Large Auditorium Audio and Video Distribution

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This system design template describes how Tesira products can provide audio and 4K video distribution over a single network for a large auditorium. The system design assumes a large auditorium of greater than 2000 seats. The template contains audio and video distribution for the front of house, back of house, lobby and box office. In the past, performing arts spaces have generally been designed with disparate systems for audio and video. TesiraLUX, Tesira SERVER-IO, and Tesira AMP amplifiers running on AVB allow for a single system design, with all audio and video signals automatically kept in sync without any manual intervention required.

This template serves as a guide for a complex system that spans an entire building. It can easily be expanded to add automatic unattended mode, assisted listening systems, orchestra pit, paging, intercoms, network redundancy, additional cast and crew facilities, balconies, overflow or breakout function spaces, among many other possibilities.

Auditorium design

Converged networked audio and video distribution
Options for compressed or uncompressed video transport, up to 4K resolution
Front of house and stage manager positions
Main loudspeaker left and right arrays
Auditorium delay ring
70V audio distribution for back of house, lobby areas and restroom areas
Microphone inputs via a Dante console
Stage monitors
Confidence displays and audio monitors at front of house position
Cameras for recording and Image Magnification (IMAG)
Two side projectors and one large main rear projector
Lectern with video inputs
Two side projectors and one main rear projector
Displays in the lobby and back of house
Media players, signage players and video sources
Recording and streaming
Stage aux video inputs and outputs
Emergency alarm system mute interrupt and reset

Equipment list

1 - Tesira SERVER-IO Cards: 1x SNC-1, 2x DSP-2, 1x AVB-1, 1x DAN-1, 1x SOC-1
2 - TesiraXEL 1200.2 Four channels, 2400W total output, daisy chain AVB ports (main arrays/subwoofers)
2 - TesiraXEL 1200.1 Four channels, 1200W total output, daisy chain AVB ports (stage monitors/delay speakers)
1 - AMP-450P 4-CH PoE+ amplifier providing 4x 50 Watts burst power (lobby/box office)
15 - TesiraLUX IDH-1 Video encoder connected 10G
20 - TesiraLUX OH-1 Video decoder connected 10G
2 - Community IP8-1152 High Power 15-inch Two-Way Installation Loudspeaker; Power Handling: 800W continuous (beamwidth per application)
2 - Community IS8-115 High Power 15-inch Subwoofer, 360°H x 180°V; Power Handling: 1000W continuous
8 - Community IC6-1062 High Output 6.5-inch Two-Way Installation Loudspeaker, 100°H x 100°V, 70/100VTaps(T models); 150W continuous (delay ring)
4 - Community MX10 10-inch Compact Coaxial Two-Way Monitor; Power Handling; 200W continuous (stage monitors)
8 - Community D6 Two-way, full-range, coaxial ceiling loudspeaker, 8 ohm or 70V/100V operation; 100W continuous, (quantity as required)

Example configuration file

The example template contains one audio partition and one 10G video partition. The file will require presets or control interfaces to change video and matrix mixer routing. Microphone left-right mixes and stage monitor feeds are received through the 6 channel Dante Input block. The embedded HDMI audio and stage auxiliary audio is also received in to the mixer block through partition connectors. The mix of inputs can be independently delivered to the front array, delay ring, stage monitors, lobby, back of house, front of house monitors and the recording mix. There is a fire alarm logic input to trigger a global mute of the matrix mixer via a preset. A logic output can power a LED to show the alarm state and include a reset button to restore audio.

The 10G video partition has all input and outputs connected to a single AV Router. Partition connectors are used to de-embed the HDMI audio to the audio partition. Audio mixes are returned to the video partition and re-embedded using the AV Combiner blocks. The analog aux audio is used to deliver stage auxiliary inputs and the front of house audio monitors.

To assist with deployment and commissioning of systems which include Community speakers, a Tesira Library File (.tlf) has been created. This includes custom blocks with Biamp's recommended EQ curves to optimize the sound the included loudspeakers in this design. The custom blocks have been included in this system design template file. These blocks can also be found in the Processing Library in Tesira software.

