Recent research suggests that companies are delaying the installation of digital signage for their offices and stores, or are removing their existing installed digital signage solutions based on claims of high introductory costs, and difficulty in creating engaging content for their audiences.
Those claims sounds daunting, except they aren’t accurate. Large, full HD monitors have dropped almost 40% in cost over last several years, and are more affordable than ever. These new screens are larger, cheaper and offer a much more engaging presentation than was possible even a few years ago. The WebSuite Digital Signage Platform from MagicBox allows users to layout graphics and information that are easy to create and implement, and even a novice can create a professional looking signage array in very little time.
People are becoming more and more accustomed to multimedia exposure throughout the day. From television and media players in cars, to digital menu boards in restaurants, digital signage is becoming more mainstream. Customers expect to be engaged with information and entertainment, and successful businesses are using digital signage technology to capture new customers— especially a younger demographic with a higher disposable income.
Some worry that the technology is intimidating, and that digital signage will require too much valuable time with designing and programming content. With the Aavelin and Websuite from MagicBox, you have a scalable, complete, turnkey digital signage & video messaging system for broadcast or hi-definition applications. It’s the digital signage market’s leading system for ease-of-use, allowing you to you use your own Windows PC to create prescheduled or ad-hoc multimedia content for playback on your dedicated Aavelin player. Use Aavelin Composer Software to create, schedule, and manage dynamic digital messages in the background, leaving your PC free for other work. Control a single player or multiple units from a remote location, saving time and money. WebSuite technology provides even further flexibility, allowing you to update all of your signage pieces from the cloud using a web browser, and with Android mobile devices. .
WebSuite from MagicBox has a robust and user-friendly interface that allows you to easily create high-definition graphics, text and more for your display. No need to hire a full-time designer; you can easily add eye catching graphics, directed marketing pieces, and special offers to your customers.
Sports bars are installing monitors in their restrooms, so customers never miss a game-changing moment. Restaurants are creating digital menu boards in the lobby to allow customers to view the menu and daily specials before even being seated. Department stores can now offer displays with maps to guide customers to specific areas, and also provide them with special discounts and offers that encourage additional sales. Digital signage is the future of customer engagement, and it’s time to stop asking how you can afford it, but instead, ask how you can afford to continue without it.
Visit our website at http://www.magicboxinc.com to learn more. You can also call our offices at 541-752-5654 or email us at email@example.com
Beamforming arrays date back over 100 years, and were first used in the military for determining the bearing and location of aircraft, ships, and submarines. Until the mid 1970’s, when microprocessors became widely available, these arrays were 100% acoustic and fairly primitive. Modern software development and digital signal processing techniques have substantially advanced the state of the art of this technology. With good design and engineering, it’s now possible to employ an advanced microphone array system to capture desired sounds and produce a highly intelligible, superior-quality audio signal.
Also known as spatial filtering, beamforming can be applied to both sound waves and radio energy, and thus is sometimes discussed in the context of cellular telephones, wireless networking, biomedicine, sonar, seismology, and even radio astronomy.
This paper focuses exclusively on beamforming as a method of sensing and filtering acoustic waves for enterprise video and telephone conferencing applications, and describes emerging techniques and technologies to improve the capture and processing of acoustic patterns, and the clarity of human speech in corporate conference rooms.
Acoustic Beamforming Theory
Research Scientist Andrew A. Ganse of the Applied Physics Laboratory at the University of Washington explains that “The basic point in beamforming is, when you set multiple transducers next to each other sending out signals [or listening for sound waves], you’re going to get a kind of interference pattern, just like you see in a pond when you throw several stones in at once and create interfering ripples. If you select the spacing between your transducers and the delay in the transducers’ signals just right, you can create an interference pattern that’s to your benefit, in particular one in which the majority of the signal energy all goes out in one angular direction.”
By combining elements [i.e., antennas or microphones] in a phased array, so that signals at particular angles experience constructive interference while others experience destructive interference, beamforming can be used to achieve spatial selectivity and elimination of unwanted signals.
Beamforming microphones are part of a larger family of mics considered to be high-directionality, or perhaps ultra-directional microphones, due to their stunning sound quality, advanced performance, and similarities to phased-array radar.
