What do you think of this: Holosonics

[Veracohr]

I'd like to know what people's thoughts are on this. To me, with minimal acoustic knowledge, it doesn't make sense. I don't see how it could be. From http://www.hollywoodreporter.com : [quote]Sound - For Your Ears Only 24/07/2003 09:36 AM Chris Marlowe LOS ANGELES (Hollywood Reporter) - Throughout history, there have been people who heard voices inaudible to anyone else. Joan of Arc, Galileo and some schizophrenics, for example. But imagine how useful it would be if a director could speak out loud and have just one specific actor hear the instruction. Or take another scenario, one of a family on a five-hour drive to a relative's house. The parents want to hear their Eric Clapton CD, while the kids in the back want to watch their Bob the Builder DVD for the umpteenth time. Picture a vehicle in which each faction can hear their choice of audio, without the other's preference bleeding through. Nobody needs headphones, either, so everyone can still talk to one another. This is not the stuff of science fiction. In a potentially revolutionary development, at least two separate and very different companies have already turned the concept of directed sound into reality. Speakers work basically by physically creating waves in the air, using a membrane or other mechanism to pump the vibrations out, which means they disperse in an ever-wider arc. In contrast, Holosonic Research Labs Inc. and American Technology Corp. disrupt the air with ultrasonic waves at about 100,000 hertz, a frequency not even dogs can hear. This enables the companies to transmit a highly focused sound somewhat like how a flashlight beams a focused light. A person can speak in a normal voice and be heard privately up to 600 yards away - yet anyone more than a couple of feet to either side of the intended listener won't hear a thing. Additionally, the targeted beams can reflect off a hard surface, making it seem as though the sound is actually emanating from that surface. American Technology gets most of the publicity, primarily because of its colorful chief inventor - the largely self-educated Elwood "Woody" Norris, who is obsessed with getting his personal minihelicopter idea off the ground and seems to enjoy being labeled eccentric. The Southern California-based company calls its system HyperSonic Sound Technology, and one of its first customers was the military: the guided missile destroyer USS Winston S. Churchill had an HSS system installed for sea trials of its usefulness in communications, perhaps as a substitute for the isolation of headphones. According to Robert Putnam, American Technology's vp investor relations, other experiments are under way to see how effective HSS could be in creating decoy sounds and noise harassment assaults like the one used against former dictator Manuel Noriega in Panama. Despite the relative lack of media attention, however, there is a serious competitor to HSS. Working just outside of Boston, and while still a student at MIT, F. Joseph Pompei devised what he called Audio Spotlight and founded a company called Holosonics. He delights in telling how he tested his invention in the college's media lab atrium - he tricked caterers into thinking they had dropped a glass by reflecting the appropriate sound effect off the floor directly behind them. They spun around to see the damage, completely unaware of Pompei aiming his device from five floors up. Making the technology commercially available, Holosonics whispered the word "Invensys" in the ear of randomly selected diners at that company's corporate dinner, with no discernible source. It enlivened a showcase for AOL Time Warner by sending voices and sound effects flying around overhead. Neither inventor had entertainment in mind initially, but it didn't take long to realize that there are many such applications. Just think of how many times a production has jolted to a dead stop because a star forgot the next line. Wouldn't it be amazing if a private voice could provide the needed cue? There would be no wires, no spoiled soundtrack and nobody besides the talent and the prompter aware of the narrowly averted retake. A coordinator could speak with a stunt person working in a dangerous environment hundreds of feet away, yet not risk startling anyone else in the area. A stage manager could use it to scare birds away from an outdoor set without annoying the humans. On a more personal level, a night owl could watch TV in bed without the sound disturbing their sleeping partner. Record and DVD stores could have audio beaming down so that only those customers directly in front of the specific product's display could hear it. Kiosks, ATMs, vending machines, museum exhibits, theme park motion rides and other applications are being created all the time. In short, Minority Report might not be all that far in the future. Noise pollution could be reduced, too. "If you were to put regular speakers in a retail establishment, it would sound like a video game arcade," Putnam said. "Or a neighborhood annoyed by a nearby fast-food service window could ask that the speakers be replaced by targeted beams of sound." Looking at entertainment-specific applications, American Technology is working with RCA Thomson, Dolby Laboratories and Harman International on ways this new kind of speaker could be useful in home theaters. Putnam said HSS Technology speakers could be built right into the video screen - today's surround sound speakers could be replaced with "virtual speakers" created by directed sound beams, no boxes or wires needed. The sound would be synchronized so the listener would perceive the sound as coming from the back, the side or wherever else was appropriate. Dolby is also exploring the potential of HSS for cinema sound and professional surround sound systems, though that is at a preliminary stage. "In a theater setting, the sound would scan across the screen," Putnam said. "The actual sound could come from the actual screen - it would come from the actor's mouth. You could also use it to spray sound from behind and move forward." American Technology is developing what it calls a personal bullhorn, too. "You could use it to direct actors, pinpointing them without blaring it to everyone," Putnam said. "Cues, directions, special