The Warwick Manufacturing Group (WMG) just completed construction of a $70 million research facility at the University of Warwick in Coventry, England that is outfitted with high-end audio/visual system technology.
Two of the rooms in the building, a 100-seat auditorium and a psychoacoustics research laboratory, required high-fidelity audio with a capacity for extremely flexible routing and a customized user interface. WMG hired UK-based Pure AV Ltd. to realize their very specialized needs, and Pure AV support engineer Colin Hasted designed their audio systems around Symetrix SymNet open-architecture DSP solutions.
The 100-seat auditorium serves as the collective meeting place for all of WMG’s researchers and students. Because of the highly technical nature of their work, it features a networked AV system with sophisticated audio fidelity and visual clarity.
On the input side are DVI and VGA input plates, CD, DVD, resident PC, pre-recorded content from a remote server, and an access grid that feeds in distributed television content. Fourteen channels of microphones feed the system, from Shure lectern mics, to Sennheiser presentation mics, to eight suspended Audio Technica ceiling mics.
In addition, surround sound processing from a Denon DN-A7100 preamp feeds the SymNet DSP system, rather than the other way around. That arrangement enabled Hasted to have full speaker management control of the entire auditorium system and to provide complete flexibility to mix microphones and video conferencing with program material.
“SymNet manages all of the audio and sends it out appropriately so that we can easily deliver monaural, stereo, or 5.1 sources without using different sets of speakers,” said Hasted.
At the system’s core are two SymNet 8×8 DSP units and one SymNet BreakIn12 for 28 inputs and 16 outputs.
Box “A” handles all of the echo cancellation for the room’s many microphones and routing.
Box “B” handles all of the loudspeaker management for the 5.1 Ohm BR series loudspeakers. Each loudspeaker has dedicated EQ, filters, compression, and limiting (for protection from overzealous operators). The two units fuse seamlessly into one via SymLink.
“We went with SymNet, first, because it has better signal-path fidelity than the other units we compared it to and second, because it has ample processing power to deliver everything WMG asked for and the flexibility to create a customized user interface,” said Hasted.
“We did direct, on the bench comparisons between SymNet and its competitors, and found SymNet to have the most transparent signal path. That was critical for the auditorium and paramount for the psychoacoustics laboratory. Stunning echo cancellation and full loudspeaker management was also important, as was ready and customized control from a 17-inch AMX touch screen.”
Beyond the 5.1 output, the SymNet processors also manage stereo recording feeds to a high-definition broadcast recorder, a feed to the building-wide CAT 6 video distribution network, and a dedicated mix to a Sennheiser IR system. Visually, the room benefits from twin Christie HD6K projectors that, in addition to the usual sources, can draw video from anywhere else in the building.
A Polycom HDX 9004 high-definition video conferencing system links the auditorium with the rest of the world. The SymNet processors deliver a stereo mic mix and a separate content mix to the system and handle noise reduction over calls.
The psychoacoustics laboratory is a unique environment by anyone’s standards. The researchers who use the space are asking how we can engineer acoustic environments, not just with less noise (as research to date has dogmatically assumed that all noise is bad), but also with more subjectively pleasant noise.
To get answers, they must necessarily quantify as rigorously as possible the seemingly unquantifiable quality of “pleasantness” in “soundscapes.”
The researchers use a SoundField MKV microphone system and a portable Edirol R4 Pro recorder to capture environments in the field in true three-dimensional sound using SoundField’s innovative capsule technology. Back at the laboratory, they either use the captured material as-is, or perform proprietary processing to “improve” or “degrade” the sound for the purpose of better understanding what makes some environments pleasant and some environments unpleasant.
The three-dimensional audio is decoded via SoundField software running on Nuendo and presented to a SymNet 8×8 DSP and two BreakIn12s. Additional inputs include a Denon DN-A7100 capable of delivering 7.1 or 5.1 surround sound and a solid-state video and audio player for reproduction of stereo or binaural sound clips with video on demand.
Via an AMX touch screen and a SymNet BreakOut12, the SymNet 8×8 DSP elegantly maps any of those inputs in any format (full 16-channel 3D, 7.1, 5.1, stereo, binaural, monaural) to two circles of eight KEF reference loudspeakers and/or headphones.
The system makes tremendous use of SymNet’s capacity for intelligent routing of complex signal paths, while distilling that complexity to something that’s simple from a user’s viewpoint. Remaining outputs feed a stereo video recorder and send audio to the building’s network.
“Again, SymNet controls the system with the utmost fidelity,” said Hasted. “For what they’re doing in the lab, truth in the signal path is essential.” Those presented with the audio for testing use small wireless touch panels to both record their responses and control their virtual environments.”