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Solving 4 Common Audio Issues in Learning Environments

A good audio experience is an essential requirement in all learning environments.  Unfortunately, noisy HVAC systems, side conversations, and numerous reflective surfaces can render audio unintelligible to participants.

CHALLENGE #1: INCONSISTENT AUDIO LEVELS AND CLARITY THROUGHOUT THE ROOM
When the audio quality changes as presenters move about the room, they learn to stay in the best location throughout their presentation so they are not interrupted by remote attendees saying they cannot hear.  However, staying in place limits the presenter’s ability to engage with in-room participants.  This inconsistent audio experience is often created by misjudging the mic coverage in a room.  Too many mics can cause processing artifacts and increased reverberation, which impacts speech intelligibility.

Solution: CONDUCT AN ACOUSTICAL ANALYSIS TO DETERMINE APPROPRIATE MIC SELECTION AND PLACEMENT
An analysis should consider room dimensions, materials, furnishings and overall acoustical properties to determine the mic requirements, including pick-up range, type, quantity and placement.  Individual ceiling mics -instead of a ceiling array mic- allows mics to be placed at approximately the same distance from all in-room participants, optimizing the audio experience for remote participants.

CHALLENGE #2: UNWANTED NOISE AND REVERBERATION
Air flow and vibrations from HVAC systems can be a significant source of noise, when using ceiling mics.  Other sources of noise include side conversations, tapping on the table or keyboard, and hard surfaces, which reflect sound.  When these noises are amplified through the audio system, they can not only distract far-end listeners, but are often loud enough to compete with the presenter’s voice audio.  Too much transmitted noise results in unintelligible speech.

Solution:  USE MIC PLACEMENT AND DSP CONFIGURATION TO MINIMIZE THESE ISSUES
The distance between the ceiling mics and the table surface (where much of the participant noise is generated) gives ceiling mics an advantage over table mics.  To mitigate the effects of HVAC systems, ceiling mics should be located where the mic elements are not in the direct path of the HVAC vent air flow.  In addition, using individual ceiling mics instead of ceiling array mics allows more flexibility when determining optimum placement.  Beyond strategic mic placement, there are DSP settings that help reduce the effects of noise and reverberation. Most DSP mixers provide noise suppression and two mic controls.

CHALLENGE #3: FLEXIBLE ROOM DESIGNS
Some presenters enjoy roaming the room when speaking while others want a circle configuration instead of rows.  Participants may need to move to the front of the room to demonstrate on the whiteboard or share.  However, audio systems are typically designed to provide optimal voice pickup based on the original or fixed seating arrangement.  Once the room configuration changes, the audio system is unable to effectively accommodate their needs.

Solution:  USE CEILING MICS FOR CONSISTENT COVERAGE
To accommodate a mobile, flexible room, consider using ceiling mics that can be strategically placed to evenly cover the entire room—regardless of how the room is configured on any day. Ceiling mics offer better room coverage than table mics, allowing participants to walk around and face away from the desks or table and still be heard evenly.

CHALLENGE #4: UNWIELDY CABLES
The use of table mics often requires running cabling across the floor and under/through tables and desks to connect and power the system.  These exposed cables look bad, can be a tripping hazard, are difficult to manage, and disconnect easily.  Should the room configuration change, rerouting cables can be time consuming.  To address cable issues, some designers rely on wireless mics.  While this strategy helps reduce cables, it creates new problems, including higher maintenance due to charging stations and inventory management.

Solution:  USE CEILING MICS TO IMPROVE ROOM AESTHETICALLY
Ceiling mics reduce visible cables and are discrete enough not to affect room aesthetics.  Recent technological advancements and improvements in
mic design makes the quality of ceiling mic equals and often exceeds tabletop mic quality in many environments.

TEST

Even if a room design follows best practices, it’s important to test the system to ensure comfortable audio levels and room coverage.  Here are a few pointers on conducting an effective test:

  • Listen from a remote location to a person talking in the room.
  • Ask that person to move around the room while talking at the same level. This should be a “blind” exercise focused only on the audio.
  • Test while the HVAC system is running to determine if it creates any noise interference.
The listener at the far-end should not hear fan noises or be able to tell when the in-room person moves from one location to another in the room. The audio quality should be clear and consistent.
FINAL THOUGHTS

Modern distance learning classrooms and training rooms are flexible in how they are used, and this means audio systems need to be flexible as well.  When the four audio issues discussed in this guide are solved, participants can enjoy clear, reliable audio that enables them to learn and engage.  Every type of mic has an ideal use case.  However, in a classroom or training setting, table mics present challenges as:

  • More obtrusive than ceiling mics, creating a visual distraction for learners.
  • Create a cluttered classroom environment due to the need to run cables throughout the room.
  • Lack flexibility for participants to move around the room since table mics require the speaker to be seated or standing directly in front of the mic at all times.
  • More likely to pick upside conversations or tabletop noises such as typing, shuffling of papers, or tapping due to their close proximity to participants.

Looking for the right motorized projection screen

When a motorized projection screen is specified in a project, it is recommended to consider a tab-tensioned solution.

