0:22:21That was the birth of the vacuum tube.
0:22:22 > 0:22:27And now, a device conceived as a way to amplify sound,
0:22:27 > 0:22:31by a man who didn't even understand how his creation worked, turns
0:22:31 > 0:22:35into one of the most transformative inventions in history.
0:22:35 > 0:22:39The vacuum tube could boost the electrical signal of any technology
0:22:39 > 0:22:45that needed it, triggering an electronics revolution.
0:22:47 > 0:22:53Radar, television, VCRs, sound recording, amplifiers, X-rays,
0:22:53 > 0:22:57and microwave ovens all become commercially viable,
0:22:57 > 0:22:59thanks to the vacuum tube.
0:23:02 > 0:23:06But its first success comes in making Lee de Forest's dream
0:23:06 > 0:23:08a reality,
0:23:08 > 0:23:13as the vacuum tube powers the transformation of radio
0:23:13 > 0:23:16into a mass medium for popular entertainment.
0:23:21 > 0:23:25The ability to broadcast inside people's homes captures
0:23:25 > 0:23:28the country's imagination.
0:23:29 > 0:23:33By 1936, three quarters of Americans consider owning a radio
0:23:33 > 0:23:36a necessity, even in times of hardship.
0:23:38 > 0:23:44Radio quickly becomes a vital source of news and information, but it
0:23:44 > 0:23:49also creates a national passion for a new kind of music.
0:23:49 > 0:23:50Jazz.
0:23:50 > 0:23:53THEY PLAY: When The Saints Go Marching In
0:23:53 > 0:23:56Originating in New Orleans, jazz had been around
0:23:56 > 0:23:58since the turn of the 20th century.
0:23:59 > 0:24:01And it was more than just music,
0:24:01 > 0:24:04it was an African-American cultural movement.
0:24:07 > 0:24:10Not that anyone in white America knew much about it,
0:24:10 > 0:24:13because society was still heavily segregated.
0:24:17 > 0:24:20And now, thanks to radio,
0:24:20 > 0:24:25jazz can step out from the basement clubs and inner city ghettos
0:24:25 > 0:24:29and reach America's white youth, who can't get enough.
0:24:34 > 0:24:38As radio takes off, the intoxicating rhythms of jazz
0:24:38 > 0:24:41become the most popular form of music on American radio.
0:24:47 > 0:24:49MUSIC: Strange Fruit by Billie Holiday
0:24:53 > 0:24:57The heady sound of jazz is unstoppable and the music becomes
0:24:57 > 0:25:02a vehicle for African-Americans to share their experiences.
0:25:02 > 0:25:06Songs such as Strange Fruit by Billie Holiday reflect
0:25:06 > 0:25:12the terrifying realities of racism and segregation in America.
0:25:12 > 0:25:19# Black bodies swinging In the southern breeze
0:25:21 > 0:25:26# Strange fruit hanging From the poplar trees. #
0:25:28 > 0:25:31Strange fruit was the first recording that really spoke
0:25:31 > 0:25:34directly to the horrors of lynching and the abuses that
0:25:34 > 0:25:37African-Americans were subject to at any time.
0:25:37 > 0:25:38And so I think that kind of reality,
0:25:38 > 0:25:43that stark reality for many white Americans who maybe had never seen
0:25:43 > 0:25:46a lynching, maybe have heard faintly of it,
0:25:46 > 0:25:48it forces them to look at America as it is.
0:25:48 > 0:25:49Music historian
0:25:49 > 0:25:53Ray Briggs has studied the impact of jazz on American culture.
0:25:55 > 0:25:59That song particularly became like a mirror, I think, for a lot of people.
0:25:59 > 0:26:01This song actually speaks to my humanity
0:26:01 > 0:26:03and I see these people as being human.
0:26:03 > 0:26:05Maybe I've been wrong, maybe my parents were wrong,
0:26:05 > 0:26:08maybe they haven't understood it in a way that I understand it?
0:26:08 > 0:26:10So I do think that the technology allowing jazz to
0:26:10 > 0:26:13be kind of disseminated more widely definitely made it accessible
0:26:13 > 0:26:14to a lot of people.
0:26:14 > 0:26:17They may not have gone to a political rally.
0:26:17 > 0:26:18But they'll listen to a song.
0:26:18 > 0:26:21And so when those artists who understand that power begin
0:26:21 > 0:26:23to utilize it, they speak to, I think,
0:26:23 > 0:26:26the power of technology and the power of music, that those
0:26:26 > 0:26:30two things coming together are just beyond understanding.
0:26:30 > 0:26:32That's a fascinating point in the sense that technology is
0:26:32 > 0:26:34one of the first steps of integration, you're
0:26:34 > 0:26:38bringing these voices and this culture into a white household.
