What Is A Microphone Array?

The use of technology in the classroom is becoming increasingly prevalent in today’s educational landscape. As schools and universities adopt new and innovative solutions to enhance the learning experience for students, one area of focus has been improving the quality of audio in the classroom. The DDMC recently sat down with Steven Pretzer, an AV support tech at Fuqua School of Business, to discuss the installation of three new microphone arrays in the McClendon and HCA classrooms. In this article, we will explore the benefits of microphone arrays over traditional tabletop microphones, the challenges of implementing them in a classroom setting, and best practices for their use.

  • What is a microphone array, and how does it differ from traditional table microphones?

 A microphone array is a microphone system that uses multiple microphones arranged in a specific pattern to capture audio in challenging acoustic environments. It uses beamforming technology to enhance sound coming from specific directions while reducing unwanted background noise and reverberation. The microphones are combined to create a virtual microphone that can be aimed and steered to capture audio from a particular area. It is often used in situations where multiple speakers are present, such as in a panel discussion or a classroom lecture and can provide high-quality audio for remote participants in video conferencing systems.

 A microphone array differs from a tabletop microphone in several ways. First, a microphone array is typically mounted on the ceiling or wall and can capture audio from multiple directions simultaneously, while a tabletop microphone only captures audio from a single direction. This allows microphone arrays to pick up a wider range of sounds and voices in a classroom setting, improving the overall quality of audio.

  • What are the benefits of using microphone arrays in a classroom setting?

 Using microphone arrays instead of tabletop microphones in a classroom setting offers several benefits, including the ability to capture sound from a wider area, reducing background noise and reverberation, being more discreet, and being more cost-effective in the long run. This enhances the learning experience for students and teachers alike by providing clear and intelligible audio in a range of challenging acoustic environments.

  • How do microphone arrays improve the quality of audio in a classroom environment?

 Microphone arrays improve the quality of audio in a classroom environment by providing clear and intelligible audio that can be easily understood by students and teachers. This is achieved through a combination of features, including the ability to capture sound from a wider area, reducing background noise and reverberation, and the ability to steer and focus the audio in real-time towards the person speaking. In contrast, traditional tabletop microphones can often be garbled and difficult to distinguish between speakers, particularly in larger classrooms or lecture halls. By using microphone arrays, the need for additional equipment, such as lavaliere microphones, can also be reduced, resulting in a simpler and more streamlined audio setup that is easier to manage and maintain. Overall, the use of microphone arrays can significantly enhance the quality of audio in a classroom environment, improving the learning experience for students and teachers alike.

  • What are some of the challenges associated with implementing microphone arrays in a classroom, and how can they be addressed?

 Implementing microphone arrays in a classroom can present several challenges that need to be addressed to ensure optimal performance. One of the main challenges is the complex acoustic environment of a classroom, which can include a variety of sound sources, such as students talking, moving around, and rustling papers. In addition, the shape and size of the classroom, as well as the placement of the microphones, can also affect the quality of the audio captured.

 To address these challenges, it is important to carefully plan the installation and setup of the microphone array system. This may involve using specialized software to analyze the acoustic environment and optimize the placement and configuration of the microphones. It may also involve walking the room and testing the system to ensure that it is capturing clear and intelligible audio from all areas of the classroom.

  • What factors should be considered when selecting a microphone array for a classroom setting?

 Installation type and location, backend interface. All play into the choice.

When selecting a microphone array for a classroom, factors such as installation type and location, backend interface, size and shape of the room, number of students and teachers, and the acoustic environment of the room should be considered. Ceiling-mounted microphones may offer wider coverage and be more discreet, while wall-mounted microphones can provide better directionality and control. The interface should be compatible with the existing audio system and any additional equipment that may be needed. Advanced noise reduction capabilities may be necessary for classrooms with high levels of ambient noise. By carefully considering the specific needs of the classroom and the capabilities of different microphone array systems, schools and universities can select a system that provides clear and intelligible audio for students and teachers.

  • How do microphone arrays improve the learning experience for students and teachers?

 Clarity, Clarity, Clarity!

