Home Theater Meets Home Conferencing
As a supplement to the “Inside the Minema” podcast episode, I thought it might be helpful to share some details of the conferencing system configuration in my home cinema (dubbed the “Minema” for Mini+Cinema), together with some lessons I learned along the way. Hopefully this will be a useful reference for Cineluxe readers who may have similar objectives for making the most of their entertainment spaces, particularly given the increased demand for conferencing capabilities in the home as a result of the pandemic. There are no doubt other ways of achieving the same objectives, but I hope this overview can help inform discussions clients will have with their integrators about their own installations.
One of the things I like about the overall design for the Minema is that none of the conference-room functionality is visible when you walk into the room. The conferencing equipment (e.g., the camera, mini-PC, and microphone) is either stored inside purpose-built cabinetry on the screen wall or mounted on the ceiling behind acoustically transparent fabric. LED lighting for videoconferencing is also hidden behind hinged doors on both sides of the screen. Other conference-room features, such as connectivity for laptops (projector display, ethernet, power), are built into small discreet cabinets tucked behind the seating armrests.
click on the image to enlarge
VIDEO- AND TELECONFERENCING SYSTEM
The schematic above depicts the core elements of my videoconferencing and teleconferencing system. Here are some of the key design decisions reflected in the final layout:
In order to avoid problematic camera angles from above or below the screen, the camera is positioned in cabinetry to the right of the screen to get it more in line with the face height of anyone sitting in the theater seats. It is installed on a small custom-built shelf with an articulating arm so it can be stowed away when not in use. I use my Lumagen Radiance Pro video processor to shrink the projected video image onto the bottom right corner of the screen to make it easier for meeting
participants to look in the camera’s direction while watching the conferencing image on the screen. The Logitech Rally PTZ (pan/tilt/ zoom) camera is easy to control and the resolution is excellent even when zooming in on the faces of meeting participants in the center seats.
Use of Ceiling Microphone
The Shure MXA910 ceiling-array microphone (shown at left) came highly recommended by several conference-room integrators. I’ve found that it picks up everyone’s voices well regardless of where
they’re sitting, but by definition any ceiling microphone will struggle to compete with the quality of a headset microphone or other microphones that can be placed closer to someone when they’re speaking. The ceiling microphone is great for its wide coverage and its invisibility, so this was a compromise I was willing to make.
One unintended benefit from an early design decision to use Wisdom line-source speakers for all seven horizontal channels in the Minema is that I have very little acoustic treatment in the ceiling. This left plenty of room in the area above the seats for the microphone (which is surprisingly large) and a WiFi access point.
Location of Mini-PC (for videoconferencing codecs)
Although my conference-room integrator initially proposed putting an Intel NUC in the equipment rack, we ended up moving it to the screen wall to make for a much shorter cable run to the 4K camera, which requires a USB 3.1 connection.
I primarily use the NUC with Zoom Rooms Conference Room software to host my meetings, which has the advantage that I can use the companion Zoom Rooms controller iOS app on the iPad Mini I use as the main Crestron controller for the theater. If I need to join a meeting hosted on another conferencing platform, it’s simple to exit the Zoom Rooms software on the NUC to do so.
The NUC is getting a lot of use beyond just conferencing since my personal computers are MacBooks and I need a Windows device to connect to some critical AV equipment (Lumagen Radiance Pro video processor, Biamp TesiraForté conferencing DSP, etc.). I’ve also found it very
handy to have a computer permanently connected to my theater AV system because so much movie and performing-arts content has migrated to the internet since the beginning of the pandemic.
The Biamp TesiraForté DSP comes standard with VoIP and analog telephony ports, which made it possible to add a telephone line to my conferencing system. I now often use the Minema effectively as a giant speakerphone.
1) It may not be easy to find integrators with conference-room expertise who are willing to work on a residential project
In 2019, when I was in the design phase for my installation, I found it extremely difficult to hire an integrator with conferencing expertise for a residential project. Hopefully the situation is different today since there are so many more people working from home, but the only way I was able to get a commercial integrator to agree to help me was by tapping some former work contacts. Once the commercial integrator came on board, they collaborated closely with my AV integrator to add the conferencing piece into the overall theater AV system.
These are the key capabilities the commercial integrator brought to the table:
♦ Specifying the conferencing equipment (audio DSP, camera, microphone, mini-PC)
♦ Providing guidelines for conference-room acoustic performance (easy to surpass with the original theater design specs) and lighting levels
♦ Developing a signal-flow diagram for the conferencing system
♦ Programming the audio DSP
♦ “Tuning” the beamforming ceiling microphone
2) Typical commercial conference-room equipment specs may not work in a home theater setting
It didn’t take long after installing the conferencing system for me to realize I would need to swap out the NUC that was originally specified. Since the NUC is always on, I could hear its fan noise in the background when I was watching a movie or listening to music. Replacing it with a fanless model that is completely
silent solved that problem. I also needed to tweak the NUC BIOS settings to turn off the front LED, which was visible through the fabric covers on the screen-wall cabinetry.
When I opened the box containing the Shure ceiling microphone, I realized I had another problem because it was bright white, not optimal for mounting behind black acoustically transparent ceiling fabric. Fortunately, Shure makes the same microphone in black, so that was an easy fix.
One minor change that made a big difference was swapping out the Bluetooth keyboard and mouse that were originally provided for a Logitech K830 illuminated living-room keyboard with a built-in trackpad. Using a mouse is simple when you’re sitting at a conference-room table but not so easy from theater seating.
3) A commercial conferencing DSP may not be certified by some popular VoIP service providers
Although I am currently using the Biamp DSP with a Zoom Phone license, this has been challenging to set up since the Biamp isn’t a Zoom Phone-certified device. Biamp has certifications from Cisco, Avaya, ShoreTel, Mitel, and Skype for Business. I can use my Zoom Phone license seamlessly with the Zoom Rooms software, but since this would restrict me to using the VoIP line only when the NUC is selected as my video source, this isn’t an optimal solution either. Using the Biamp with an analog phone line may in some cases therefore be the simplest option for adding teleconferencing.
I was very fortunate that my project was completed in February 2020, immediately before the lockdown. When I was in the planning stages, I couldn’t have anticipated how much we would use the conferencing functionality in the Minema. Now I can’t imagine living without it.
William Erb is a longstanding movie enthusiast, music lover & home AV tinkerer. He has been using his spare time, now that he is semi-retired after a career in banking and biotech, to renovate his new home in Los Angeles with a private cinema and a distributed audio system, both state-of-the art. William became a client of Sam Cavitt’s Paradise Theater in the very early stages of his renovation project. He was lucky enough to get the private cinema completed just before lockdown, and is glad not to need an excuse to stay home to watch movies and listen to music.