0:26:38 > 0:26:39Most definitely.
0:26:39 > 0:26:42The interesting thing about jazz, and any music for that matter,
0:26:42 > 0:26:43that once it enters your space,
0:26:43 > 0:26:46once it gets in your head, it becomes a part of you.
0:26:46 > 0:26:48If you like it, then it becomes something that you value.
0:26:48 > 0:26:52So then you think, "Well, this music then is made by these people,
0:26:52 > 0:26:53"then maybe they have value."
0:26:56 > 0:27:01Radio helped democratise America through entertainment.
0:27:01 > 0:27:05Martin Luther King would later say that, "Much of the power of
0:27:05 > 0:27:09"our freedom movement in the United States has come from this music."
0:27:12 > 0:27:15What's also amazing about the vacuum tube is not only did it help
0:27:15 > 0:27:19us share music, but it then revolutionized
0:27:19 > 0:27:21the very sound of music itself.
0:27:25 > 0:27:27What I really love about the vacuum tube is that it's such
0:27:27 > 0:27:29a versatile device that even
0:27:29 > 0:27:32when it malfunctioned, it still managed to change the world.
0:27:36 > 0:27:41In 1960, a bassist discovered that a faulty amplifier could cause
0:27:41 > 0:27:44distortion and create a whole new sound.
0:27:47 > 0:27:52And so, thanks to the sonic properties of a broken vacuum
0:27:52 > 0:27:56tube, discovered entirely by accident, by the mid 1960s,
0:27:56 > 0:27:59the sound of popular music had gone from this...
0:27:59 > 0:28:01CLEAR GUITAR MUSIC
0:28:03 > 0:28:04..to this...
0:28:04 > 0:28:06DISTORTED GUITAR MUSIC
0:28:21 > 0:28:25Distortion defined the sound of The Rolling Stones and Jimi Hendrix and
0:28:25 > 0:28:31The Sex Pistols and Nirvana, and without broken vacuum tubes the last
0:28:31 > 0:28:34half century of popular music would have sounded completely different.
0:28:40 > 0:28:43Thanks to our growing mastery of sound,
0:28:43 > 0:28:47life in the 20th century was getting a whole lot louder.
0:28:49 > 0:28:56It was creating an offensive new phenomenon - noise pollution.
0:28:58 > 0:29:02OK, so I'm here in New York City, it's still a very noisy place,
0:29:02 > 0:29:05but imagine what it would have been like in the 1920s,
0:29:05 > 0:29:09when amazingly enough, it was even louder than it is today.
0:29:09 > 0:29:11So what are the sounds we would have heard?
0:29:11 > 0:29:14We would have heard the sound of cars honking,
0:29:14 > 0:29:15just the way we do today.
0:29:15 > 0:29:17TAPE MACHINE PLAYS CAR SOUNDS
0:29:17 > 0:29:20But on top of that we would have also heard
0:29:20 > 0:29:23the sound of policemen directing traffic with their whistles,
0:29:23 > 0:29:26and trams and horses, everywhere.
0:29:26 > 0:29:28RECORDERS PLAY THE SOUNDS HE DESCRIBES
0:29:28 > 0:29:30And you would have heard the elevated railway, which
0:29:30 > 0:29:33was around us, making this huge noise constantly.
0:29:36 > 0:29:40We would have heard the whistles from the steam boats in the river.
0:29:42 > 0:29:46And of course this is the era of construction with the giant
0:29:46 > 0:29:52skyscrapers and so there's people building these huge buildings.
0:29:52 > 0:29:57And on top of that, the final straw for most New Yorkers,
0:29:57 > 0:30:01the newfangled inventions of the gramophone and the loudspeaker
0:30:01 > 0:30:04blaring from shop windows and people's apartments
0:30:04 > 0:30:06throughout the day.
0:30:06 > 0:30:09It would have been absolutely overwhelming.
0:30:09 > 0:30:11A CACOPHONY OF SOUNDS
0:30:18 > 0:30:21So, you can see why they called it the Roaring Twenties, right?
0:30:21 > 0:30:24I mean, we'd created all these technologies to enhance
0:30:24 > 0:30:27and broadcast the sounds we liked.
0:30:27 > 0:30:30But we were starting to realise that we needed other technology to
0:30:30 > 0:30:34measure, and even remove, unwanted sound.
0:30:34 > 0:30:39And that's where this guy comes into the story, Harvey Fletcher.
0:30:41 > 0:30:44Fletcher was a technical genius, a committed Mormon
0:30:44 > 0:30:48and an all-round do-gooder who believed in using his skills
0:30:48 > 0:30:51for the benefit of his fellow man.
0:30:51 > 0:30:55He'd spent years developing ways of measuring sound intensity
0:30:55 > 0:30:57and its effects on the human ear.
