Studio Technologies 212 2013 - Manual (Page 13)

Model 212 User Guide Issue 5, May 2013
Studio Technologies, Inc. Page 13
Optional Balanced Digital
Audio Output
Circuitry contained within the Model 212
allows a technician to add support for an
AES3 balanced digital audio output. This
type of interface allows two channels of
digital audio to be carried over a balanced
110 ohm circuit. In some Model 212 ap-
plications the AES3 output will be imple-
mented using a 3-pin male XLR connector
installed in the back panel. Other applica-
tions may use a multi-pin connector, such
as the Neutrik® EtherCon® version of the
8-pin RJ45 jack.
The signal coming out of the AES3 out-
put will be identical to that coming out the
Model 212’s AES3id output. The same
content will be transmitted at the same
bit depth and clock rate. For full isolation
separate circuitry, including a matching
transformer, is provided for each of the
two outputs.
Unbalanced Digital Audio
Input
The AES3id input can be used to connect
unbalanced digital audio signals to the
Model 212. The two audio channels associ-
ated with the interface can serve as sourc-
es for the stereo headphone output. The
input, physically a BNC connector located
on the Model 212’s back panel, allows a
depth of up to 24 bits to be supported;
however, anything in the range of 16 to 24
bits will work correctly. The input is “self-
clocking” so that compatibility with virtually
any AES3id source should be possible. It’s
expected that in most cases the Model 212
will be used in professional audio environ-
ments where the sample rate will be 48
kHz. However, any source with a sample
rate from 32 to 96 kHz will work correctly.
For the AES3id input to be active a configu-
ration setting must be correctly made. This
topic is discussed in detail in the configu-
ration section of this user guide. It’s also
important to note that the selected digital
input source will also serve as the clock
source for the Model 212’s digital outputs.
Optional Balanced Digital
Audio Input
Circuitry contained within the Model 212
allows a technician to add support for an
AES3 balanced digital audio input. This
type of interface allows two channels of
digital audio to be received over a bal-
anced, transformer-coupled, 110 ohm
circuit. In some Model 212 applications
the AES3 input will be implemented using
a 3-pin female XLR connector installed in
the back panel. Other applications may use
a multi-pin connector, such as the Neutrik
EtherCon version of the 8-pin RJ45 jack.
As with the AES3id input, for the AES3 in-
put to be active the appropriate configura-
tion DIP switches must be set. And as with
the AES3id input, in additional to providing
audio sources for the stereo headphone
output, the AES3 input will also serve as
the clock source for the Model 212’s digital
outputs.
Bidirectional Digital Audio
Interface
The Model 212 includes a bidirectional
digital interface for use in special applica-
tions. Using a single 75 ohm, unbalanced
connection, two channels of digital audio
can be both sent and received. The two
channels of receive audio can be used
as cue sources for the stereo headphone
output. Bit depths of up to 24 and sample
rates of 32 to 96 kHz are supported. For