Biamp Audia EXPI, Operation Manual

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6
Courtroom A
microphones #1~10
distributed 70V
speaker system
Courtroom B
Courtroom C
microphones #1~10
distributed 70V
speaker system
microphones #1~10
distributed 70V
speaker system
microphones #1~10
distributed 70V
speaker system
4-track
hard-disk
court recorder
4-track
hard-disk
court recorder
4-track
hard-disk
court recorder
4-track
hard-disk
court recorder
Courtroom D
APPLICATIONS
Courthouse with Multiple Courtrooms and Hard-Disk Court Recording
This application demonstrates the use of AUDIA
®
in
a modern courthouse. This is a networked system
using two Audia
FLEX 20x4CM units and two
Audia EXPO 8-Output Expander units (forty inputs,
twenty-four outputs, CobraNet) . An example system
diagram is shown on the next page.
Each courtroom is shown as having ten
microphones. AUDIA inputs accept microphone or
line-level signals equally well, so some inputs could
instead be from sources such as playback of
recorded evidence. Inputs from the four courtrooms
are connected to the two Audia
FLEX units, which are
located in a local equipment closet. Each
Audia
FLEX unit accommodates inputs from two of
the courtrooms, and provides four system outputs.
In this case, one unit provides the outputs necessary
to feed a hearing assistance system in each of the
courtrooms. The other unit is providing the outputs
needed for sound reinforcement. These outputs are
feeding an MCA8050 multi-channel amplifier.
The MCA8050 amplifier has eight channels which
have been bridged in pairs, essentially creating four
channels of 100 watts each. With four TDT100
transformers installed internally, the MCA8050 is
prepared to drive the 70 volt distibuted speaker
system in each of the four courtrooms.
CobraNet and Ethernet from both Audia
FLEX units
are tied together through an Ethernet switch. This
allows sharing of digital audio signals
(CobraNet)
and control data (Ethernet) on a network.
Connected to the same Ethernet switch, and
functioning as part of the same network, are two
Audia
EXPO units. These two Audia EXPO units are physically located in a central computer/recording office. The maximum distance
between any AUDIA unit and an Ethernet switch is 300 feet. Therefore, this system can span up to 600 feet between the equipment closet
and the computer/recording office. Additional Ethernet switches, or even fiber-optics, can further extend distances between units on the
network.
Each Audia
EXPO receives eight channels of digital audio via CobraNet, over a single CAT5 cable. These eight channels of digital audio
are then converted to analog audio, and appear on eight separate output connections. Each Audia EXPO provides the appropriate
channels of audio for two of the four court recording systems. Mixing and processing of these signals (to achieve proper microphone/track
assignment and consistent recording levels) has already be accomplished back at the Audia FLEX units.
Design example: Recording signals are not gated or equalized, but Levelers are employed to ensure consistent levels and intelligibility.
Matrix Mixers used to provide the following input-to-track assignments: Judge & Sidebar (track 1); Witness, Evidence, & Clerk (track 2);
Defense, Prosecution, Podium, & Wireless (track 3); Jury (track 4). Mixing and processing of signals for hearing assistance and sound
reinforcement have also been accomplished within the Audia
FLEX units. These are the same input signals that feed the recorders, but in
this case they are mixed and gated appropriately using Auto Mixers. Levelers are then utilized at these outputs (to provide consistent
output volume) , and equalizers are utilized at the sound reinforcements outputs only (to compensate for courtroom acoustics) .
Various remote control options are available.
Volume 8 , Select 8 , and Volume/Select 8 rotary encoder panels may be used to provide
volume, override, sidebar, and other such functions. A Logic Box would allow individual microphone privacy switches and/or control of
external functions (such as camera presets or speaker relays) . External switches can even be connected to the Audia EXPO logic inputs,
to allow remote selection of courtroom-to-recorder assignments (via CobraNet bundle assignment) .