7
The CUE/SOURCE, CR, STUDIO, and HDPN controls are also rotary
encoders used primarily to control the level of the four dedicated monitor
outputs on the Engine. The two Monitor OLED displays show the current
levels for those four outputs and their status (a red X over a bar graph
icon indicates that output is muted).
The CUE/SOURCE and STUDIO encoders are also used to select and take
“wild sources” for the CR and Studio as well as assign a source to the
different EXT, EXT 1, and EXT 2 buttons.
The Surface controls are all on a single field-replaceable Control Panel
that connects to an internal network interface board using one (DMX-8) or
two (DMX-16) plug-in ribbon cables. This allows for rapid field
replacement, with minimal interruption to operations, in case of spills or
other damage to the Surface controls since the program audio is in the
Engine rather than the Surface (except for the audio to the side panel
headphone jack).
Meter Bridge
The integrated direct-view Meter Bridge (Figure 1-4) sits above and
behind the control panel. It has three stereo level meters, a Timer, and an
On Air indicator. The left meter displays the Program 1 bus levels. The
middle meter displays the Program 2 bus levels. The right meter is
switchable between showing the other two program buses (PGM 3 or PGM
4) or an External signal (EXT) like an off-air tuner signal. The switched
meter can also be set to auto-switch to show cue levels while cue is active.
The meters normally show both the average and peak levels, but
software settings allow them to be changed to show only the average level
or only the peak levels.
Figure 1-4 DMX Meter Bridge
The four-digit Timer is controlled manually, using the Monitor section
S/S button (Timer Start/Stop control), or automatically, when the Auto
Timer button is lit and an audio source, set for Timer Reset (assigned to
specific audio signals in the Surface Setup app), is turned on.
DMX Engine
All audio and logic connections are made on the rear of the DMX-16
Engine (Figure 1-5). This 1RU device has a 5-port Gigabit switch; two
high-quality low-noise Mic Preamps (with gain control and 48-volt
phantom powering); Signal Processing with EQ and dynamics (applied
on a fader channel basis); eight routable audio inputs (four analog and
four AES); four Program audio outputs (four analog and four AES
outputting the same set of signals); four dedicated analog outputs (to
feed powered Control Room and Studio monitors, powered cue speakers,
and an outboard board operator headphone amp); six GPIO logic
contacts (each independently set to function as a logic input or logic
output) and an Ethernet jack to connect the Engine to the built-in Gigabit
switch.
Figure 1-5 DMX-16 Engine, rear panel
Input and Output Connectors
All audio, logic, and network connections on the Engine, other than the
two mic inputs which have female XLR connectors, use RJ45 connectors
and CAT5e or CAT6 wiring. The analog and AES audio wiring conform to
the StudioHub+ wiring convention (with two balanced analog or one stereo
AES signal on each RJ45 connector) using CAT5 cabling. The RJ45 LOGIC
connector, which has six logic contacts along with +5V and GND, is wired
per the WheatNet-IP logic convention. Figure 2-4 (page 12) has pin out
tables for the RJ45 connectors used for audio and logic.
DMX SPECIFICATIONS
Test Conditions:
FSD = Full Scale Digital, 0 dB FSD equivalent to +24 dBu analog
0 dBu corresponds to 0.775 volts RMS—regardless of the circuit
impedance, as measured using a 600 ohm circuit.
Noise specs measured using a 22 Hz – 20 kHz bandwidth. A 30k Hz
bandwidth increases the noise measurement by 1.7 dB.
Mic Preamp
Source Impedance: 150 – 600 Ω, balanced
Nominal Input Level: -50 dBu
Input Range: -70 to -31 dBu (using trim control to reach nominal level)
Equivalent Input Noise: -131 dBu
Logic GPIO
Six per RJ45 connector: Connection assignments made using PR&E
Navigator (logic input or output; the type of logic command)
Logic Inputs: Current-limited using internal pull-up. Supports +5 to +12
volt logic. For a logic low, input voltage must fall below +2.5 volts.
Logic Output: +5 to +24 VDC logic, 50 mA nominal, 100 mA max
