Audio Feedback vs. Echo – What’s the Difference?

August 9th, 2012 | Posted by Lisa Avvocato in Audio Visual Integration - (0 Comments)

There it is again, that unbelievably annoying high pitched sound. What is it? One person says it’s an echo, another person says it’s a reverberation and yet someone else is saying it’s feedback. All I know is it’s driving me absolutely crazy and somebody just needs to make it stop!

If you video conference on a regular basis, chances are you’ve been in a similar situation. People are throwing around different terms left and right then arguing over whose side is at fault. With all of this going on it can be difficult to determine exactly what the problem is let alone how to fix it.

Here’s a quick overview to help distinguish between echo, reverberation and feedback along with some tips to help reduce each one. 

Echo, also known as reverberation, is almost always a problem on the far end of a video conference and is the result of a reflection of sound. When a participant speaks into a microphone, the audio gets transmitted to the other side through their speakers. Then, their microphone picks up the audio and sends it back to the speakers in the local room. Participants in the local room hear what was just said again since the speakers on the far end are not cancelling out the audio properly.

To minimize reverberations, an echo canceller or acoustical ceiling tiles can be installed. Additionally, minor adjustments to the type and placement of room furniture along with the installation of shades or a heavy rug can help improve acoustics in the room.

Audio feedback, on the other hand, is almost always an issue with the local room. It occurs when a sound loop exists between an audio input (microphone) and an audio output (speaker). Essentially, when a participant speaks the audio passes through a microphone to the speakers and gets amplified. The process continues to repeat as the microphone picks up the noise, amplifies it further, and passes it through the speaker. Eventually a sound, ranging from a low pitch to an extremely high pitch, is emitted which can disrupt the conference in addition to be extremely annoying.

To minimize feedback, microphones and speakers should be spaced appropriately and positioned so the speaker output isn’t feeding directly into the microphone. Additionally a digital feedback eliminator or noise filter can be installed to reduce feedback.

Audio quality plays a significant role in the video conferencing experience and should not be taken lightly. Poor audio can detract from the effectiveness of the meeting as participants are focused more on trying to hear speakers and tune out background noises than on the topics being discussed.

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Can You Hear Me Now?

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Can You Hear Me Now?

August 1st, 2012 | Posted by Lisa Avvocato in Audio Visual Integration | Video Conferencing - (0 Comments)

There are several different components that go into designing an optimal collaboration space: displays, video switching, control system, lighting, the list goes on. But what about the acoustics, how do you ensure both local and remote participants can hear each other clearly?  Believe it or not, there are actually several factors that affect the sound quality in a room.

Speaker and Microphone Placement:
Room design and they way participants actually use the space must be considered when designing audio pickup and coverage in a room. The style of meetings, along with furniture placement (tables/chairs/displays/etc.), allows a design engineer to determine the best type of microphone and final microphone placement. Most audio visual rooms now perform multiple roles; a single room can be used as boardroom in the morning, then a training room with remote participants in the afternoon. Therefore, microphones may be placed in the ceiling with a wireless lapel and handheld support. This allows multiple room configurations while keeping the technology in the background; allowing the meeting in each scenario to take precedence. Additionally, the speakers selected should allow for full and even coverage of the space; supporting audio from participants, DVDs or PCs.

Room Acoustics:
The acoustics of a room are determined by the room environment; such as room size and shape, ceiling height, surface materials (wall/floor/ceiling) and participant seating locations. The microphones, speakers and screen surfaces may also add a positive or negative acoustical impact into the room. Additionally, noise generated from an HVAC system must be taken into consideration when designing a collaboration room. A noise diffuser can be used to minimize air handler noise in the room.

Reverberation:
Sound reflections can be attributed to the shape of the space, as well as, surfaces located in the room. Hard surfaces, such as paneling, concrete, doors and whiteboards can reflect sounds creating echo and secondary audio throughout the room. Small adjustments to room shape or absorptive surface treatments placed in strategic locations, along with an echo-canceller, can help eliminate reverberation and reflection issues in some of the more difficult spaces.

