Technology Help - Hybrid Meetings

Chorleywood u3a

This is a document by Mike Field detailing how Chorleywood u3a set-up and run their hybrid meetings without the risk of feedback.

Overview

We are lucky in that the Chorleywood Parish Council listens to me when I specify equipment, and have over the last 10 years fitted the Memorial Hall (200 seater + plus stage) with a full sound system which includes four radio mics (either head-mics or handheld - speakers choice) with two receivers for the four mics mounted on the stage and at the back of the hall. The receivers both feed into the mixer - one per channel.

The hall also has a 5000 lumen full HD projector mounted on the ceiling onto a 16 foot wide electric screen. Inputs for the projector are via HDMI cables from either the stage or the rear of the hall.

The sound system can also be controlled from either from the stage or rear of the hall.

Chorleywood was the first town/village in the UK to be fully cabled for broadband back in 1986 so the internet connection in the hall is 66Mbit/s (fibre to the premises) and should be updated to 150Mbit/s shortly by BT. Most people in the village use Virginmedia as it offer up to 500Mbit/s.

This makes it somewhat easier to run hybrid meetings as most of the equipment is permanently installed!

The reason the Parish Council listen to me is that before the equipment was installed (in stages) they were losing about £10k per year on the halls as no-one wanted to book it. Now there is a waiting list and it makes about £15k per year profit allowing them to upgrade the decor, seating as well as the AV facilities.

Zoom Hybrid Meeting Operational Notes

Equipment List

Mixer: ​Behringer 1222USB mixer £160.99 (Amazon) (8 mic + 4 stereo line inputs + usb in/out port)
​or ​Behringer 1204USB mixer £123.00 (Amazon) (4 mic + 2 stereo line inputs + usb in/out port)

Camera​​: Tenveo Video Conference Camera 20X Optical Zoom Full HD 1080p USB PTZ Camera for Business Meetings (TEVO-NV20U) £ 399.00 (currently out of stock)

Laptop​: HP Omen 15 Laptop (Useful in that it has a 4-channel wifi giving a gigabit connection without having to run a cable.)

Sound

All microphones and other sound sources go through the mixer with the output to the hall amplifier and speakers and hearing loop volume controlled by the Main Output slider.

Chorleywood use:

• four or five radio mics - speaker, chair, wander mics for questions, and a mic for the second computer user to ask questions on behalf of zoom viewers

• Other sound sources e.g. music or live artists.

The USB port on the mixer connects to a USB port on the laptop – no other connections for sound are required or are allowed.

The volume is controlled by the individual input sliders and once set in advance should NOT be adjusted again – the local hall volume is controlled by the mixer’s main output.

(Mixer practice is to adjust the individual inputs slider to 10 on the slider then adjust the small preset gain control to just below the point where the Gain light starts to flicker. Do this for each input in use and then press the Mute button for each slider. The output will then be correct for the usb port’s output.)

Laptop Connection

HDMI connects to the projector. (up to 50m will work without amplification – 35m is better)
USB2 cable connection to the mixer USB port
USB3 cable connection to the conference camera
USB2/3 port for the wireless mouse transmitter receiver
USB2 connection for presenter slide control

Camera

The camera is mounted on a tripod at the rear of the hall and has a 20x optical zoom and connects to the laptop via a USB3 cable. It is controlled via an infra-red remote control allowing control over the optical zoom, pan (up and down), rotation +/- 170ᵒ left and right, auto/manual focus and colour balance. The camera has full HD definition. The camera also has its own power supply via a power bank charging ‘brick’.

Notes:

1. Using the USB port on the mixer removes the problem of feedback from remote users as the USB mixer port both supplies the sound from the meeting hall microphones (or other sound sources) to the zoom computer AND returns the sound from the remote users. This allows the zoom programme to mute the hall mics etc. when the sound is coming from the remote Zoom users hence no feedback.

2. Use a second laptop (with its sound muted and a pair of headphones to check the sound from the meeting) set up as co-host to look after controlling the waiting room users and to ensure the remote zoom users have their sound turned ‘locked’ off by the co-host. The sound lock-out is to prevent late arrivals from unmuting themselves and putting background chatter and noise to the other zoom users – cannot get to the Hall as that is controlled via the mixer and remains muted there

3. The second laptop also allows you to see what the remote zoom users see – it is different from the main host computer.

Sound System Setup Photo Guidance for Memorial Hall users
(click on individual images to enlarge) :-

Sound System Setup 01

Sound System Setup 02

Sound System Setup 03

Sound System Setup 04

Sound System Setup 05

Sound System Setup 06

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Mike Field
Chorleywood U3A