effects in auditoriums, instructions to extras, whatever needs to be said that doesn't need everyone to hear it." Holosonics made its first foray into the commercial world when it fitted out a concept vehicle for DaimlerChrysler. Each of the seating positions had a flat disk embedded in the roof lining, enabling the passengers to sit in their own sonic zones. Pompei's first auto demonstration was nerve-racking, he said. "The driver was listening to Nena's '99 Luftballoons,' and the passenger was listening to heavy metal," he said. "Nobody was saying much. I was really nervous until one guy turned to the other and asked, 'Is your side on?' It worked so well that they couldn't tell both sides were turned up." Since then, he has been approached by General Motors, Toyota and Ford. Holosonic's first public installation was unveiled almost three years ago at Sega Theme Park in Tokyo and can still be experienced. Audio Spotlight projects the music from a painted wall, and guests try to figure out where it's coming from before special lights come on and solve the mystery. Both companies are building on earlier work by scientists including professor David Blackstock and his colleague Mary Beth Bennet at the University of Texas in the 1970s and by Masahide Yoneyama and his team at Ricoh in the 1980s. Pompei in particular was influenced by the work of Peter J. Westervelt and Orhan Berktay. But these predecessors could not achieve a practical degree of fidelity and range. In fact, American Technology said its products are not yet really perfected for broadcasting music. Pompei, on the other hand, said his background as a musician made it essential that he achieve that goal before he put Audio Spotlight into production. Other musicians have responded to his concepts. "U2 kept coming by the lab, and eventually we went out to L.A. and took measurements to see what it would take to get the Edge's guitar sound to fly around," Pompei recalled. "We're working on that design now, but they're delighted with the prospects." Pompei is also working with the Children's Museum in Boston to design an interactive music presentation that doesn't interfere with other exhibits. That evolved from a project Pompei created with his MIT professor Barry Berkow. Displayed in Dublin, Ireland, and Adelaide, Australia, that installation piece let viewers choose which soloist they wished to see and hear perform with a jazz quartet. The Bibliotech Nationale in France and golf's PGA European Tour, each of which requires a quiet atmosphere, already have Audio Spotlights installed. So does the Australian Center for the Moving Image. "It bought a bunch of them to augment the movie experience, so you can get effects like bullets flying behind your head," Pompei said. "Alternatively, the sound can actually come from a specific place on the movie screen - directly from the actor's mouth, if you want." Both American Technologies and Holosonics believe that the future will surprise them with applications for directed sound. "The more we expose this technology, other people will come up with ways to use it that we never thought of," Putnam said. "We're creating a market that doesn't exist today."[/quote]And from http://www.holosonics.com : [quote]The directivity (narrowness) of any wave producing source depends on the size of the source, compared to the wavelengths it generates. Audible sound has wavelengths ranging from a few inches to several feet, and because these wavelengths are comparable to the size of most loudspeakers, sound generally propagates omnidirectionally. Only by creating a sound source much larger than the wavelengths it's producing can a narrow beam be created. Clearly, having loudspeakers twenty metres wide is not very useful. therefore ... to make a narrow beam of sound from a small acoustic source, we instead generate only ultrasound. The ultrasound, whose wavelengths are only a few millimetres long, are much smaller than the source, and consequently travel in an extremely narrow beam. Of course, the ultrasound, which contains frequencies far outside our range of hearing, is completely inaudible. But as the ultrasonic beam travels through the air, the inherent properties of the air causes the ultrasound to distort (change shape) in a predictable way. This distortion gives rise to frequency components in the audible bandwidth, which can be accurately predicted, and therefore precisely controlled. By generating the correct ultrasonic signal, we can create, within the air itself, essentially any sound desired. Note that the source of sound is not the physical device you see, but the invisible beam of ultrasound, which can be many meters long. This new sound source, while invisible, is very large compared to the audio wavelengths it's generating. So the resulting audio is now extremely directional, just like a beam of light. Often incorrectly attributed to so-called "Tartini tones", the technique of using high-frequency waves to generate low-frequency signals was in fact pioneered by physicists and mathematicians developing techniques for underwater sonar over forty years ago. Over the past two decades, many others have attempted – and failed – to use this technique to make a practical audio source. Through a combination of careful mathematical analysis and engineering insight, the Audio Spotlight sound system has become the very first, and still the only, sound beam system which generates low-distortion, high quality sound in a reliable, professional package.[/quote]

[S_Gould]

Oh, it works, all right. I'm not going to try to get into the physics of it, though I DO understand it in a rudimentary way. But it's all old news - I'd be interested in seeing some kind of shipping product so I could hear how it actually sounds. Until that time my only thought is that it's an interesting technology with a lot of potential...depending on how it gets implimented. Scott

[Veracohr]

[quote]Originally posted by S_Gould: [b]I'd be interested in seeing some kind of shipping product so I could hear how it actually sounds. Until that time my only thought is that it's an interesting technology with a lot of potential...depending on how it gets implimented. Scott[/b][/quote]See the Holosonics website I linked, it shows some transmitters and such products.