As all sound professionals know, an omnidirectional microphone is one that picks up sound from all directions. The disadvantage of omni mics is that they often result in a sound feed that is reverberant, or hollow, and full of ambient noise from all directions in a room. A basic directional microphone still in common use today is the cardioid mic, perfected in the early 1940’s. Cardioid mics sound less reverberant and less noisy than omni mics because they attenuate off-axis reflected audio and noise by reducing sound pickup from the sides and rear. But cardioid mics have limited selectivity or filtering capabilities, which can be surpassed using beamforming technology.
Beamforming can be used to select, or focus on, just those sounds or voices that you want conference participants to hear, while rejecting all unwanted sounds. Selecting desired sound sources and rejecting undesirable sounds has been the goal of audio engineers for most of a century. With acoustic beamforming and integrated digital signal processing made possible by modern microprocessors and software, this is now technologically possible.
Traditional directional microphones may be used in conferencing applications to perform limited spatial filtering to improve audio quality. These microphones have an acoustic pattern that selectively picks up desired sound waves in one region of space and rejects others.
Beamforming is a signal processing technique carried out by a processor using input from the beamforming microphone array. The signals from the various microphones are combined such that signals at particular angles experience constructive interference, while others experience destructive interference.
Superior spatial selectivity can be achieved using beamforming techniques so that certain regions (sound directions) can be amplified, and other regions can be significantly attenuated. Beamforming processing components can also be configured to attenuate unwanted sounds originating from the direction of a door or window into the conference room.
To adjust and tune the directionality of the array to focus on desired sounds, a beamforming array system adjusts the phase and amplitude of the sounds reaching each microphone, to create a pattern of constructive and destructive interference in the wave front. Information from different microphones is then combined such that the expected acoustic pattern is preferentially processed and fed into the conferencing audio stream.
Advanced beamforming techniques employ interference patterns to change the directionality of the array, so that information collected from the various microphones can be combined to give preference to the expected acoustic patterns. Adaptive beamforming algorithms may also be included to automatically adapt to different situations and environments.
The most advanced, state-of-the-art enterprise video and teleconferencing systems today employ professionally engineered beamforming microphone arrays and associated components and processors.
The Emergence of Beamforming for Conferencing Applications
It’s common practice in audio/video teleconferencing systems to deploy a grouping of cardioid microphones, placed on a tabletop or mounted in the ceiling. When each directional mic is properly aimed at an individual and connected to a professional conferencing mixer, excellent audio pickup can be achieved. Similar results can be accomplished with wireless lapel or hand mics.
In a boardroom environment, however, there is frequently a desire to maintain a clean, cultured, corporate image, and a collection of microphones resting on tabletops or hanging from ceilings can be visually disruptive and damaging to interior designers’ esthetic goals. Integrated three-microphone arrays offer a reduction in the number of visible microphone elements, but nonetheless have a hard technical look that may also inhibit an ultra-clean, styled appearance.
Other disadvantages of tabletop and ceiling microphone strategies include the extra work that goes into maintaining numerous microphones, checking wireless batteries and sound levels, the inconvenience of worrying about whether everyone has remembered to clip on their wireless mics, whether any noise is being introduced, and constantly optimizing mixer levels. There are also high costs associated with mics, mounts, stands, cables, installation, and upkeep.
In contrast, a modern beamforming mic array delivers the ultimate in convenience, speech intelligibility, sound quality, and reliable communications. Beamforming arrays are less visually intrusive, and when mounted strategically, can disappear unobtrusively into the background.
With an array on a conference room table or mounted on ceiling or wall, the various microphone elements in the array, along with associated steering algorithms, digital signal processing, and echo cancellation can “zoom in” acoustically on individual conference participants and deliver sound quality that is superior to traditional conference room sound-gathering methodologies.
World’s First Professional-Grade, 24-Element Beamforming Microphone Array
The convergence of modern conference room interior design with advances in acoustic technology and digital signal processing is accentuated by the recent availability of the ClearOne 24-element Beamforming Microphone Array, the first solution of its kind in the professional audio industry.
Made possible by ClearOne’s beamforming technology, digital signal processing, adaptive steering, and next-generation acoustic echo canceling processes, the 24-element Beamforming Microphone Array system is a groundbreaking, integrated teleconferencing system consisting of microphone capsules, on-board-processing, advanced software, and a connected digital electronics mixer stack.