0:30:58 > 0:31:02Now, Fletcher was part of a growing number of people who felt
0:31:02 > 0:31:06that the noise of city life was just getting too overwhelming and that it
0:31:06 > 0:31:11was causing high blood pressure and anxiety and decreased productivity.
0:31:12 > 0:31:18And so, in 1929, he offers his services to the newly formed
0:31:18 > 0:31:20Noise Abatement Commission.
0:31:20 > 0:31:21This is an organisation that was
0:31:21 > 0:31:24so serious about combating noise, that they actually held meetings to
0:31:24 > 0:31:28measure and test the offensiveness of different kinds of car horns.
0:31:28 > 0:31:29PARP
0:31:29 > 0:31:30PIRP
0:31:30 > 0:31:31PARP
0:31:31 > 0:31:32PIRP
0:31:35 > 0:31:39But Fletcher's grandest experiment was his decision to create
0:31:39 > 0:31:42a kind of a roving noise laboratory.
0:31:42 > 0:31:44A truck loaded with cameras
0:31:44 > 0:31:46and state-of-the-art sound equipment that
0:31:46 > 0:31:50drove around New York City's nosiest streets taking sound measurements.
0:31:54 > 0:31:57The Noise Abatement Commission used Fletcher's newly invented
0:31:57 > 0:32:00audiometer to measure the volume
0:32:00 > 0:32:02and intensity of noise in New York City.
0:32:04 > 0:32:1140, 41, 42. Parkinson, make it 42.
0:32:11 > 0:32:16The noise in Times Square deprives us of 42% of our hearing.
0:32:18 > 0:32:21Their pioneering work helped establish the decibel
0:32:21 > 0:32:22as a unit of measurement.
0:32:24 > 0:32:26I'm standing with sound historian
0:32:26 > 0:32:30Emily Thompson on the corner of 34th Street and 6th Avenue,
0:32:30 > 0:32:33once the noisiest place in the whole of New York City.
0:32:37 > 0:32:39And this is one of the first times we've got
0:32:39 > 0:32:43a unit of measure of some sort for just ambient noise.
0:32:43 > 0:32:46We do. He considered this the first scientific investigation
0:32:46 > 0:32:49of city noise. Now, the unit was a little fuzzy
0:32:49 > 0:32:52actually, it wasn't standardised yet, it was very particular to
0:32:52 > 0:32:56this machine. In fact, it was called the Noise Unit.
0:32:58 > 0:33:01At what point do we start measuring in decibels?
0:33:01 > 0:33:05The decibel is defined in 1929.
0:33:05 > 0:33:07It kind of standardised the procedure,
0:33:07 > 0:33:11standardised their equipment and came up with a unit that
0:33:11 > 0:33:16represented the hugely varying energy difference
0:33:16 > 0:33:21from the faintest barely perceptible sound, which is zero decibels, to the
0:33:21 > 0:33:26point at which sound is really perceived more as pain than as sound.
0:33:26 > 0:33:29And that's around 120, or 130 decibels.
0:33:29 > 0:33:32We'll do a couple at this concert tonight.
0:33:32 > 0:33:34So we're standing at 34th and 6th here,
0:33:34 > 0:33:37what was the decibel reading have been like around 1930 for this spot?
0:33:37 > 0:33:41According to the Noise Abatement Commission, the average value
0:33:41 > 0:33:48here was approximately 74 decibels, and it got as high as 90.
0:33:48 > 0:33:5090. OK. You know, it's funny.
0:33:50 > 0:33:53I just happen to have here in my pocket a decibel reader.
0:33:53 > 0:33:57- What a surprise.- Yeah, it's weird. I just carry these around with me.
0:33:57 > 0:34:00We're going to get a reading here, right now.
0:34:03 > 0:34:06- That's interesting, it's, like, 64 or 65.- OK.
0:34:06 > 0:34:11So, you think about it, you say the average in 1930 was 74,
0:34:11 > 0:34:16going up to 90, so it's actually quieter now than it was in 1930.
0:34:16 > 0:34:18So it must have been incredibly loud here.
0:34:18 > 0:34:19I think so.
0:34:24 > 0:34:27Thanks to Fletcher and the Noise Abatement Commission,
0:34:27 > 0:34:30new codes and regulations are passed in New York City.
0:34:33 > 0:34:40Whistle blowing traffic police are replaced by traffic lights.
0:34:40 > 0:34:42The city begins handing out fines for playing
0:34:42 > 0:34:44loudspeakers too noisily.
0:34:44 > 0:34:46TRUMPETS PLAY
0:34:48 > 0:34:52The elevated railway is sent underground.
0:34:55 > 0:34:59And all across America, highways are soon built with walls
0:34:59 > 0:35:02designed to shield out noise from nearby homes.