 Microphone arrays can greatly enhance the learning experience for both students and teachers in the classroom. They improve the clarity of audio, reduce the need for repeating questions, and help the classroom flow more smoothly. Microphone arrays can create a more inclusive learning environment, making it easier for all students to hear and understand what is being said. This is particularly beneficial for students with hearing impairments or those who may struggle to hear in a crowded or noisy classroom. Overall, microphone arrays can greatly enhance the learning experience in the classroom by improving audio quality and creating a more inclusive environment.

  • Why use ceiling mounted microphone arrays in a classroom?

Ceiling-mounted microphone arrays can offer superior audio quality compared to other types of microphones, thanks to their advanced beamforming technology. This technology allows the microphones to focus on the speaker and filter out unwanted background noise, resulting in clear and intelligible audio for all students. While other types of microphones, such as wall-mounted or portable microphone arrays, may be suitable for certain classrooms, ceiling-mounted microphone arrays offer several key advantages that make them a superior solution for most classroom environments. By providing wide coverage, reducing disruptions, and delivering high-quality audio, ceiling-mounted microphone arrays can greatly enhance the learning experience for both students and teachers.

  • What are some best practices for using microphone arrays in a classroom setting?

A In line ducker in the DSP. Gain Structure. Focused on speech. High Pass filters. NOM limit of 1 with the ceiling arrays to keep the noise floor low and a lower hold time on the gating auto mixer to ease the transition between open mics.

 If something you’re doing is not making it better? Don’t do it!

 To optimize the use of microphone arrays in a classroom setting, there are some best practices that should be followed. Firstly, it is important to use an in-line ducker in the DSP, which will automatically lower the volume ofany background noise when someone is speaking. This can greatly improve the overall audio quality and intelligibility.

Secondly, attention should be paid to gain structure, ensuring that the microphones are set at the appropriate level to capture speech without picking up unwanted noise. Additionally, the microphones should be focused on speech, with any background noise or reverberation minimized using high-pass filters.

 Finally, it is important to remember that if a certain adjustment or change is not making the audio quality better, it is better not to do it. This can prevent unnecessary tinkering and ensure that the microphone arrays are being used in the most effective and efficient way possible. By following these best practices, the use of microphone arrays in a classroom setting can be optimized, resulting in improved audio quality and a more effective learning environment.

 Additionally, the advanced beamforming technology of microphone arrays allows them to filter out unwanted background noise, resulting in clear and intelligible audio.

 When selecting a microphone array for a classroom setting, factors such as installation type, location, and backend interface should be considered. Ceiling-mounted microphone arrays are often a superior solution, thanks to their wider coverage and advanced beamforming technology, but other types of microphones may be suitable for certain classrooms.

 To optimize the use of microphone arrays in a classroom setting, best practices such as using an in-line ducker in the DSP, paying attention to gain structure, and minimizing background noise using high-pass filters should be followed. By following these best practices, the use of microphone arrays can be optimized, resulting in improved audio quality and a more effective learning environment.

The use of microphone arrays in a classroom setting can greatly enhance the learning experience for both students and teachers. By providing wider coverage, reducing disruptions, and delivering high-quality audio, microphone arrays can ensure that everyone in the classroom can be heard clearly without the need for passing microphones around.

Meet Steven Pretzer

A skilled audio engineer and AV support tech at Fuqua School of Business. With a degree in Recording Industry Production and Technology and a minor in Mass Communication, Steven’s passion for audio began at an early age. After working as a freelance audio engineer in Nashville for several years, Steven moved to Chapel Hill in 2008 where he focused on playing bass in several bands and continued to do independent recordings from his home studio.

In 2017, Steven became a contractor at Fuqua through Duke temporary services and in 2019, he was hired in the position of AV support tech at Fuqua. As an AV support tech, Steven’s primary job is to support faculty, staff, and students regarding classroom technology. Utilizing his background in audio engineering, Steven has been able to focus on and improve communication in Fuqua classrooms.

In addition to his experience, Steven has received several Biamp certifications including Tesira Forte and Tesira Servers as well as Dante level 1. With his expertise in audio and classroom technology, Steven has been able to implement microphone arrays in Fuqua classrooms, greatly enhancing the learning experience for both students and teachers.