Windows and Doors:
Background noise can be extremely distracting to both remote and local participants. Selecting windows and doors that minimize outside sounds can help keep participants focused and ensure clear audio is delivered to remote participants. Wall and ceiling structure should also be considered during construction, this will ensue that the meeting stays in the room and does not “leak” in to the next meeting room or the hallway. Additional ceiling insulation, double walls, or specific sound absorbing material can be installed for corporate privacy or high noise areas.

Additional Resources:
Audio Visual Buyers Guide
Let There Be Light

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Top 5 Conference Room Considerations

July 12th, 2012 | Posted by Lisa Avvocato in Audio Visual Integration - (0 Comments)

Conference rooms play a major role in any organization. They’re where presentations are made, ideas are formed and innovation happens. Management teams go to discuss business strategy, work teams go to collaborate on projects, business partners go to discuss relationships, and sales representatives go to court clients. The bottom line is conference rooms are where business happens. Therefore, it is very important to consider the factors that make a space conducive to meetings.

Before designing and implementing an audio/visual integrated room it is important to take some time to consider the meeting space itself, where the room will be located in your building, and some of the key components of the room:

Location: Conference rooms should be located in low-traffic areas to minimize background distractions and maintain confidentiality. Soundproofing or speech privacy solutions can be used in busy areas to mitigate unwanted noise and preserve privacy.

Acoustics: A conference room’s acoustics ensure an optimal audio experience for both in-room and remote participants. The room’s size and shape, as well as, surface materials (walls/floor/ceiling) can lead to reverberations or echo. In some cases, noise cancellation devices may be needed to improve audio quality.

Doors & Windows: Too much direct sunlight can become uncomfortable, not to mention blinding, for participants. Additionally, glass windows and doors tend to let in more outside noise which can disrupt a meeting. Blackout shades and solid doors can be used to minimize light and background noise.

Furniture: Proper seating arrangements must be designed to provide optimal viewing and comfort for each participant. If video conferencing will be integrated, furniture should be chosen that minimizes the glare on cameras.

Power: A conference room should have a few dedicated circuits to power all equipment (displays, projectors, video conferencing, etc) along with convenient ports for participants to plug in personal devices.  There should also be enough power to handle any HVAC systems that will need to be added to the room to support larger numbers of participants.

Many of these areas of concern can be adjusted in the selected room space, However, selecting a room space that meets many of the above criteria can help to reduce costly room remediation and provide an environment that will be far more conducive to meetings.

Additional Resources:
Audio Visual Buyers Guide

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iPad Meets Audio Visual Integrated Room

June 13th, 2012 | Posted by Adam Kaiser in Audio Visual Integration - (2 Comments)

iPads are everywhere! Enterprise. Education. Not-for-profit. The place I get burritos…

Due to the iPad explosion, more and more organizations are looking to create iPad  applications that can help run their business. IVCi’s team of AV gurus has taken it one step further, creating an iPad application that can actually run your conference room or boardroom. Through some clever programing and a deep understanding of AV technologies, it is now possible to control every aspect of an AV integrated room from the touch screen of the iPad. Need to adjust the lighting or shades? No problem!

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A Little CTS 1300 Magic

June 5th, 2012 | Posted by Lisa Avvocato in Audio Visual Integration | Cisco | Telepresence - (2 Comments)

What happens when you put a Cisco CTS 1300 and a couple of super genius IVCi audio visual designers in the same room?

A panoramic camera view that allows all three room segments to be captured, as well as, auto switches to the person speaking for a close up view.

With the help of several magic boxes, a few third party tools, and a whole lot of IVCi ingenuity, this truly unique design enables collaboration by not only allowing participants to view the presenter, but to view the other participants reactions.

Now you can easily bounce back and forth between meeting participants without losing sight of what really matters!

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