As many as ten traditional microphones can be removed from a conference room and replaced by the sleek, attractive enclosure of the beamforming array. The on-board intelligence, spatial filtering, and signal processing capabilities of the integrated system give it twice the pick-up range of other microphones and significantly reduce height, distance, and angle constraints.
Each Beamforming Microphone Array unit operates in collaboration with a ClearOne CONVERGE® Pro conferencing system, which shares processing tasks and provides echo cancellation, noise cancellation, filtering, gating, level control, and adaptive acoustic modeling to deliver the most natural conferencing audio experience possible.
The combined beamforming and signal processing technologies automatically steer tightly-focused audio pickup beams towards people speaking, and filter out unwanted sounds and reflections to reduce room noises and eliminate those hollow reverberant sounds that commonly plague conference room environments.
Beams that would be aimed towards unwanted regions, such as windows, doors, or noise sources, can be disabled by the installer in software. Up to three beamforming arrays can be attached to each supported CONVERGE Pro system, and as many as sixteen beamforming arrays along with six required CONVERGE Pro conferencing systems can be networked together to provide coverage in multiple regions, rooms, or portions of a building.
Simplicity and Ease of Installation
The ClearOne Beamforming Microphone Array is a plug-and-play device that can be easily configured, customized and installed. Minimal configuration is required, since the technology is completely internalized. The array’s sophistication, and its associated software, processors, and electronics are so intelligently implemented, that a technician with average audio conferencing skills is capable of performing the installation and configuration.
+ The ClearOne Beamforming Microphone Array is no more complicated to install and setup than any other microphone. Integrators experienced in the installation and configuration of typical conference microphones can easily configure the array.
+ The only connections required are a single Power over Ethernet (PoE) and one audio connection to the expansion bus of the CONVERGE Pro unit. No custom cables, no wiring terminal blocks, or any other onnections are needed.
+ Although completely customizable to meet the needs of nearly every application, the ClearOne Beamforming Microphone Array default configuration works right out of the box. Unlike standard conference microphones which require experience in configuring proper gain structure between devices, the Beamforming Microphone Array is pre-configured to work directly with the internal gain structure of the CONVERGE Pro. When installed according to ClearOne guidelines, the only adjustments will be minor gain changes to customize levels for your application.
The Ultimate in Teleconferencing Sound Quality
In the world of professional audio and video teleconferencing – beamforming microphone arrays and their associated mixers, digital signal processors, and echo-canceling functions represent the newest, most advanced technological innovations, breaking new ground for teleconference sound fidelity, clarity, and intelligibility.
Modern beamforming technology has the proven ability to surpass traditional techniques for clearly capturing and reproducing human voices in conferencing applications, and rejecting unwanted sounds, to optimize collaboration and understanding among conference participants.
When conveniently installed in conference center ceilings, walls, or tabletops, beamforming microphone systems deliver the best, most unobtrusive options for the physical placement of microphones, making them the superior choice for flawless conferencing audio in any setting.
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Digital signage is on the rise and here to stay.
A new study from the global market research and consulting company MarketsandMarkets estimates that the digital signage market will be at 13.2 billion by 2016.
We at ClearOne continue to innovate with our digital signage products and services, as part of this dynamic market.
Digital signage has been a mainstay in our lives and this study confirms that the growth we are seeing will continue to be ever present in sectors like retail, corporate, university and many, many more.
To read more about this study, please refer to the article from Digital Signage Today or go straight to the source at MarketsandMarkets here.
Contact us today to see if we have a Digital Signage solution that’s right for your business.
If you have any questions about or products and services or would simply like to talk with us, give us a call at (541)752-5654 or send us an email to firstname.lastname@example.org
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This post continues our discussion on the value of standalone video endpoints.
Cloud-based video conferencing gives organizations the benefits of video conferencing without major investment in infrastructure or network that is often required for many deployments. Cloud-based services deliver the value of high-quality video conferencing without the upfront costs for equipment and staff that are usually needed to set up and manage video calls.