Wolfvision and The DDMC


Welcome to today’s presentation! Here we have WolfVision Cynap Pro! This wireless presentation and collaboration system is available worldwide with an output resolution of up to 4K UHD. It has a Linux operating system and supports devices for wireless mirroring such as iOS, iPadOS, Android, Windows, macOS, Chrome OS and more.

Cynap Pro plays, displays, records and streams all commonly used media at the same time giving you unlimited choice of materials during presentations, lectures, and active learning classes. You can access your data easily via cloud, network drive or from mobile devices – even your laptop is no longer essential – you can simply bring your content on a USB stick.

It also lets you record all your multi-window multimedia content. Everything is captured in high definition and saved internally – perfect for use as part of your online educational program. The included Capture feature pack enables operation as capture agent for Panopto and other compatible video management platforms.

In common with other Cynap systems, the Cynap Pure Pro comes with 4K output resolution, up to 4 window on-screen display and free-of-charge firmware updates and remote management tools. Both customizable and prepared API modules are also available enabling easy room control system integration.

The DDMC had a great turn out for the in-person presentation of WolfVision Cynap Pro. The attendees were impressed by its features such as recording all multi-window multimedia content in high definition which can be saved internally for use in online educational programs.

We were joined by WolfVision’s Innovation and Product Managers Andreas Ganahl and Fabian Hirschauer for presentation of WolfVision solutions and sneak-peak at upcoming roadmap! They presented WolfVision solutions that are designed to enhance collaboration in meeting rooms, classrooms or lecture halls.

I would like to extend a big THANK YOU to the Multimedia Team at the Fuqua School of Business for their hospitality!

That’s it folks! Check out our Panopto recording for more details!

Zoom White Board

Duke University is evaluating the new whiteboard feature offered by Zoom, and already recommending it to faculty members. I received great insight from DLI about the new feature, and the university is optimistic about its potential. The new feature includes templates that aim to recreate real-life use cases, such as project management and agile methodologies. The whiteboard feature offers an interesting step forward, however the implementation may work better with standalone PM tools. Duke University is also looking into creating custom templates that would be more suited to their specific needs.

The integration of the whiteboard feature with Canvas and LTI Pro is being closely monitored, as the university is in the process of migrating to Canvas. The integration is slightly more robust in Canvas and includes a new whiteboard tab. The university is also evaluating Padlet, a faculty-preferred teaching tool, as a complementary tool to the Zoom whiteboard. There is a wide variety of use cases for virtual bulletin boards, and research has already been published on the topic. With the great insight from Chris Lorch at DLI, Duke University is optimistic about the new whiteboard feature from Zoom.


Sony Electronics

Sony brought some of the industry’s leading technology to Duke for members of the Duke community to view, touch and explore at the Bryan Center Studios for a limited time.

The event was open to all faculty and staff at Duke University, Duke Health and members of the Durham community.

Electronics include:

  • Crystal C-Series LED Video Wall — Micro LED display and video wall that uses cutting-edge picture-processing technologies to allow you to create extraordinary, large-scale, “ultra-real” visual experiences with clarity, contrast, and color.
    • Follow this link to the start of the CLED Demo
  • Sony FX9 video camera – A full-frame 6K sensor camera with Fast Hybrid AF, Dual Base ISO, and S-Cinetone™ color science, produces cinematic picture quality.
  • PTZ and Remote Cameras – Built for any space, these cameras and accessories use advanced technologies for remote lectures, meetings and presentations and can integrate easily into most standard systems with simple installation.
  • NUCLeUS – A scalable digital imaging platform for hospitals and ambulatory surgical centers, it streamlines the management and distribution of video content – plus still images and patient data.

Access the entire video here: Sony DDMC

Wolfvision CYNAP Pro

App-free dongle-free screen sharing!

Connect and share your screen using the wireless technology that’s built into your own mobile device. Our wireless BYOD solutions suit all iOS, iPadOS, Android, Chrome OS, Windows and Mac devices – with full support for AirPlay, Chromecast, and Miracast screen mirroring.