0:35:05 > 0:35:09Modern offices are designed to absorb sound, minimise noise
0:35:09 > 0:35:11and protect workers' health.
0:35:13 > 0:35:17As sound-proofing becomes a new industry across the Western world.
0:35:17 > 0:35:19HUM OF CONVERSATION
0:35:19 > 0:35:21KEYBOARDS TAPPING
0:35:22 > 0:35:24PHONE RINGS
0:35:27 > 0:35:31We've gotten better and better at reducing obtrusive noise,
0:35:31 > 0:35:35but where do you go if you want to escape sound entirely?
0:35:37 > 0:35:42Behind these two huge doors is an anechoic chamber,
0:35:42 > 0:35:45one of the quietest places on the planet.
0:35:45 > 0:35:48I'm going to go in here, shut these doors and, for the first time
0:35:48 > 0:35:51in my life, experience total silence.
0:35:59 > 0:36:03This chamber is an extreme example of sound proofing.
0:36:05 > 0:36:09Anechoic chambers can reduce noise levels to minus 12 decibels.
0:36:09 > 0:36:12Humans can't hear anything below zero decibels.
0:36:19 > 0:36:23It is a really striking feeling. I mean, you know,
0:36:23 > 0:36:25you feel almost like you've got a cold
0:36:25 > 0:36:30and you're congested, just kind of losing parts of the hearing
0:36:30 > 0:36:33spectrum that you normally take for granted.
0:36:35 > 0:36:38Anechoic chambers are used to test hearing aids
0:36:38 > 0:36:42and evaluate the sounds emitted from electrical appliances.
0:36:42 > 0:36:47Chambers like these are also even used for astronaut training.
0:36:47 > 0:36:49Hello!
0:36:50 > 0:36:52Hello, can you hear me?
0:36:54 > 0:36:57I'm testing the acoustic properties of this space!
0:36:59 > 0:37:02O-o-o-o-o-o-o!
0:37:04 > 0:37:08The sound of clapping is just completely dead.
0:37:10 > 0:37:14After a while, the sound of complete silence becomes rather disturbing.
0:37:22 > 0:37:25What it is, you're used to having sound waves
0:37:25 > 0:37:28bombarding your ears all the time and when there's nothing
0:37:28 > 0:37:31there it just feels like something is wrong.
0:37:32 > 0:37:36Soon the only audible noises are the sound of your heart beat
0:37:36 > 0:37:38and breathing.
0:37:38 > 0:37:39HEARTBEAT
0:37:42 > 0:37:45The sensory deprivation inside an anechoic chamber
0:37:45 > 0:37:48is so disconcerting that if left too long inside,
0:37:48 > 0:37:50you might start to hallucinate.
0:37:56 > 0:37:59Anybody want to let me out?
0:37:59 > 0:38:00Anyone?
0:38:01 > 0:38:04Hello?
0:38:04 > 0:38:05Hello?
0:38:07 > 0:38:09BELL CHIMES
0:38:12 > 0:38:16So it turns out that, far from banishing sound entirely,
0:38:16 > 0:38:19we need some level of background noise to prevent us
0:38:19 > 0:38:21from going completely crazy.
0:38:25 > 0:38:28Of course, the sound you're most likely to hear on today's
0:38:28 > 0:38:33city streets is someone talking too loudly into their cellphone.
0:38:33 > 0:38:37I mean, if Edouard-Leon Scott could time travel to today,
0:38:37 > 0:38:41he would be completely amazed. Not only can we record our voices,
0:38:41 > 0:38:44but we can project them through space and have a private
0:38:44 > 0:38:48conversation with someone on the other side of the planet.
0:38:48 > 0:38:50So how did that come about?
0:38:52 > 0:38:55In the early years of radio communication,
0:38:55 > 0:38:57privacy simply didn't exist.
0:38:59 > 0:39:00All frequencies were open,
0:39:00 > 0:39:04so any transmission could easily be eavesdropped, recorded or jammed.
0:39:07 > 0:39:11Up until World War II, opposing armies assumed someone was
0:39:11 > 0:39:13always listening in.
0:39:15 > 0:39:19But then, an innovation comes along that changes everything
0:39:19 > 0:39:20and leads to one of the most important
0:39:20 > 0:39:23technologies of the 21st century.
0:39:23 > 0:39:27Only this innovation doesn't come from a corporate research lab
0:39:27 > 0:39:30or some struggling entrepreneur in a garage somewhere.
0:39:30 > 0:39:33It comes from a movie star.
0:39:35 > 0:39:42Back in the 1940s, Hedy Lamarr was one of Hollywood's biggest stars,
0:39:42 > 0:39:47described by the press as "the most beautiful woman in the world".
