Studio Technologies 76D 2014 - Manual (Page 22)

Issue 11, May 2014 Model 76D/77 User Guide
Page 22 Studio Technologies, Inc.
for Surround
Remote Dim
Two configuration choices are associated
with the remote dim function: disabled and
enabled. To utilize the remote dim function
simply configure it for enabled.
Input Delay
A time delay can be added to the input
signals, allowing compensation for delays
that may be present on associated video
signals. The time delay applies to all input
signals and cannot be applied selectively.
A configured delay time is referenced to a
sample rate of 48 kHz. In the case of input
signals with a sample rate of 48 kHz the
delay range is 0 to 340 milliseconds in
1-millisecond steps. For other sample rates
the time must be linearly scaled. For exam-
ple, for a sample rate of 96 kHz the actual
time range is 0 to 170 milliseconds. In this
case selecting a delay of 120 on the Model
77 will result in an actual time delay of 60
milliseconds. For 192 kHz sampling the
time range is 0 to 85 milliseconds. Select-
ing a delay of 240 will result in a time delay
of 60 milliseconds.
For operating flexibility two different input
delay values can be selected and stored
during the configuration process. These
can then be enabled as required by the
operator during normal system operation.
The default value for both Delay A and
Delay B is 0 milliseconds. Typical applica-
tions would require only one input delay
to be configured. But in other cases two
different, both non-zero, input delay values
will be selected. This could be appropriate
in applications where multiple video dis-
play systems are being used in the same
control room or monitoring facility. Each
video display may exhibit its own process-
ing latency and audio would need to be
“lined up” accordingly. During normal
StudioComm operation an operator can
select the appropriate input delay for the
display system currently being utilized.
Surround to Stereo Downmix
Levels
The surround to stereo downmix function
is a useful tool for checking the compat-
ibility of surround (5.1) input signals with
stereo and monaural playback environ-
ments. The exact technical formula for how
the Model 76D handles the surround to
stereo downmix function can be selected
by way of four configurable parameters.
The default settings create a good general-
purpose function that’s effectively used by
numerous users of Studio Technologies’
StudioComm for Surround products. But
there are application-specific situations
where modifying one or more of the
parameters will be appropriate. This can
be in response to a personal choice in
monitoring methods or, more frequently,
to meet the requirements of international
broadcast standards.
When the surround to stereo downmix
function is active the path from the left (L)
channel input to the left post-fader output
channel and the right (R) channel input to
the right post-fader output channel is main-
tained. A configuration choice allows the
level of the L and R inputs routed to the L
and R outputs to be selected. By default,
when the surround to stereo downmix
function is active the level of the L and R
inputs remain at unity, with no gain or loss
applied. An alternate setting allows the
level of L and R input channels to be re-
duced (attenuated) by 3 dB. (The available
changes in signal level can also be notated
as 0 dB or –3 dB.)