A focused speaker is a device that generates mid to high-frequency audio in a narrow beam of soundwaves. Unlike low-frequency soundwaves, mid to high-frequency sound can be focused almost like a laser beam. These waves travel at long distances but are loudest at the center. They are only heard by those standing in front of the speaker. Directional or focused speakers are very different from traditional speakers in the way they distribute sound. While the role of conventional speakers is to transmit the audio as widely and as loudly as possible, directional speakers aim to focus the audio into a concentrated area allowing for much better sound clarity, usually at lower decibel levels. Directional speakers are commonly used to address specific areas within a crowd rather than disturbing a wider audience.
As mentioned, directional speakers can transmit clear information over much longer distances at lower power. That is because the audio doesn’t fan out from the source like traditional speakers, but instead remains concentrated in a tight beam. The directivity of focused speakers is significantly better than with regular speakers, which helps eliminate echos and other interference that usually degrades audio quality. Focused speaker technology like the Soundlazer is still very much in development with new designs and uses appearing every day.
What is a Focused Speaker?
Today, focused speakers generate an ever-increasing interest among audio enthusiasts and the general public, but that wasn’t always the case. Focused speakers are a relatively new concept, and the first experiments with its technology only started in the 1960s. Although back then, the idea of focused speakers was still in its infancy; today, with innovations in technology like Soundlazer, it is becoming more prevalent in our daily lives.
Directional speakers are a fantastic way of putting sound where it is needed while eliminating it from surrounding areas. There are a variety of focused speakers on the market from personal units to military size devices. They mainly differ in size, power output, and price. LRADs are the largest and most expensive focused speakers that can transmit directional sound over very long distances to crowds. Soundlazers, on the other hand, are tiny, low-cost directional speakers that are useful for directing audio at a handful of listeners. The beauty of both these systems is that the sound will only be loudest to the people within the centers of the audio beam. The possibilities are endless and only limited by your imagination and budget.
Here, we will analyze how focused speakers work in more detail. Focused speakers use specialized technology for transmitting sound. It has taken many companies years of development to make this type of device possible. Soundlazer, as an example, was the first open-sourced parametric speaker system that is fully hackable, allowing programmers and sound enthusiasts to help advance this field further. Soundlazer is a type of parametric speaker that allows for easy integration with iPhones, iPads, computers, and any other source. It also has an on-board digital signal processor (DSP) specifically designed to produce the best possible audio quality for this type of directional speaker system. Years of development and contributions from the tech community have vastly helped improve this technology.
How Does a Focused Speaker Work?
Unlike the traditional loudspeakers, where the goal is to project sound in a wide as area possible, directional speakers do the complete opposite. Focused speakers emit mid to high-frequency sounds in a directional beam. The audio’s shorter wavelengths help keep the soundwaves together. By using multiple smaller transducer or speakers elements in a parametric array, soundwaves emitting from the speaker remain in parallel waves instead of dispersing in all directions. When a person stands within the beam, they will hear the loudest audio, while a person standing just a few feet away hear a much lower volume of sound.
If we dive a bit deeper into the technology itself, we will learn that focused speakers utilize multiple small sound transducers that emit parallel high-frequency waves. These transducers are usually visible as the little circles on the speakers. Numerous pressure waves of high-frequency sound emanate in a straight pattern from the surface of the array. Parametric speakers may produce sound in the ultrasonic or audible range depending on their design. In normal conditions, ultrasonic audio is inaudible to the human ear, which is why people around the speaker can’t hear it. But once someone interferes with the parallel waves (if we step into the sound beam), these waves will collide, interfere, or combine to create audio at lower frequencies that can be detected by the human ear. This phenomenon will make the sound audible for the person standing within the beam of the directional speaker.
The process of these parallel waves combining and mixing is called parametric interaction. Directional sound is created by piezoelectric transducers that transmit what is known as a carrier wave. To be more precise, these piezoelectric transducers transmit a beam of ultrasonic audio at a frequency of around 40kHz (40,000Hz), which is undetectable to the human ear. The sound beam is modulated with the audible information from a source such as an MP3 or mobile phone. Interestingly, piezo transducers used in ultrasonic parametric speakers are similar to the ones used in parking warning systems in most modern cars.