0:39:47 > 0:39:49She starred in films with Clark Gable.
0:39:51 > 0:39:55You are the first American I've ever met with a soul.
0:39:55 > 0:39:59And played Delilah in Cecil B De Mille's Samson And Delilah,
0:39:59 > 0:40:03the biggest grossing movie of 1949.
0:40:03 > 0:40:07But Samson was ensnared by the seductive beauty of Delilah.
0:40:07 > 0:40:09Daughter of hell.
0:40:09 > 0:40:13His lust became a trap which led to his downfall and capture.
0:40:13 > 0:40:17She was a screen goddess who landed all the top roles.
0:40:18 > 0:40:19But the thing is,
0:40:19 > 0:40:23Hedy Lamar's life outside the movies is stranger than fiction.
0:40:26 > 0:40:31Born in Vienna, Lamarr established herself in 1930s European cinema
0:40:31 > 0:40:35and married a wealthy armament manufacturer called Fritz Mandl.
0:40:36 > 0:40:42In 1937, she dumped Mandl and fled to America to find stardom.
0:40:44 > 0:40:47Lamarr signs a contract that brings her here,
0:40:47 > 0:40:49to what was then MGM Studios.
0:40:49 > 0:40:54It's a movie factory and it turns her into an icon.
0:40:54 > 0:40:57She's a rich and famous movie star.
0:40:57 > 0:41:00But despite all the success, Lamarr isn't happy.
0:41:04 > 0:41:09Because, you see, Hedy Lamarr has brains to match her beauty.
0:41:09 > 0:41:11She finds Hollywood dull and shallow.
0:41:11 > 0:41:15She'd rather spend the night at home reading Scientific American
0:41:15 > 0:41:17than going out to some glamorous party.
0:41:17 > 0:41:21Lamarr even becomes an inventor to kill downtime on the set.
0:41:21 > 0:41:26She comes up with innovations like a dissolving tablet that
0:41:26 > 0:41:28turns into cola when placed in water.
0:41:34 > 0:41:38But it's war, not boredom, that will spur Lamarr to change the world.
0:41:40 > 0:41:44As World War II rages, the US Navy are struggling to effectively
0:41:44 > 0:41:46use torpedoes against the Japanese fleet.
0:41:48 > 0:41:53Radio guiding systems can only use a single frequency, which has no
0:41:53 > 0:41:58privacy so it's easy to find, jam, and send the torpedo off course.
0:42:01 > 0:42:04Lamarr decides to help the US Navy strike back.
0:42:07 > 0:42:11Now, it might seem like a big leap from a Hollywood studio backlot
0:42:11 > 0:42:15to military hardware, but it turns out, from her
0:42:15 > 0:42:19marriage to the arms magnate, Lamarr actually knows a lot about
0:42:19 > 0:42:21cutting-edge weapons research.
0:42:21 > 0:42:24And she's got a brilliant idea.
0:42:24 > 0:42:29It's a remote-controlled torpedo, operated from a plane overhead,
0:42:29 > 0:42:33with, and here's the brilliant part, a frequency-hopping signal.
0:42:36 > 0:42:39Her vision is for both the plane
0:42:39 > 0:42:43and torpedo to synchronise continuous frequency changes,
0:42:43 > 0:42:46so the enemy can't intercept and jam the radio signal.
0:42:56 > 0:43:01But turning Lamarr's crazy idea into reality won't be easy.
0:43:01 > 0:43:06And that's where this guy comes in - George Antheil, an eccentric
0:43:06 > 0:43:09polymath who no Hollywood screenwriter could dream up.
0:43:10 > 0:43:14Antheil had been a US weapons inspector during World War I
0:43:14 > 0:43:19before becoming a renowned avant-garde composer.
0:43:19 > 0:43:22He was known as the bad boy of music.
0:43:22 > 0:43:25And just looking at these two smouldering faces, it wasn't
0:43:25 > 0:43:29surprising they were going to cook up something remarkable together.
0:43:33 > 0:43:37And so the glamorous movie star and the experimental musician,
0:43:37 > 0:43:41one of the most unlikely duos in the history of technology,
0:43:41 > 0:43:42put their heads together.
0:43:42 > 0:43:45And they come up with this...
0:43:45 > 0:43:46THE PIANO PLAYS ITSELF
0:43:51 > 0:43:55OK, OK, so it's not an awesome death ray or something like that.
0:43:55 > 0:43:58It's a player piano, it's actually an old piece of technology.
0:43:58 > 0:44:02But what made it so interesting is the fact that it plays itself.
0:44:09 > 0:44:16You see, every player piano has this kind of scrolling punch card inside
0:44:16 > 0:44:22of it where these holes correspond to one of the 88 keys on the piano.