Record your content

Cynap Pro lets you record all your multi-window, multimedia content. Everything is captured in high definition and saved internally – perfect for use as part of your online educational program. The included Capture feature pack enables operation as capture agent for Panopto, and other compatible video management platforms.

Multi-platform web conferencing

Cynap Pro‘s multi-platform web conferencing solution runs directly on the device itself, and is designed to solve many of the issues most commonly experienced with BYOM web conferencing systems.

Complex multi-step setup, and bandwidth issues are eliminated, and Zoom, MS Teams or WebRTC-based wireless conferencing sessions are easily started and controlled, using a simple workflow, from a touchscreen, or any laptop, smartphone, or tablet.

Stream & record to mobile

Our unique vSolution App for iOS, iPadOS, Android, and Windows lets your audiences receive and record a live stream of presentation or lecture content from Cynap Pro onto their own smartphones and tablets.

Freedom to present

Cynap Pro plays, displays, records, and streams all commonly used media at the same time, giving you unlimited choice of materials during presentations, lectures, and active learning classes.

Access your data easily via cloud, network drive or from mobile devices – even your laptop is no longer essential – you can simply bring your content on a USB stick, or download it directly from the cloud!

Annotate over any open window

Add to your content material using our built-in annotation features – or note down your ideas using the digital whiteboard, and save the output of both for future use.

If you are looking for an all-in-one with only needing to add audio processing? The CYNAP line of products is a good way to go.

A New Kind of DDMC

Bryan Center Studio 1

We had great attendance for this DDMC meeting! Featuring a lineup of big hitters and an all-star cast in the gallery at Studio 1 made for a great event. A big thanks to everyone for your support!

Richard Mitchell made his return to the DDMC, wearing a well fitted Biamp Vest, to give us a rundown of the new Parle’ VCB2500 video bar that is shipping! He also provided overviews of Biamp’s new AV control product line, Video conference cameras, Devio conferencing, and an easy to use classroom designer. The Biamp product line does an excellent job of covering all of your educational technology needs.

Michael Greene and Chris Lorch from Duke Learning Innovation discussed the impact of digital learning technologies on the classroom and other learning environments and showed how active learning helps students think, create, discuss and solve problems rather than passively sitting in a class receiving information. They highlighted the use of whiteboarding to promote brainstorming and group work. Reducing the need for podiums, providing good sound and visuals, and promoting more instructor interaction with online students are all components that should be considered in this new landscape of HyFlex teaching at Duke University. DLI is Duke’s resource for faculty and staff to tap into the opportunities that hybrid teaching tools can provide.

John Ballinger and Tim Hunnicutt with Panasonic brought an impressive array of PTZ cameras, video switchers and auto-tracking technologies to studio 1. John spent some time featuring Panasonic’s auto-tracking, which uses high-performance motion detection and high-accuracy facial recognition. These features allow precise tracking of the subject with minimal tracking errors, regardless of the direction the person is facing, even when the lecturer has his/her back to the camera. In addition, since this function provides detection/tracking with streaming video from the camera, the video capture board typically needed for capture on a PC is no longer required. This reduces the processing load for video capture, thereby eliminating the need for a high-performance PC. I also want to note the new PressIT 360, an easy to use plug and play conferencing camera ideally suited for small collaboration spaces.

Finally, our own Stephen Toback presented a topic near and dear to his heart: How to build a 4k studio for under $4,000. Knowing that the Bryan Center Studios will not always be convenient or the right place to shoot your video, Stephen put together a concise list of features your 4k studio should have in order to be successful. Room size, shape, acoustics, and lighting should all be considered before purchasing cameras and microphones. Stephen’s 4k studio equipment list details everything you need to outfit a studio of your own.


For more detailed information, please check out our Panopto recording of this event.



We had great turnout for our July 27th DDMC presentation with the kind folks at Crestron Electronics. Representatives Ryan Bernt and Greg Coddington showed up with a wealth of information. New and improved online and in person training, camera tracking, BYOD product updates, and cloud based control platforms.


Be sure to check out the recording for more details!