The result is a focused speaker that will emit a directional sound similar to a laser beam. Only those standing inside the path of the soundwaves will be able to hear the audio, while other people on the outside will hear a little sound. That is because of the short wavelengths, higher frequencies that are much more directional than low ones.
Focused speakers are also sometimes called parametric speakers due to the parametric interaction of the individual sound waves. Even though there are many types of directional speakers, they all use a form of this technology. Sometimes, they are different in size and the range that they can cover, while other times, they differ in the way they operate.
What are the uses of directional speakers?
Although directional speaker technology is still in its infancy, people are finding exciting new ways to use these fantastic devices. At this moment in time, directional speakers can be found in public spaces or for personal use. It just depends on the user’s needs.
Public Safety and Public Addressing
One of the more popular uses of directional sound speakers is for public safety. Large and expensive units like LRAD direct and deter people during public gatherings and demonstrations. There has been some controversy over the use of these types of directional speakers. These concerns are outweighed by the fact that they ensure public safety without causing any real danger to the people within a crowd.
Additionally, focused speakers are suitable for public addressing where only a specific group of people need to hear the message. That can be beneficial in various civil riots or gatherings. Although traditional speakers are more common for addressing the public, they can be hard to understand in noisy environments. Directional speakers deliver a much more intelligible audio message while breaking through the background noise. The sound from LRAD is intense and can get pretty annoying, so the message is not only clear but also memorable. Warning tones can also be transmitted from the LRAD that most people have a hard time enduring for any length of time. These tones are an effective way of scattering or moving people away from particular areas of concern, which helps to improve public safety.
In Museums or Exhibitions
One of the best things about directional speakers is that they transmit the sound in such a way that only a few people can hear the audio. This feature is perfect for museums and galleries where there can be a large number of displays with people wandering. Focused speakers are ideal for directing important information to only the people interested in allowing them to learn valuable information without distracting from or interfering with other presentations.
Have you ever been to a museum where they use conventional speakers for presentations? You were able to hear the information clearly, but the many sounds that came from other loudspeakers diminished the experience.
Organizations can offer visitors a unique experience by incorporating focused speakers like Soundlazer into exhibits. It is a perfect opportunity to bring unparalleled technology to your environment while improving the knowledge and experience of the audience.
Focused speakers also provide a completely different experience that can differentiate one museum from another. Visitors will be more likely to remember the exhibitions and will want to come back or recommend it to others. This type of technology is undoubtedly revolutionary when it comes to improving all types of media presentations.
For Commercial Advertising
By utilizing focused speakers in multimedia advertisements, you can attract attention and interest in your products. We are not only talking about TV ads here because, directional sound, draws an audience in by surprising them with sound. Directional speakers can also present a much clearer message to a defined group of people standing right in front of a display.
Another example of using focused speakers for advertising is in various shops, where there is a need to promote individual products. Directional sound is an effective way to address only the people standing next to the product or to grab their attention. By directing sound to the individuals, it also helps make a lasting impression for a brand. Directional speakers are clearly an effective tool for advertisers to get their message out to their customers.
For Security Purposes
Imagine a robber trying to break into your house in the middle of the night when suddenly, a loud sound starts coming from a speaker above. By focusing an intense beam of sound, you could cause the b .urglar to flee the scene. A consumer version of an LRAD, although not yet available, would be the perfect focused speaker for this task. While LRADs are useful for crowd control, consumer applications like this have are still in development.
Directional speakers would make a great addition in the field of home security and can assume a position over doors or entrances where robbers might enter. There is a higher chance of safety when combining focused speakers with lights, sirens, and other security devices.
Other uses of focused sound
As directional speakers offer integration with other devices, they can be a very effective way of putting the sound where it is required. For example, focused speakers can be perfect for those who want to listen to podcasts or radio in public, but at the same time, they don’t want to disturb other people in the same area.
Another excellent example of how focused speakers can work with other devices is televisions. Imagine being in a hospital where there are usually televisions for every single bed. The sound from TVs can be quite loud, and for patients, hard to hear. This is an example where focused speakers could come in handy. They can be useful for transmitting the sound from the television or radio directly to the patient, while other people won’t be able to hear a thing. Focused speaker systems also eliminate the discomfort caused by headphones or earpieces,
Directional sound is a compelling way to lower noise pollution and direct the sound towards individuals. They also improve the comfort level for the listener by not attaching them to a listening device.
