User guide

10
Stage
microphones #1~16
stage monitor mixes
Auditorium
Backstage
under-balcony speakers
mixing console
left - center - right
main speakers
announcement
microphone
distributed 70V
speaker system
distributed 70V
speaker system
Lobby
emergency
paging
microphone
APPLICATIONS
Theater with Live Mixing Console and Multiple Speaker Zones
This application demonstrates the use of AUDIA in a
live-performance theater. This is a networked
system using one AudiaFLEX 2x8CM unit, three
AudiaEXPI 8-Input Expander units, and two
AudiaEXPO 8-Output Expander units (twenty-six
inputs, twenty-four outputs, CobraNet). An example
system diagram is shown on the back page.
Sixteen stage microphones are connected to the
inputs of two AudiaEXPI units, which are located
backstage. These sixteen signals then appear at the
outputs of two AudiaEXPO units, which are located
near the mixing console. The console is used to mix
these signals (plus any local source signals, such as
effects and playback) to as many as eight different
outputs: Left/Center/Right (front-of-house), Under-
Balcony (rear-of-house), Stage Monitors (1 & 2),
Lobby, and Backstage. These outputs are
connected to a another AudiaEXPI unit, which is
located near the mixing console. These eight signals
then appear backstage at an AudiaFLEX unit, which
provides signal processing for each of the outputs
before feeding MCA8050 and MCA8150 power
amplifiers located in the same equipment rack.
The MCA8050 amplifier has eight channels bridged
in pairs, creating four channels of 100 watts each.
These outputs are driving the Backstage, Lobby, and
Monitor speaker systems. The MCA8150 amplifier
also has eight channels which have been bridged in
pairs, providing four channels of 300 watts each.
These outputs are driving the Left/Center/Right and
Under-Balcony speakers. TDT300 and TDT100
transformers are installed internally for outputs
driving 70V distributed speaker systems.
The AudiaFLEX unit also receives input from an emergency paging microphone (located in the office), and from an announcement
microphone (located backstage). These two signals can be routed (with override capability) to any of the eight outputs. Example:
Emergency paging may be desired at all outputs, while announcements may be routed to the Lobby or Backstage as necessary. CobraNet
from the six AUDIA units is tied together through an Ethernet switch. This allows sharing of digital audio signals on a network. 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 stage and mixing position. Additional Ethernet switches, or even fiber-optics, can be used to further extend distances between units on
the network. An added benefit to CobraNet is that it affords the necessary isolation to help avoid ground loops between active components
in different locations. CobraNet also saves on the labor and expense of wiring, by transmitting eight channels of digital audio over a single
CAT5 cable.
Of course, all live mixing is done at the console. The AUDIA network provides transportation, routing, and processing of the signals.
AudiaEXPI and AudiaEXPO units act as a 'digital snake', transmitting digital audio between the stage and mixing position. The AudiaFLEX
unit provides routing and remote control capabilites, as well as signal processing for the speaker outputs. In the system design, the
emergency and announcement microphone inputs employ Levelers (for consistent volume), Routers (for output assignment), and Duckers
(for page-override). At the outputs, processing includes Equalizers (to compensate for acoustics), Comp/Limiters (to control peaks), and
Delays (for speaker zone alignment).
Various remote control options are available. Volume 8, Select 8, and Volume/Select 8 rotary encoder panels may be used to provide
volume, preset selection, and even page routing functions. A Logic Box allows system control via external switches, or control of external
equipment from the system.