0:44:22 > 0:44:25And as the paper scrolls along, the piano hops from note to note,
0:44:25 > 0:44:28based on the information encoded in the paper.
0:44:30 > 0:44:34Antheil had already toyed with player units in his experimental
0:44:34 > 0:44:40music, making multiple pianos play exactly in sync.
0:44:40 > 0:44:43His crazy idea is to use the same technique for
0:44:43 > 0:44:46Lamarr's remote control torpedo.
0:44:51 > 0:44:56Just as his pianos hopped between a keyboard's 88 notes to play
0:44:56 > 0:45:01a tune, the transmitter aeroplane and the receiver torpedo
0:45:01 > 0:45:04are programmed to make split-second synchronised hops
0:45:04 > 0:45:07between 88 different radio frequencies.
0:45:12 > 0:45:16It was a truly revolutionary idea, the enemy couldn't possibly
0:45:16 > 0:45:18intercept a transmitted message being
0:45:18 > 0:45:22spread across the frequency spectrum, which meant that no-one
0:45:22 > 0:45:26could stop a remote control torpedo from hitting its target.
0:45:26 > 0:45:30It's the first ever means of secure radio communications.
0:45:37 > 0:45:40It sounded too good to be true,
0:45:40 > 0:45:43and unfortunately that's exactly what the US Navy thought.
0:45:45 > 0:45:48Lamarr and Antheil succeeded in getting a patent for their
0:45:48 > 0:45:53invention, but it's dismissed by the military and never pursued.
0:45:54 > 0:45:59But despite the fact Lamarr's guided missile scheme would never
0:45:59 > 0:46:03see the light of day, the core idea behind it was destined
0:46:03 > 0:46:07to have a major impact on how we live today.
0:46:09 > 0:46:12Prompted by the prospect of all-out nuclear war
0:46:12 > 0:46:14during the Cuban Missile Crisis,
0:46:14 > 0:46:18the military dusts off Lamarr's proposal and develops it, not for
0:46:18 > 0:46:24remote-controlling a torpedo, but to secure communications between ships.
0:46:26 > 0:46:30It works, and it signals the start of a technological revolution.
0:46:31 > 0:46:35By the 1980s, the technology is declassified,
0:46:35 > 0:46:40forming the backbone to a new era in secure, wireless communication.
0:46:41 > 0:46:47Enabling cellphone users to share frequencies and talk in private.
0:46:50 > 0:46:55So, today, any time you make a cellphone call or send a text,
0:46:55 > 0:47:00or an e-mail via Wi-Fi, it's partly thanks to an ingenious
0:47:00 > 0:47:05idea from a Hollywood actress that helped launch a digital revolution.
0:47:09 > 0:47:12From our earliest experiments with recording
0:47:12 > 0:47:16and broadcasting human voices, the journey of sound has been
0:47:16 > 0:47:21all about extending the range of our voices and ears.
0:47:23 > 0:47:27But the most surprising twist of all would come nearly
0:47:27 > 0:47:31a century ago, when we first began to realise that
0:47:31 > 0:47:35sound could be harnessed for something else - to help us see.
0:47:41 > 0:47:45It's 1912 and the world reacts in horror to the news that
0:47:45 > 0:47:49the RMS Titanic had struck an iceberg and sunk,
0:47:49 > 0:47:53taking over 1,500 people with it to a watery grave.
0:47:57 > 0:48:01It's one of the deadliest peacetime maritime disasters in history.
0:48:04 > 0:48:05Like millions of others,
0:48:05 > 0:48:11the Canadian Reginald Fessenden is devastated by the loss of life.
0:48:11 > 0:48:15But he's also an inventor, and obsessed with sound technology.
0:48:16 > 0:48:21He resolves to try and prevent such a tragedy ever happening again,
0:48:21 > 0:48:23using his knowledge of sound.
0:48:26 > 0:48:30Fessenden already knows that sound travels very effectively
0:48:30 > 0:48:34through water, so he's got this idea for a maritime technology
0:48:34 > 0:48:37that could be used to detect icebergs.
0:48:37 > 0:48:42And strangely enough, it's the exact same approach that evolution
0:48:42 > 0:48:45came up with for a completely different species.
0:48:47 > 0:48:51To understand how Fessenden's idea would work,
0:48:51 > 0:48:54I've come to a dolphin aquarium in Northern California.
0:48:54 > 0:48:59OK, I'm out here in the middle of the aquarium but you guys
0:48:59 > 0:49:01aren't going to prank me and let the great white out are you?
0:49:01 > 0:49:05- Cos that wouldn't be very... - Not today.- Not today, OK, good.
0:49:05 > 0:49:08'Trainer Holley Muraco knows all about how dolphins use
0:49:08 > 0:49:11'echolocation to navigate.'