Crestron at the DDMC

Extron Electronics

Mark Bednarcik & Don Mitchell with Extron Electronics dropped into the DDMC and gave us a run down on some of the powerful tools that Extron has available for Collaboration spaces, Conference Rooms, and Lecture Halls. Also highlighting control and their new Virtual Control platform that will allow control of up to 50 rooms on one box.

Mark and Don pointed out the expansive online and in-person training that Extron offers. Worth checking out! Especially if your are in need of CTS or BICSI continuing education credits.

If you would like to review the meeting please follow this link to the DDMC Panopto to this video!

Panasonic Education Solutions

The DDMC met with our good friends at Panasonic this afternoon. All of us know they provide high quality classroom projectors. We just now discovered is they have a “pimp my projector” option with custom vinyl wraps! Custom Graphic/Logo/Colors. A 5-10 day Business day turnaround will get you stylin n’ profilin before the fall semester!

Also new to the Panasonic line of education products is their entry into wireless microphones with (11) new products that aim to be intuitive to use, lightweight and secure. Designed for lecture halls, auditoriums, the system has the flexibility to deliver excellent quality in spaces small too large.

New and notable is the Panasonic Lecture Capture & Auto – Tracking system. An all-in-one system to automatically track, record and stream video. Delivering a high quality, rich multi-source viewing experience. Co-developed & certified with Seneca and Panaopto for plug and play capabilities that should make for easy integration into existing AV systems. I have requested a (4) camera on site demo! So, stay tuned for further developments.

Check into our Zoom call here

2022 Northwest Managers of Educational Technology Conference Summary

This April I attended the Northwest Managers of Educational Technology conference held this year in Coeur d’Alene, Idaho. Since there’s nothing quite like this group in the Southeast, it felt well worth it to me to fly across the country to enjoy a little normalcy and connect in person again with fellow A/V professionals focused on education. Of course, I can’t deny that the location for this year’s event on the shores of beautiful Lake Coeur d’Alene was an added draw. The conference was well attended (I’m guessing ~100 attendees), and exceptionally well run. NMET is a close organization with a history that spans several decades going all the way back to the beginning of the AV industry as we know it in the era of analog media.

Lake Coeur d'Alene


  • Responses to the pandemic and various school’s efforts to work toward a “new normal” 
  • The CARES Act as a catalyst for A/V classroom upgrades: UNLV launched a huge new program during COVID called RebelFlex using CARES funds that is seen as largely successful that would likely not have been possible otherwise. (Duke, along with several other top private universities such as Harvard and Princeton chose not accept CARES act funding.)
  • COVID as a driver for A/V initiatives and standardization: Many schools saw decision-making for A/V and IT-related projects shift to the provost level and higher as schools developed alternative teaching strategies such “emergency”, “HyFlex,” “hybrid,” “co-mingled,” and remote teaching as pandemic responses. In most cases timelines for implementing major A/V projects sped up significantly as well.
  • COVID as a driver for A/V standardization: Oregon State University described how COVID helped their campus standardize on an enterprise A/V strategy that centered on Kaltura, Canvas, and Zoom, and quieted demand for competing tools. Interestingly, OSU does not use a dedicated recording tool such as Panopto but instead utilizes Zoom for all recording and pushes this content to Kaltura within Canvas course sites. 
  • Faculty support models for hybrid teaching: UNLV’s RebelFlex program experimented with hiring students who were assigned to in-person classes as tech support. While overall this seemed successful, there were challenges, such as the diminishment of the need for tech support as the semester went on and faculty became familiar with the new technologies involved. Additionally it was observed that faculty members tended to morph the roles of their student help into roles resembling TAs and research assistants over time, including using these helpers as moderators for their Zoom chats.
  • Building a Networking Group like NMET: Some of the conference attendees were surprised I came all the way from North Carolina to attend the conference. “You mean the Duke?” several asked. I explained there’s nothing in the southeast comparable to NMET, an education-driven organization focused on the intersection of A/V and IT. That’s sad, but not surprising in a way, since a successful organization like NMET isn’t built overnight. NMET began holding conferences in 1979 and is the result of the hard work and passion of several generations of A/V professionals who have comprised NMET.
  • The A/V Superfriends Podcast (https://www.avsuperfriends.com/): Some of the members of NMET together with other A/V professionals extending beyond that group maintain a very cool podcast for A/V professionals focused on the intersection of A/V and pedagogy in higher ed. They were actually recording new episodes of the podcast live in the exhibit area. Members of this group led several interesting conference sessions focused primarily on the impact of COVID for classroom technology. Recent topics of their podcast include: 
    • Managing PO’s and supply chain issues
    • Campus support structures
    • Auto-framing and auto-tracking cameras
    • Cabling infrastructure and TIA standards
    • The intersection of A/V and IT in hiring new staff
    • AV replacement cycles–do we set arbitrary schedules of 5, 7, 10 years or tie AV refresh projects to capital projects?
    • Bootstrapping light video production switchers into classroom systems
  • AV over IP: It was argued by some that the NDI (Network Device Interface) protocol represents the wave of the future, and that we should future-proof our classrooms by purchasing NDI-capable cameras
  • Benefits and drawbacks of Zoom certification: It was discussed this may be OK as long as not mandated or exploited for commercial benefit (cross reference Tandberg)
  • “Hybrid” (instructor-driven) vs. “HyFlex” (student-centered) classrooms
  • USB as the “common language of hybrid learning spaces”
  • Elevating sound quality in the rush to add A/V infrastructure to classrooms 
  • Keeping classroom AV UI’s simple and standard even in classrooms where there is great complexity under the hood
  • ePTZ (auto-tracking) cameras: Importance of good lighting, fixed positions are better than continuous tracking
  • Making a virtual lightboard: One presenter showed how he used Procreate and a green screen in front of presenter to make a virtual lightboard 


