AV-over-IP for Meeting Rooms & Lecture Theatres: Irish Design Guide

The Death of the Matrix Switcher

For thirty years, the matrix switcher defined AV system architecture in Irish corporate, education and hospitality buildings. A matrix switcher is a dedicated hardware unit with a fixed number of HDMI or HD-SDI inputs and outputs — a 16x16 matrix can route any of 16 input sources to any of 16 output displays, under control of a central processor or touch panel. Matrix switchers were expensive (EUR5,000-50,000+ per unit), inflexible (adding an input or output required hardware replacement or upgrade), required dedicated cabling infrastructure separate from the ICT network, and were becoming maintenance headaches as proprietary hardware aged and components became unavailable.

AV-over-IP replaces the matrix switcher with an IP-networked system of encoder and decoder units. Each source (laptop, camera, media player) connects to an encoder that converts the video/audio signal to an IP stream. Each display connects to a decoder that receives an IP stream and converts it back to HDMI/DisplayPort for the screen. Routing — which encoder's stream goes to which decoder — is controlled by a software matrix running on a server or cloud platform. Adding a new source or display requires only adding a new encoder or decoder to the network — no hardware core upgrade required. And because the AV network is a standard IP network, it can share infrastructure with the ICT, CCTV and BMS networks under the converged building network model.

AV-over-IP Protocol Comparison

Network Infrastructure for AV-over-IP

The most common failure mode on Irish AV-over-IP projects is specifying the AV system without first designing and validating the network infrastructure. AV-over-IP has strict network requirements that differ from standard ICT traffic and must be designed before any AV hardware is selected:

• Dedicated AV VLAN: AV traffic must be isolated from ICT user traffic to prevent broadcast storms, bandwidth competition, and security incidents. A dedicated VLAN with QoS marking (DSCP AF41) is mandatory.
• IGMP snooping enabled: AV-over-IP systems use IP multicast for one-to-many distribution (one encoder to multiple decoders). IGMP snooping must be enabled on all switches in the AV VLAN to prevent multicast flooding to all ports.
• PTP (IEEE 1588) for Dante audio: Dante audio distribution requires sub-millisecond synchronisation across all devices, achieved by Precision Time Protocol (PTP) boundary clocks or transparent clocks in every switch in the Dante VLAN. Standard NTP (1-10ms accuracy) is insufficient for Dante.
• Bandwidth headroom: For NDI, calculate total simultaneous streams multiplied by 200Mbps per stream, add 50% headroom, and ensure all uplinks and core switches can support the resulting load. A 20-room meeting floor with 40 NDI streams requires 8Gbps aggregate bandwidth — a 10GbE core switch is the minimum.

Microsoft Teams Rooms: The Irish Corporate Standard

Microsoft Teams Rooms (MTR) has become the de facto standard for Irish corporate meeting room AV, driven by the dominance of Microsoft 365 in Irish enterprise (particularly in the financial services, pharmaceutical and professional services sectors that anchor the Dublin commercial office market). MTR certified systems are validated by Microsoft to deliver the full Teams meeting experience:

Irish University Lecture Theatre AV Design

Irish universities — Trinity College Dublin, University College Dublin, University of Galway, University of Limerick, DCU and Cork's UCC — are in an active cycle of lecture theatre AV modernisation driven by the hybrid teaching model that emerged post-pandemic. A modern Irish lecture theatre AV system specification includes: laser projector (5000+ lumens for ambient light rejection in large theatres, 4K resolution for detail in code/engineering content); camera tracking system (PTZ cameras with automatic presenter tracking — Panasonic AW-UE150, Sony SRG series — or ceiling-mounted tracking systems like Vaddio EasyIP Decoder); lecture capture system (Panopto or Echo360 — both have significant Irish university market presence, recording presenter camera and screen capture simultaneously); hearing loop system (BS 8300 compliant, hearing loop perimeter for users of hearing aids with telecoil, teleloop amplifier in AV rack); and room booking integration (Timetable software — Scientia Resource25 or Asure Software — displaying room schedule on external panel). Acoustic design is critical for Irish lecture theatres: CIBSE TM57 recommends RT60 of 0.6-0.8 seconds for speech intelligibility in lecture spaces, requiring acoustic treatment of the rear wall and ceiling and careful assessment of hard surface reflections from digital displays.

Acoustic Requirements: RT60 and STI for Irish AV Rooms

AV-over-IP delivers perfect audio signal transmission — but perfect signal is wasted if the room acoustic is poor. Irish ICT and AV designers must ensure acoustic requirements are coordinated with the architect and interior designer at design stage:

• Meeting rooms (up to 12 people): RT60 target 0.4-0.6 seconds, minimum STI (Speech Transmission Index) 0.75. Achieved by: acoustic ceiling tiles (NRC 0.7+), carpet or acoustic flooring, soft wall treatments, and meeting room sound masking (Biamp Tesira, Cambridge Sound Management).
• Boardrooms and large meeting rooms: RT60 target 0.5-0.7 seconds, minimum STI 0.70. Premium Irish boardrooms often specify proprietary ceiling acoustic systems (Armstrong, Knauf) and dedicated sound masking infrastructure.
• Lecture theatres (university and education): RT60 target 0.6-0.8 seconds for speech, 0.8-1.0 seconds for music performance spaces. CIBSE TM57 acoustic design guidance applies.
• Hearing loop: BS 8300 (Design of buildings and their approaches to meet the needs of disabled people) requires hearing loops in all meeting rooms accommodating more than 10 people in Irish buildings subject to the Disability Act 2005.

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