As Non-Lethal Weapons and for Self-Defense
One of the more important uses of directional speakers is for self-defense and non-lethal weapons. These very high power, directional speakers use soundwaves that can immobilize people without any long term effect. Focused speakers are more and more prevalent with law enforcement units to deter individuals or groups of people from creating havoc. There are high frequency, ultrasound, and infrasound acoustic weapons in use today. Each of these devices has limitations, and the effectiveness is still under debate.
Some of the physical consequences of such weapons include dizziness, inability to hear, nausea, instability, and overall immobilization. In severe cases, the higher power systems can cause partial or complete deafness and damage to tissue along with internal organs. More and more law enforcement agencies use the power of directional sound in one form or another to deter criminals and increase public safety. However, the long term effects are still under investigation.
The list of applications is almost endless, and these were just a few concrete examples. Directional speakers can be useful anywhere where eliminating excess sound while delivering a clear message is vital. The great thing is that this technology is continuously advancing and improving, which will lead to even more choices in directional speaker products in the future.
Different Types of Focused Speakers
There are many subtypes of focused speakers that can be useful in different ways. They can vary in their design, the role that they play in their environment, power, loudness, the size, or the way they transmit sound. The basic idea is still there: they use some kind of transducers to transmit high-frequency sounds in a narrow beam.
Overhead focused speakers mount on ceilings or overhead structures. Their purpose is to project sound downwards similar to the way water flows in a shower. These speakers offer a charming private listening space but also are a bit confining. Their large domes can be distracting or take away from the decor of the room. Some people have compared these types of directional speakers to the cone of silence from the classic TV show, Get Smart. They might hang from ceilings over tables or even pieces of art where a specific message plays. They do have an advantage in that the dome shapes of these speakers can help block ambient noises from the listener and offer a more private feel during the presentation.
Another type of focused speaker look more like conventional speakers and connect to audio devices like computers, phones, or televisions. These are popular for personal use but often seen in retail stores, airports, train stations, and other public places. The role of these speakers is to transmit the sound in a particular direction where people most often congregate. The speakers can broadcast travel information, visitor guides, advertisements, and any other useful facts. As an example, arriving flight information for a specific plane can be projected via a directional speaker at each gate without confusing other passengers. In an electronic store, where many televisions are on display, directional speakers could be used to point out the features of a particular model of TV. Focused speakers can be connected to the device to play the sound from the tv to avoid noise pollution in the store.
Since the introduction of Soundlazer a few years back, there have been many copies showing up on the market. Unfortunately for people who only look at the price, they soon discover that the circuits in these devices lack any complex signal processing. A digital signal processor (DSP) is one of the most critical components in any type of beamforming or parametric device, especially focused speakers. The DSP is crucial when attempting to deliver high-quality audio with any kind of directional speaker.
Soundlazer is a parametric speaker that allows the users full control over the sound. These parametric speakers are very different from traditional speakers. The goal of the regular speakers is to transmit the audio in a cone-like fashion. That is important when needing to address as many people as possible. Parametric speakers like the Soundlazer use high-frequency pressure waves to produce a narrow beam of sound that is like a laser. This feature gives the Soundlazer the edge over the traditional speakers when it comes to directing audio to specific places within an area.
Soundlazer has the advantage over other focused speakers as it is the first parametric speaker to be open source. It is thus fully hackable, allowing sound enthusiasts and experts to modify it in their way and learn more about this incredible technology. Soundlazer also allows easy integration with audio players like the iPhone and other mobile devices. Any line or headphone level audio source can connect through the standard 3.5mm audio jack.
Another useful feature of the Soundlazer is also that you can completely control the sound that it emits. You can control the direction or bounce it off of walls or other hard objects to make the sound appear like it is coming from another source.
Soundlazer offers the highest level of quality for various uses. It is perfect for personal or commercial use. Some good examples of where the Soundlazer can be useful are in public places and commercial advertising, as we have already discussed. The choices are almost endless. The user’s imagination only limits the possibilities.
Focused speakers are becoming more and more prevalent, and the general public is only now gaining awareness of the technology. While they are still very much in their infancy, the possibilities for focused speakers are almost endless. It is our goal at Soundlazer to continue to make significant advances in the world of focused sound.