  • Kaltura: Kaltura was one of three main sponsors of the conference. As mentioned above, Oregon State University, which was the main organizer of the conference, is a Kaltura customer. It was noted that Kaltura, unlike most other vendors, still offers an unlimited storage and bandwidth licensing tier, although it was mentioned it is “expensive.”
  • Panasonic: Panasonic was another major sponsor of the conference. Their projectors and displays were used in conference venues.
  • Elmo was showcasing its wide array of document cameras from a $200.00 USB to similarly portable wireless options starting at ~$800.00 to its flagship 4K, 12x optical zoom version designed for fixed classroom installations, the PX-30E (MSRP $3700.00). Interestingly, while WolfVision is the 500lb gorilla in the doc cam space, Elmo actually invented the document camera, and is the older company.
  • Epiphan was showcasing its well-known Pearl live encoder lineup along with its cool new device, the LiveScrypt. The LiveScrypt connects to Epiphan Cloud to add live ASR-based captions to your live production. These captions can be embedded with your live streams or sent out to monitors in the room for display for in person or hybrid events. There is a charge of $10.00/ hr to use the cloud-based ASR service in addition to the $1,500.00 cost of the device itself.
  • Alfatron had its wide range of PTZ cameras on display, ranging from a MSRP of $700.00 to $2150.00.
  • Shure had a booth showcasing equipment by Stem, a company they recently acquired. Stem offers complete solutions for outfitting conference and meeting rooms with a range of mics, including tabletop, wall, and ceiling mounted ones, together with a hub and an integrated control system for managing the individual elements.
  • Smart was demoing its latest lineup of interactive displays
  • Legrand AV showcased a wide range of products focused on physical classroom infrastructure, including displays, display mounts, projectors, PTZ cameras, speakers, device controllers, and network switches. Legrand is a large company that owns Vaddio, Chief, Da-Lite, and Middle Atlantic Products.
  • Cleardigital featured its modular display wall called Vue featuring very smooth touch surfaces and replaceable panels as well as other products such as a PTZ cam, the RL400, a portable doc cam and an all-in-one conference camera.
  • Newline Interactive was featuring its newest interactive and non-interactive displays ranging from 27” to 98”
  • AVer gave a conference session demo-ing its new autotracking PTZ camera, the TR333V2. The TR333V2 offers:
    • 30x optical zoom
    • Sophisticated pre-set configuration, including the ability to move in and out of continuous tracking and fixed position mode based on how an instructor moves in the classroom
    • 4k
    • 3G-SDI, HDMI, IP, and USB output 
    • Full or half body tracking