0:49:11 > 0:49:16Listen for a sound that's sort of like a zipper or a squeaky door.
0:49:16 > 0:49:18- And that will be the sound...- That will be the sound of echolocation.
0:49:18 > 0:49:21- So they're sending out a sound wave through the water.- Yes.
0:49:21 > 0:49:23- And it's going to bounce off of me.- Yes.
0:49:23 > 0:49:25And then it's going to bounce back to their ear
0:49:25 > 0:49:27and their brain will process that spatially.
0:49:27 > 0:49:32- So they'll get a sense of weird guy in the pool over there.- Exactly.
0:49:32 > 0:49:33Release the dolphins!
0:49:40 > 0:49:42OK, listen now.
0:49:44 > 0:49:46DOLPHINS CLICK AND SQUEAK
0:49:46 > 0:49:47There's some echolocation.
0:49:47 > 0:49:49Yeah, I heard that sound.
0:49:54 > 0:49:57- I can totally hear it.- Cool, huh? - Yeah, that was amazing.
0:49:57 > 0:50:00There's nothing quite like it, it's hard to describe.
0:50:00 > 0:50:02They have something we totally don't have.
0:50:05 > 0:50:07Hello, a little wave?
0:50:07 > 0:50:11Fessenden had no idea that dolphins can use sound echoes to
0:50:11 > 0:50:15visualise both the size and distance of an object underwater.
0:50:15 > 0:50:18This wouldn't be established until the 1950s.
0:50:19 > 0:50:25Oh, he's hugging you now. You're getting a dolphin hug.
0:50:25 > 0:50:27Humans have been interested in echoes
0:50:27 > 0:50:30since they were chanting in caves tens of thousands of years ago.
0:50:32 > 0:50:35But they'd never used echoes for complex navigation
0:50:35 > 0:50:39and discovery the way dolphins naturally do.
0:50:39 > 0:50:42But Reginald Fessenden is about to change all that.
0:50:44 > 0:50:47Now, it might not look as aesthetically
0:50:47 > 0:50:51pleasing as a dolphin, but this is what Fessenden cooks up.
0:50:52 > 0:50:55It looks more like a giant metal detector.
0:50:55 > 0:50:59An echo-ranging device he calls the Fessenden Oscillator
0:50:59 > 0:51:04that can use sound to see objects in the water exactly as dolphins do.
0:51:09 > 0:51:13The Oscillator was a brilliant idea. Well, actually, it was two
0:51:13 > 0:51:15brilliant ideas.
0:51:15 > 0:51:18It can generate a pulse which travels through water
0:51:18 > 0:51:21and then returns if it encounters an object,
0:51:21 > 0:51:25detecting icebergs up to 3km away.
0:51:28 > 0:51:32But, it's also a receiver converting in-coming vibrations
0:51:32 > 0:51:38into sound - making it an underwater telegraph for communication.
0:51:44 > 0:51:47It's a huge breakthrough and Fessenden is convinced it
0:51:47 > 0:51:51will save countless lives, not just through detecting icebergs,
0:51:51 > 0:51:55but also, with the outbreak of World War I,
0:51:55 > 0:52:00by detecting German U-boats in the new reality of submarine warfare.
0:52:02 > 0:52:06Unseen submarines are launching devastating attacks
0:52:06 > 0:52:11on merchant vessels, threatening to cut off Britain's food supplies.
0:52:11 > 0:52:15Fessenden's convinced his idea can contribute to the war effort.
0:52:18 > 0:52:22You see, Fessenden is a Canadian and a subject of the British Empire,
0:52:22 > 0:52:26and he's convinced his technology can help the Royal Navy.
0:52:26 > 0:52:29Unfortunately, the American company that funds
0:52:29 > 0:52:32and therefore owns his research doesn't share the same
0:52:32 > 0:52:35allegiance to the Union Jack.
0:52:35 > 0:52:39What they see in Fessenden's invention is a risky proposition.
0:52:42 > 0:52:46But faced with the financial risk of developing two revolutionary
0:52:46 > 0:52:49new technologies, the company decides to build
0:52:49 > 0:52:53and market the Oscillator as a listening device only.
0:52:56 > 0:53:01Beside himself with rage, Fessenden travels on his own dime all
0:53:01 > 0:53:05the way to Portsmouth, England, to meet directly with the Royal Navy.
0:53:05 > 0:53:11But there too, the top brass are dubious of this miracle invention.
0:53:11 > 0:53:12Fessenden later wrote,
0:53:12 > 0:53:16"I pleaded with them to just let us open the box and show them
0:53:16 > 0:53:20"what the apparatus was like." But his pleading goes nowhere.
0:53:23 > 0:53:26It was another decade before Fessenden's echolocation
0:53:26 > 0:53:28invention was finally taken seriously.
