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COVENTRY, ENGLAND - MARCH 2009: The Warwick Manufacturing Group (WMG) just
completed construction of a $70 million research facility at the University of Warwick in Coventry, England that redefines the state-of-the-art in
audio/visual technology, cross-discipline exchange, and academia-industry knowledge transfer. 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 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 audio fidelity and visual
clarity that would put most high-end cinemas to shame. 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 8x8 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 speakers. 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 8x8 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 8x8 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.
