Brian - thank you for your kind note. I realize that there are on ton of subtle details in this diagrams that we have learned from experience.
Here are some less obvious concepts.
1. Any time an HDMI splitter is used it could be for one of three reasons
a. we need to replicated one signal to multiple places. An example is on page 4 where we use two different splitters. One for the dual displays on the stand behind the privacy screen. A second for the video sources on the stand that send a HDMI signal to the HDMI input jack on the podium as well as to the projector on the stand.
b. when we have a HDMI signal quality issue, where the HDMI signal needs to be regenerated, before feeding a secondary input source. For example one of the video cameras when fed to the ATEM switcher flickers. The splitter cleans up the signal and makes it more stable.
c. a third case is where we are trying to get the HDMI protocol negotiation to use a higher resolution protocol. For example the HDMI output of the ATEM if directly connected to the building EXTRON video switch negotiates a lower resolution standard. If we use a splitter that has port 1 connected to a monitor and a second port connected to the Building Extron switch, then the ATEM uses the resolution of the attached monitor and then uses the same resolution for the building feed.
2. We are limited by what the AV system supports. At its heart the building system is a single channel AV video distribution system. There is a second distribution system in our buildings that goes everywhere, Ethernet. We use that Ethernet backbone for two additional purposes.
a. Second video distribution system. Using the NDI protocol we can send video from a computer to a video decoder. The NDI decoder is an Apple TV with some software loaded on it. The encoder is usually OBS studio. This allows us to send a video presentation or PPT presentation from the back room to the projector in the chapel. When the presentation is over the screen goes black. If we were to use the main video feed the projector would display the camera views during the rest of the meeting or someone would need to go to the front to turn the projector off and on.
b. Audio distribution system. There are lots of digital audio protocols over Ethernet. One protocol is Dante' a second protocol is AVB (Audio Video Bus). Since the building is wired with Gigabit Ethernet we are using that existing cabling to route audio. In the block diagram you see three Tesira Forte AVB VI processors. These audio processors can be programmed as a single system using Ethernet as a communication buss between them. This let's me have Interpreters in the Children's meeting room, transmitters for the various languages in a central location, and a third processor in the AV room to inject audio into the building sound system. No need to pull special audio cables to pull different parts of the building together.
3. The Listen LT-800-72 is one of the standard assisted listening transmitters used by the church. Unlike the Williams transmitter this device has a built in mixer as well as an audio output.
We use the audio output of the main chapel ALS transmitter to feed audio to an audio processor which then routes audio to a second audio processor located with the interpreters in the Children's Meeting Room. That second audio processor then feeds a simple Williams transmitter to give the interpreters a clean audio feed of the podium audio.
We use four other LT-800-72 transmitters to transmit the various languages throughout the meetinghouse. Channel one is the interpreter audio feed. Channel two is audio from the collocated computer. The transmitter can mix those two audio sources natively. The computer performs three roles. The first is, via OBS studio, to loop an audio track identifying the channel. This helps users select on their receivers the language they would like to listen to. Secondly the computers can play back pre-recorded broadcasts from church headquarters. The playback is synchronized via Bitfocus Companion and played back using OBS studio. The third computer use is as the interpreter stream into Zoom.
Hopefully this helps you better understand the plan. This has evolved over many years. You can see that we have tried many different options from all the revisions posted on our website. Many of our current design decisions are based on learnings and sometimes failures from previous sessions. There are many ways to accomplish this work. I am just sharing what works for us.
All the best,
Dave Swartz
STS Federal Way Washington Stake
. So even though our stake could use improvements for our translation (only Spanish for now), all I can do is pass it along and let them decide.