Manual

Issue 3, August 2018 Model 44D User Guide
Page 16 Studio Technologies, Inc.
Full bandwidth audio signals will past
through the Model 44D’s line inputs and
line outputs.
When SW3 is in its on (up) position the
low-pass filters will be enabled. Enabling
the low-pass filters can improve the per-
formance and possibly the intelligibility of
audio signals that consist mainly of voice
content. In this case audio content in the
extend high-frequency range will typi-
cally provide little enhancement to system
performance and can often contain extra-
neous nose or other unwanted artifacts.
Also, in situations where a Model 44D’s
GPO functions are used, enabling the
low-pass filters will prevent the signaling
tones (typically 20 kHz) from being part of
the signals that are presented on the line
outputs.
Operating Mode
Switch SW4 is used to configure the
Model 44D’s operating mode. When SW4
is in its off (down) position the Model 44D
functions as an audio interface. This would
be considered its normal mode of opera-
tion. When SW4 is in its on (up) position
the tone generator mode is selected. In
the tone generator mode the Model 44D
generates 18 kHz and 20 kHz sine-wave
tones. Analog output 1 and Dante trans-
mitter (output) channel 1 will have a con-
tinuous source of 18 kHz present. Analog
output 2 and Dante transmitter (output)
channel 2 will have a continue source of
20 kHz present.
Dante Configuration
To integrate the Model 44D into an audio
interface application several Dante-
related parameters can be configured. At
a minimum, signals must be routed to the
two Dante input (receiver) channels and
from the two output (transmitter) channels.
The configuration settings will be stored
in non-volatile memory within the Model
44D’s circuitry. As such, power-down and
power-up activities will not impact the
unit’s settings. The Model 44D uses the
Ultimo 2-input/2-output integrated circuit
to implement the Dante architecture.
The two Dante receiver channels will be
assigned to the desired Dante transmitter
channels on other devices. The two trans-
mitter channels associated with the Model
44D’s Dante interface must be assigned
to the desired destinations (Dante receiver
channels on associated devices). This will
typically be done with the Dante Controller
software application which is available for
download free of charge at www.audinate.
com. Versions are available to support
Windows® and OS X® operating systems.
Within Dante Controller a “subscription” is
the term used for routing a transmitter flow
(a group of output channels) to a receiver
flow (a group of input channels). Note that
as of the writing of this guide the Ultimo
SW4 – Operating Mode
1 2 3
4
ON
1 2 3
4
ON
Tone Generator
Audio Interface
Figure 7. Operating mode configuration switch
Enabled
Disabled
SW3 – 10 kHz Low-Pass Filter
1 2 3
4
ON
1 2 3
4
ON
Figure 6. 10 kHz low-pass filter configuration
switch