Download Configuration File: Large Auditorium.zip

Network details

The network can make use of converged control, AVB and Dante protocols running on shared network fabric to reduce the amount of switch hardware required. TesiraLUX supports 1G or 10G networking. AVB is able to seamlessly mix different port speeds. TesiraLUX will use 10G in this example for lowest possible latency with best video quality. The network will combine one 48-port 1000BASE-T copper switch and one 48-port 10GBASE-SR fiber switch uplinked together. Reference the Video Network Design Guide for information on building a high capcity AVB video network. See the List of AVB-capable Ethernet switches for compliant switch models.TesiraXEL offers the ability to daisy chain the network ports, use single cable mode per amplifier, or use redundant AVB ports for signal path resilience.

Setup Requirements:

48-port 1G AVB enabled switch
SERVER-IO DSP, AVB networked amps, Dante devices and control ports will be on the 1G switch
48-port 10G SPF+ AVB enabled switch
TesiraLUX video end points will be on the 10G fiber switch
1G uplink between switches
Enable AVB on the switches
Configure VLANs for Dante and Control (AVB automatically VLANs.)
Configure management IP addresses and DHCP

Audio setup

The main left and right arrays for auditorium sound reinforcement have a combined total of 4800W of power available from the networked amplifiers. The example in the template assumes a pair of bi-amped cabinets for each array with powered sub cabinets all configured in stereo. This is only one example of many other possible clustered designs that would best suit the particular acoustic space.

Custom blocks with Biamp's recommended EQ curves to optimize the sound of the included loudspeakers in this design have been included in the attached configuration file.

Level adjustments and peak limiter values are applied before the signals are delivered to the networked amplifiers. The Tesira AMPs contain hardware limiters but the Peak Limiter DSP block allows for fine grained control. The 16 band PEQ before the custom blocks is used for room coloring.

Tesira Software automatically handles synchronizing outputs during compilation using delay EQ groups. Dynamic delay EQ is used on the HDMI audio paths so the media remains time aligned with any changes in video processing. Delay EQ may also be used to synchronize all audio and video outputs if the system designer desires. See the Lip Sync and Delay Equalization in TesiraLUX article for further audio-video sync information. Different delay EQ groups can be configured for audiovisual isolated spaces. The delay ring in the auditorium requires the appropriate delay time value for the acoustic space. The loudspeakers in the lobby and back of house may also have delay applied to align with the main auditorium or displays located outside. Lobby and Back of house speaker zones support two speakers on each run in this configuration. Based on design needs for specific applications, additional AMP-450P, or 70V capable amplifiers may be required if additional speakers are needed in the space.

HDMI audio will require adjustment during commissioning. Testing should include various types of user created and consumer media. The dynamic range can vary on different content types. Level controls, AGC and peak limiters can be used to compensate for large changes in the audio dynamic range of HDMI content.

Video setup

TesiraLUX supports 1G or 10G network connections for video streaming. In this example, all of the TesiraLUX video end points are configured for 10G fiber connection. The bandwidth mode is configured to 2160p60 with no compression. Scaling and compression are disabled to achieve end-to-end transit latencies near 16 ms, a critical factor for synchronization with live audio and image magnification. No compression allows large projected images to appear in maximum detail for the audience. See Video Bandwidth Controls in TesiraLUX and Video and Network Latency for more information.

HDMI audio de-embedded via the network and mixed on the DSP. HDMI audio can be mixed with mic audio and returned ot the HDMI outputs to recording or streaming services. Dynamic Delay EQ within Tesira will preserve the audio-video time alignment throughout all of the DSP and video processing. Delay EQ can be used to time align signals from the networked amplifiers and the HDMI outputs if desired by the system designer.

EDID typically does not require any intervention and the EDID Preferred mode is sufficient. Each TesiraLUX end-point contains a broadcast quality scaler. EDID is managed automatically by each discrete end point.

Control

A large system expects that multiple users may be manipulating audio and video controls at the same time. Tesira can be controlled via an external touch screen system, software interface and through a series of recalled presets. Presets may contain blocks from both audio and video partitions. Presets and the instance tags of block objects are addressable by external systems through serial or IP communication. Tesira Canvas software can be used to connect meters, adjust levels or recall presets for the AV Router.

The fire alarm system mute can be connected to the GPIO ports of the SERVER-IO or TesiraLUX devices. GPIO can provide LED status indicators and an alarm reset switch. Logic is extendable to include an automatic operation mode, auto input port selection on the lectern or activation of standby mode for amplifiers, among a wide range of possibilities.