Experiments with parametric and directional speaker systems have been going on since the early 1960s. Ultrasonic sound has much smaller wavelengths than regular audible sound making it much more directional than a traditional loudspeaker system.
Most speakers are designed to throw sound as far and loud as possible. Parametric speakers are more like a laser beam with the sound focused at high intensity into a relatively small area. The result is that two people can be standing only a few feet apart from each other yet only one of them will hear the directional audio waves emanating from the parametric audio source.
Parametric Speakers Have Many Uses
The affects of parametric speakers are not only a great demonstration of how sound propagates through air but also offer many useful applications. Some of the possible uses for this amazing technology are:
In areas with large groups of people such as subways, airports and other public places, it may be beneficial to have a message playing at escalator landings, door entrances and other places where only the people in that small area need to hear the announcement.
Parametric speakers like the Soundlazer have already been used in commercial advertising. A person standing under a billboard to large video screen is the only one able to hear a recorded message. The advantages to this are twofold. The ultrasonic waves, being focused will get the attention of the listener and the repeated message will not be heard by others. Patrons and store clerks that would normally be distracted by the same message repeating over and over on a daily basis will no longer be annoyed by advertising that uses parametric technology.
Security / Alarm Systems
Parametric speakers combined with high decibel sirens have been used to deter robberies and other criminal activities.
There are rumors surfacing on the web that some political candidates have used parametric arrays to beam live information directly into the ears of public speakers so that no earpiece or TelePrompTer is needed. While this hasn’t been confirmed, it does offer interesting possibilities.
The Soundlazer Project
THIS IS ADVANCED TECHNOLOGY!
This website and products are the result of experimentation with ultrasonic carrier waves to transmit audio in a directed beam of sound. A few companies around the world have had mixed results with this technology. The goal here has been to build a low cost, open source, parametric array so that experimenters and hobbyist can help take this technology to the next level.
Doing a quick Google search for “parametric speakers” or directional sound will return a small number of results and little information on exactly how this fascinating technology works. The websites for the few commercially available products do not explain the science or drawbacks such as limited bandwidth in the audio signal, exponential signal drop off through air and the many other factors that make this audio phenomenon difficult to master.
There have been a couple of “homebrew” projects coming out of Japan and other parts of the world with questionable results. Limitations in time, money and expertise in the field of ultrasonics and parametric speaker design have slowed the advances in this field until now.
Introducing the Soundlazer
-the first open source, hackable parametric speaker with integrated DSP (digital signal processor) that offers the best sounding directional audio.
Directional sound that you control
-An on board signal processor conditions the audio from your iPhone, iPod, iPad, computer or any other source. The sound can only be heard by someone standing in the Soundlazer’s path. Like a laser, the parametric array sends the audio signal over a ultrasonic beam which can also be bounced off of walls, statues or any other hard object to make the sound appear to be coming from another direction.
Open Source and Customizable
-All design files and programming instructions are included with each Soundlazer. Those who wish to dig into the inner workings of the device can purchase the Sigma Studio USB programmer and software from Digikey and create their own custom waveforms to improve the sound or expand the Soundlazer to unlimited possibilities.
The Soundlazer startered on Kickstarter Kickstarter
Because of all the technology and quality of the enclosure, building the first run of this product was going to be a bit pricey. Crowdfunding seemed like the best route to go. With group buying power, I was able to build the Soundlazer in a large enough quantity at a price we all can afford.
Here is the original Kickstarter page