Cloud-based services make video easily accessible to anyone, anywhere whether they are using video in a room, at the desktop or on a mobile device. Video service in the cloud offers opportunities for businesses of all sizes to access video conferencing technologies in a way that is easy to use, affordable, and not dependent on in-house IT resources.
Applications For Standalone Systems
A large pharmaceutical firm used a standalone video unit when there was a need to have a subject matter expert, located in a foreign country, participate in a seminar held in the United States. The availability of a standalone video unit made it easy for the firm to connect the individual into a call. A phone line was used as a backup in case the video call failed. There was no worry about in-house infrastructure or the need to find a firm to host the call.
The value of a standalone video unit was useful to engineers from a packaged goods company who needed to immediately focus on an assembly line problem. In the past, traditional video conferencing units and in-house infrastructure issues made it difficult to handle problems with a moment’s notice. Video conferences had to be planned.
Standalone video units, with an embedded MCU, recording & streaming capabilities, make it easier to hold a video call when needed. Cloud service offerings can be used to reach outside firms (B2B) or consumer locations (B2C). Now true video conferencing portability is a reality.
ClearOne’s COLLABORATE® Room Advantages
ClearOne COLLABORATE® room solutions are standalone, serverless video units that offer best-in-class video conferencing and collaboration at a price-point and feature set vastly superior to competing room conferencing solutions. Collaborate Room systems are available for small to large sized rooms. These systems are plug & play devices that are easy to set-up, operate and upgrade. ClearOne’s COLLABORATE® offers the following advantages:
+ Self-contained, Serverless
+ Multi-standard – H.323 and SIP
+ Embedded MCU
+ Embedded Recording
+ Embedded Streaming (both uni-cast & multicast)
Deployment and usage of video conferencing systems no longer need to be difficult. No longer is there a need to invest in cumbersome in-house infrastructure, nor is there a need to deploy systems that are time consuming and difficult to install when considering video conferencing at secondary sites. Standalone, server independent deployment is now available to allow organizations to grow their adoption of video conferencing and offer easy to use, full-featured, technology. These systems are designed for small and medium-sized organizations or for secondary sites of larger enterprises.
S. Ann Earon, Ph.D., is president of Telemanagement Resources International Inc. and Founding Chairperson of IMCCA, the non-profit industry association for collaborative conferencing. She can be reached via email at email@example.com.
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Composer allows users to quickly and easily create and schedule digital signage content. Although Composer is designed for the ClearOne’s Aavelin line of digital signage players, the software is compatible with all players that put out a variety of video signals, including: Composite, S-Video, VGA, and DVI-D. This latest version of Composer also supports MPEG4 and DivX video playback.
“This is a great opportunity to continue working with our U.S. Military customers around globe” said Tom Searcy VP of Digital Signage for ClearOne. “ClearOne is looking forward to more developments in the digital signage market; providing strong solutions across a wide variety of vertical applications.”
Download MagicBox Aavelin Composer 4 CoN paper here
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As organizations continue to deploy video conferencing units in a wider variety of conference rooms there is a desire to install systems that are standalone endpoints, which don’t require the need to invest and deploy a cumbersome in-house infrastructure. Additionally these server independent units provide flexibility, immediacy and portability.
Even though there is a growing trend to desktop and mobile video conferencing, there is still significant demand to conduct conferences in pre-set rooms or executive offices equipped with dedicated devices with higher quality audio systems and cameras.
Standalone video systems can be used to host small conferences with their embedded MCU (multipoint control unit) and provide recording and basic streaming services. When needed, these systems can use cloud services for better reach and capacity for both B2B (business-to business) and B2C (business- to- consumer) use cases.
The concept of standalone endpoints marries well with the BYOD (bring your own device) trend and can reduce cost and complexity for SMB (small/medium businesses) and secondary sites for larger organizations.
In the earlier days of video conferencing many room systems were large and unwieldy appliances with complex user interfaces. This resulted in video conferencing being cumbersome and not user friendly. The appliance was eliminated from room based systems when video conferencing set top boxes were introduced. These units were easier to install and sat on top of a television monitor. Eventually there was a drive to PC-based systems with self contained codecs that worked with web cams. Software based video conferencing products were bundled with a camera and microphones.
Standalone video endpoints were initially designed to sit on the desktop for personal participation in a video call. Today these standalone video endpoints are useful in any room, on any desktop and as a mobile app. for a variety of B2B and B2C applications.