 

The price of a tab-tensioned motorized screen is frequently higher than a self-supported motorized screen, but it is worth the investment!The tab-tensioned screen will provide a perfectly flat viewing surface and a high-resolution image (4K, 8K, and yes, 16K).

It is important to consider that the amount of top black drop for a tab-tensioned motorized screen needs to be pre-planned.  The tab-tensioning cable relies on the complete (or near complete) deployment of the screen.  Only when completely extended does this cable pull the screen flat and hold it there for a flawless installation.  Measuring the amount of drop material needed before ordering will avoid any issues at the installation site.  If any adjustment is necessary, then it should be minimum.

Every tab-tensioned screen must have the overall width of the screen at least 1.33 times the height.   Wider is fine, but less width will lead to wrinkled corners.  If adding top drop material, then more side bordering is needed.

 

How do you do it?
 
Plan the placement of the screen case.
The height of the image should be tall enough to have the images clearly seen from the back row.
 
Plan the bottom of the screen.
The bottom of the image must be visible to all viewers without obstructions.
 
Plan how wide the screen needs to be.
The width of the image is chosen based on multiple factors such as content, projector aspect ratio and lens. As well as, if necessary to hide things or it is limited by the side walls.

Resimercial – the office and home spaces are changing

The small and private meeting areas in an office (huddle rooms) outfitted with audio and video conferencing equipment are making more sense

The commercial clients are making their home office a more appealing place to work. They are adding audio and video equipment to other areas of their homes as well.

More and more companies are planning to have staff remain working from home.

The crossover between residential and commercial integrators continues to grow.  This trend is creating new opportunities.

While the goals are the same for a commercial and a residential installation, every setting has its own set of requirements.

By nature, the demands of residential customers are normally higher than for a commercial customer.  Everyone wants to have “the best” at home!

The integrators must make sure that the products are reliable.

For the huddle room and home office, consider:

  • Discreet high-performance ceiling microphones from CTG Audio.
  • Dependable components to connect your video equipment from Luxi Electronics.
  • The right mounts for the monitors from HANGFORT.
For the residential audio and video experience, consider:
  • The projection screen, projector and speakers that will create the WOW factor from SIM2Waterfall AudioScreen ResearchSevertson Screens or The Screen Works.
  • Amplifier that produces a musical, smooth, warm, loud, clear, subtle and seamless sound from AMPED.
  • Comfortable motorized recliner chairs that will allow to enjoy the movie thoroughly from COMFORTTO.
  • The right lifts for the projector from HANGFORT.
  • Reliable components to connect your video equipment from Luxi Electronics.

Combating Ambient Light?

In terms of projection, one of the most significant challenges is ambient light.  It will impact the resulting contrast and how images appear.  Here are some guidelines to consider:

Choose the Right Screen

White screens offer optimal light diffusion properties, spreading the light uniformly across the entire surface, and in a controlled setting, this provides a vivid, clear image. However, when ambient light is present, it too, will reflect off the screen and wash out the picture.

Darker coatings, like grey or even black, work well for these environments because they provide a more intense contrast level by creating deeper levels of black, which makes the image stand out despite intrusive light.

ALR (ambient light rejecting) surfaces are designed to redirect off-axis light (light other than that emitting from the projector) away from the viewer’s field of vision.

Gain screens, surfaces on which optical coating is applied to increase reflectiveness, can also improve on-axis brightness and redirect a certain amount of off-axis light away from the viewer.

Don’t Overlook the Projector

The loss of brightness resulting from a darker low gain surface is compensated by a higher lumen projector.

While the right projection surface choice is the main factor in controlling the effects of ambient light, higher lumen output projectors are great for brightly lit spaces because the projected light is bright enough to overcome other light sources and compensate for reduced reflectivity from the viewing surface.  However, if the projector is too strong, it will negatively affect contrast and cause an uncomfortable glare for the eyes.

Create the Optimal Viewing Environment

One of the easiest changes to make is painting the room to a darker color to reduce its reflecting capabilities.  Also, consider installing light-blocking window shades.

While it may not be possible to blackout the entire space, it is important to diffuse or eliminate any light that’s coming from behind the projector, especially if an ALR surface has been selected.

Ambient brightness throughout the room can be controlled using directional overhead spotlights. This keeps light away from the projection screen.  Another idea is to incorporate individualized lighting, rather than relying on lighting fixtures that apply broad coverage throughout a room.

An unobtrusive giant TV ?

4K HDR SIM2 xTV

A new way to watch TV on a really big screen (up to 2.65m wide) that integrates with home interiors. Just need to position the projector close to the wall or the screen on which it will project.
Features:

✓ 4K UHD DLP projection technology “3840*2160 pixel”
✓ LASER illumination system with 2 color wheels
✓ HIGH BRIGHTNESS of 3,200 lumen
✓ Expanded COLOR space up to 84% DCI-P3
✓ Superb HDR processing and HDR10
✓ POWERFUL INTERNAL AUDIO (2 x 15W 2 ways + bass reflex)
✓ Bluetooth AUDIO connection to external active speakers
✓ WIRELESS video connection and MIRACAST
✓ WIFI & Operative system
✓ De-Judder video processing for motion
✓ Automatic Ambient light adapting
✓ Crystal glass & Aluminum CABINET
✓ Automatic wireless update of the projector software