0:53:31 > 0:53:35It transforms maritime safety for ships navigating in waters
0:53:35 > 0:53:37with treacherous ice floes.
0:53:40 > 0:53:44By World War II, thousands of ships are equipped with sonar.
0:53:46 > 0:53:50And it will quickly become a fixture of every vessel in every sea.
0:53:52 > 0:53:56But soon, echo ranging doesn't just allow ships to see hazards,
0:53:56 > 0:54:00it lets fishermen spot their catch.
0:54:00 > 0:54:02It allows scientists to explore the last great
0:54:02 > 0:54:06mysteries of our oceans, revealing hidden landscapes,
0:54:06 > 0:54:11and resources, helping seismologists chart earthquake fault lines.
0:54:14 > 0:54:18Sonar was even one of the technologies used to search for
0:54:18 > 0:54:22the Titanic three-and-a-half kilometres below the surface,
0:54:22 > 0:54:2473 years after it sank.
0:54:24 > 0:54:28But Fessenden's innovation has had the most transformative
0:54:28 > 0:54:30effect on our health.
0:54:35 > 0:54:41Today, ultrasound technology allows babies and their mothers to survive
0:54:41 > 0:54:45complications that would have been fatal just a few decades ago.
0:54:45 > 0:54:48And we've actually kind of come full circle,
0:54:48 > 0:54:52we're now using ultrasound on pregnant dolphins.
0:54:56 > 0:54:58- So that's the... - That's the heartbeat.
0:54:58 > 0:55:00That's the heartbeat of the baby dolphin.
0:55:02 > 0:55:03Do we know if it's a girl or a boy?
0:55:03 > 0:55:06- I think I've seen maybe some boy parts.- Oh, really.
0:55:06 > 0:55:08So we're sort of thinking it's a boy.
0:55:08 > 0:55:10She's not showing much. Looking good.
0:55:10 > 0:55:13She looks really good. Being streamlined helps a lot.
0:55:13 > 0:55:16So we're just bouncing our sound waves using our advanced
0:55:16 > 0:55:22technology here. Somewhere in the dolphin womb there is a tiny
0:55:22 > 0:55:25baby dolphin who may or may not be hearing our sound waves.
0:55:25 > 0:55:28Kind of like, "What is that noise?
0:55:28 > 0:55:30- "Why are people talking to me?" - Exactly.
0:55:30 > 0:55:32That is really cool.
0:55:40 > 0:55:43I remember my wife and I found out that our first child was
0:55:43 > 0:55:45going to be a boy using an ultrasound.
0:55:45 > 0:55:47If you think about it,
0:55:47 > 0:55:50it's really incredible. I mean, this just about as important a piece
0:55:50 > 0:55:52of information as you're ever going to receive in your life,
0:55:52 > 0:55:54the sex of your unborn child.
0:55:54 > 0:55:58And it comes to us by sending sound waves through
0:55:58 > 0:56:02and listening to echoes off of the bones and tissue of our bodies.
0:56:06 > 0:56:12In the 150 years since Edouard-Leon Scott first recorded his voice, the
0:56:12 > 0:56:17journey of sound has been all about discovering ever more inventive
0:56:17 > 0:56:22ways of sending it - be it over the airwaves or right inside our bodies.
0:56:25 > 0:56:28You could argue that the most transformative part of that
0:56:28 > 0:56:34journey was where it began - capturing the sound of our voices,
0:56:34 > 0:56:37in song, and in conversation.
0:56:37 > 0:56:39Sound recording gives us
0:56:39 > 0:56:43the ability to revisit the most cherished memories in our lives.
0:56:43 > 0:56:47I mean, I know I can't separate out my memories of adolescence
0:56:47 > 0:56:50from the music that I listened to as a teenager.
0:56:50 > 0:56:53And today, hearing one of those tracks can send me
0:56:53 > 0:56:56back to the past in a heartbeat.
0:56:56 > 0:57:00Sound recording becomes a part of who we are.
0:57:04 > 0:57:08And that's why it's fitting, really, when we packed up the Voyager
0:57:08 > 0:57:13spacecraft in 1977 to send into uncharted space
0:57:13 > 0:57:17as a gift to unknown civilisations, one of the main objects we included
0:57:17 > 0:57:22to represent all of humanity was a gold-plated phonograph disc.
0:57:23 > 0:57:27Recorded on it were greetings in 55 different languages.
0:57:32 > 0:57:33Just last year,
0:57:33 > 0:57:38NASA announced that Voyager One had left the solar system.
0:57:38 > 0:57:41It will be roughly 40,000 years before it encounters another
0:57:41 > 0:57:43planetary system.
0:57:43 > 0:57:45But when it does,
0:57:45 > 0:57:50it will be carrying the sound of the human voice saying, "Hello."