The technology has evolved from large, cumbersome systems to systems that are stand-alone and portable with all functionality bundled into the system. This evolution now makes it possible to install self-contained, full-featured video conferencing systems wherever they are needed.
Standalone video endpoints are inexpensive and easy to set up. They provide flexibility and allow for instantaneous meetings in the office or away from work (mobile and serverless), since the technology is easy to install and inexpensive enough to allow installation at secondary sites (i.e. home and smaller office sites). Users like the immediacy of the technology and are using these units for a variety of applications. No longer is there worry about cumbersome in-house infrastructure or the need for a multipoint control unit.
Until the advent of self-contained systems, organizations wishing to connect more than two sites together had to use a multipoint control unit (MCU) to make these connections. Standalone systems now have an MCU embedded in them, thus reducing the complexity and cost of using an external MCU and avoiding firewall issues.
Additionally, these units offer the value of recording and basic streaming services so information from meetings can be saved and others, at a distance, can view the meeting either as it happens or afterwards.
We’ll continue our discussion of the value of standalone video endpoints in our blog next week. In the meantime, what are your thoughts about Video endpoints? What value does it add to your clients? We’d love to read your thoughts in our comments section.
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This post continues our discussion on addressing what needs to be done with audio to make it effective in all situations so users can clearly hear everyone involved in audio and video conferencing calls.
Audio Is The Foundation
Humans can tolerate visual interference – a grainy image, untrue colors, and jerky images. But, the audio must be high quality in order for listeners to perceive the words. Decades of research have shown how specific types of signal degradation affect perception. This research has been used to produce telecommunications networks that are optimized for transmission of high quality human speech.
One study, conducted by TRI, had 100 participants view video and evaluate the quality of the image as they thought the bandwidth of the video was being altered. In reality, the bandwidth allotted to audio was changed. The participants perceived the video improving as the audio improved, even though no changes were made to the video quality.
Audio must be high quality in order for people to perceive the words. Speech can tolerate some clipping or the loss of an occasional syllable, but time lag is intolerable to listeners during conversation. When the range in the voice is muffled and speaker identity and intelligibility are affected, calls are no longer understandable. All these factors make audio quality an extremely important component of a video conference. Lowered speech intelligibility will inevitably obscure natural communication, take focus away from important aspects of the meeting, and cause fatigue.
The way audio is handled in a video call can also be an issue. The quality of speech transmitted over a local area network (LAN) or wide area network (WAN) can be impacted by the way audio packets are handled. Compression and decompression of audio is a standard part of a video conferencing system, and can be a source of reduction in audio quality. Complete loss of some audio packets during transmission over the pubic Internet may also occur. As a result, the audio signal may suffer in quality and delay. In some instances, to optimize audio in a video conference, a full duplex voice telephone circuit is used to carry the audio portion of the conference. The independent channel can also be helpful for troubleshooting if participants have difficulty with the LAN or collaboration applications during a meeting. As an alternative, a company can pay a service provider with Quality of Service (QoS) technologies like Multiprotocol Label Switching (MPLS) and Differentiated Services or DiffServ, which allow audio and video data to be transmitted with a guaranteed level of quality.
Achieving Audio Quality
The goal in any video conference is for the participants to feel they are in a meeting room with good acoustics and do not feel distracted when others whisper, tap pens or rustle papers. If a room is properly equipped and designed, meeting participants should not have to worry where they sit or stand in order to be heard. They should feel as if everyone is in the same room, even when communicating from a distance. Achieving quality audio is dependent on both the right equipment and the proper environment.
Room design is an important component for quality audio. A room with hard surfaces everywhere results in too much echo. When setting up a room for a video conference, consideration must be given to whether there are reflective surfaces near the microphones and speakers, whether there are sources of noise coming from other equipment or SS systems, and how well the room is sound-insulated from adjoining rooms. For some rooms, a premium or installed audio system may be appropriate.
Check for symptoms of bad acoustics by clapping your hands. If it sounds like you are in an empty barrel, garage or basement, you need acoustical treatment of the room. Your goal is to achieve a sound that is relaxing and inviting. The next step is to look at your meeting room and check for hard floors, hard walls and the presence of undraped windows. Hard surfaces are part of the cause of bad acoustics. The secret to making your room better for audio or video calls is to have soft surfaces that absorb sound. Carpeting, upholstered surfaces, and draperies are examples of how to soften a room to achieve better audio. But changing a room is not always practical or desired. A professionally installed system is designed by an integrator to mitigate noise and echo while optimizing desired sound.
Acoustical wall panels will also help achieve proper sound in a room. Never let two opposing walls remain without absorption. Acoustical treatment attenuates the reflected sound and increases the usable distance between sound sources and receivers. This will increase the audio quality over a wider seating area.
ClearOne’s new Beamforming Microphone Array automatically configures to room acoustics with twenty-four microphone elements, steering its pickup pattern towards participants in the room and rejecting unwanted noise and reflections.
Many systems today use simple microphones with little directional sensitivity. While these microphones capture sound from all directions, they do not adequately suppress ambient noise. New microphones are being developed to optimize directional sensitivity. Installing the right audio equipment and treating the room will help optimize audio quality.
This process does not have to be expensive. One end user solved the audio problems in a room located in a parking garage inexpensively by hanging lined draperies on the wall. The small changes worked and resulted in acceptable audio during a video conference. Small adjustments to the room can make slight audio improvements, while solutions ranging from speakerphones to professionally installed systems can bring the greatest improvements to conferencing sound.
Finally, there is no substitute for proper speech etiquette. Anyone speaking should use a normal speaking voice, with no need to shout or whisper, and always direct his or her voice at a microphone. The right audio system, with intelligence provided to automatically correct microphone gain without causing unnecessary pumping noise, is the approach to take for optimized audio. With intelligent systems presenters are able to stand or walk around a room without being tied to a lavaliere microphone or having to directly speak into a microphone.
Awareness of what needs to be done to achieve good quality audio is the key to video conferencing success. Good audio solutions for every conferencing application – with or without video – are important to successful calls.
S. Ann Earon, Ph.D., is president of Telemanagement Resources International Inc. and Founding Chairperson of IMCCA, the non-profit industry association for collaborative conferencing. She can be reached via email at firstname.lastname@example.org.
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Most business users are familiar with audio & video conferencing and have experienced both technologies in a variety of situations. But, many users forget that these technologies are only as good as the audio foundation. Audio quality can be impacted by the type of device used to participate in the calls (i.e. using hands-free devices like speakerphones or cell phones versus using non-hands free devices like telephone handsets). Too often microphones are not properly placed to hear those talking and users attempt to use a variety of audio devices, including cell phones, to connect someone into a video call. Voice quality in a video conference is impacted by the acoustics of at least two rooms – the caller and the listener. The purpose of this paper is to address what needs to be done with audio to make it effective in all situations so users can clearly hear everyone involved in audio and video conferencing calls.
Audio, that is voice, is almost always deemed the most critical portion of any conference. Without audio, the meeting loses nearly all value. A variety of equipment might be involved to hold an audio conferencing call or add audio into a video call, including telephone handsets, speakerphones for use by small groups, installed audio systems, microphones, mixers, and controllers to initialize and manage the call speakers. The quality of the voice transmission line is crucial to the success of an audio conference. A regular (analog) dialup telephone line is often all that is needed to conduct a successful audio conference. But users should be wary of individuals calling into an audio or video call on their cell phone. Both the quality of the line they are on and their location (driving in a car with a noisy truck passing them, near construction sites, etc.) can negatively impact the overall quality of the call. While many people use their telephone systems for three-way conference calls, and sometimes to even link multiple sites, a multipoint conference, of more than three sites, often requires an audio or video bridge to link sites together. A number of telephone and bridging service companies offer multipoint audio, data and video conferencing services. Calls can be established through an operator or on a dial-up basis. Keep in mind the call is only as good as the audio foundation. A noisy, hands-free conferencing connection can negatively impact the entire call, whereas video can sometimes be forgiven when lacking certain quality.
Audio Endpoint Equipment
Today, most audio conferencing endpoint products (speakers, microphones, and audio mixing controls) are full-duplex systems, providing the same kind of interaction one gets from the telephone, with important improvements.
Users can interrupt one another at any time, speaking and hearing simultaneously (known as a full-duplex call), and both users can be heard simultaneously without echo (call feedback often caused by speaker/microphone placement). Communication seems as natural as being with the person in the same room.
A properly chosen and configured full-duplex conferencing endpoint will ensure that high-quality audio is captured at the endpoint even when the room is reverberant or contains noise sources like a projector, HVAC noise, outside traffic, etc. Audio conferencing endpoints can be categorized as personal conferencing devices, tabletop conference speakerphones, and professionally-installed conferencing systems. Personal conferencing devices include one or more microphones, a speaker, and signal processors. They are designed to be used by a small group of people (one to four). Tabletop conference phones have a built-in speaker that can produce a higher sound output volume than the personal conferencing products, and they may also support expansion of the microphone pickup area through the use of expansion microphones or attachment of conference phones. Professionally installed audio systems offered today support arrays of microphones that can be placed around a large conference table to handle large groups of participants. The microphones used by professionally installed systems are generally permanently installed in the conference table or on the ceiling. There are also wireless microphone systems that are designed to use with professionally installed audio conferencing systems.
The electronics that support full-duplex audio systems process audio signals to separate the signal that originates from a local person speaking into a microphone from the sound coming from a far end talker that is played through the local speakers and is subsequently coupled into the local microphone. This is called Acoustic Echo Cancellation (AEC). Professionally installed audio systems may also include an additional technology called feedback cancellation. A feedback canceller may be required when a presenter needs his/her voice amplified into a local conference space so listeners, who may be in the same large room or auditorium, can still clearly hear the presenter’s voice. Amplification of the local presenter’s voice in the local room may result in a high-pitched squealing sound called feedback if there is positive gain between the microphone and the speaker. ClearOne’s Dynamic Automatic Resonance Eliminator (DARE) feedback eliminator uses proprietary adaptive algorithms that have evolved from ClearOne’s years of experience and expertise in echo cancellation technology. These algorithms eliminate feedback by rapidly identifying a feedback node and then placing a narrow-band filter at that frequency without the need for additional feedback elimination equipment.
For a very large auditorium, a professionally installed system may also need to include a time delay function that delays the local presenter’s voice by a programmable amount. This allows an installer to guarantee that a listener at the back of a large auditorium does not hear the presenter’s amplified voice (which is transmitted at the speed of electrical signals through the audio systems) followed by a delayed version of the presenter’s live voice (which takes longer to reach that person due to the fact that the acoustic sound travels more slowly than the electronically captured version of the presenter’s voice).
We’ll continue our discussion of effective audio for video conferencing in next week’s blog. In the meantime, we want to know your thoughts about addressing how to make audio effective in all situations for your end users. Sound off in the comments below.
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Zee Hakimoglu – CEO & President of ClearOne rings the closing bell for the NASDAQ MarketSite in Times Square.
ClearOne, Inc. [CLRO], a global company that designs, develops and sells conferencing, collaboration, streaming and digital signage solutions for audio and visual communications, visited the NASDAQ MarketSite in Times Square on September 9, 2013. In a speech, Zee Hakimoglu, CEO and President of ClearOne, said that the company is in a position for accelerated growth and in honor of the visit, she rang the Closing Bell.
View photos and video of the event here
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The Beamforming Microphone Array — Pro-Audio with beamforming and adaptive steering technology and ClearOne’s next-generation Acoustic Echo Cancellation
The ultra-sleek design fits into any conferencing environment and delivers the clearest audio pickup available with adaptive acoustic processing. Twenty-four microphone elements can steer its pickup pattern towards participants in the room and reject unwanted noise and reflections, thereby offering superb and unmatched performance for group conferencing environments.
- Beamforming & adaptive steering technology
- Next-generation Acoustic Echo Cancellation
- 24 microphone elements
- Mono and stereo modes for diverse applications
- Flexible mounting for ceiling, tabletop and wall modes
- Works with CONVERGE® Pro products: 880, 840T, 880T, 880TA
- Expandable for larger room applications by daisy-chaining up to three arrays per CONVERGE Pro unit
- Adaptive acoustic processing automatically adjusts to room configuration for best possible audio pickup
- Replaces up to 10 traditional microphones, with twice the pick-up range
- WARRANTY: 2 years, From date of purchase