Studio Technologies 76 V.1.10 - Manual (Page 28)

Issue 7, August 2012 Model 76/77 User Guide
Page 28 Studio Technologies, Inc.
for Surround
Surround to Stereo
When the surround to stereo downmix
function is enabled the LS, RS, and C
channels associated with a surround
signal are combined (“folded down”) with
the L and R signals to create a 2-channel
stereo (left and right) signal. The resulting
stereo signal, sometimes known as LoRo,
is routed to the L and R monitor output
channel. The C, LFE, LS, and RS monitor
output channels are muted. By utilizing this
downmix function phase relationships and
inter-channel level issues can be quickly
observed.
Note that a configuration setting allows the
LFE channel to be routed to both the L and
R outputs when surround to stereo down-
mix is active. As such, if this configuration
is selected the LFE channel won’t mute
when the surround to stereo downmix
function is active.
Stereo to Mono
The stereo to mono downmix function
combines the left and right audio channels
to create a single-channel monaural sig-
nal. This signal is sent out the C (center)
monitor output channel while the L, R, LS,
RS, and LFE monitor output channels are
muted.
Note that when a surround input source
is selected for monitoring, the surround
to stereo downmix function will automati-
cally enable whenever the stereo to mono
downmix function is enabled. This ensures
that an operator will hear a mono signal
created by folding down all channels asso-
ciated with the selected surround input.
The Model 77 associates the state of the
downmix functions with the currently se-
lected input. For example, if surround B is
the selected input source and surround to
stereo downmix is enabled, the condition
will be “remembered” when switching to a
stereo input source. Upon returning to sur-
round B as the input source, the surround
to stereo downmix function will again be-
come active.
Note that a specific downmix function can
only be enabled when it is applicable for
the currently selected input source. This
means that the surround to stereo down-
mix function can only be enabled when a
surround (5.1) input source is selected.
Bandpass Filter for Stereo to Mono
Downmix
A bandpass filter can be inserted into the
path of the stereo to mono downmix signal.
This allows the simulation of the response
of a loudspeaker associated with an inex-
pensive monaural television or portable
radio. This special feature has been in-
cluded to assist an operator in determin-
ing compatibility with “real-world” playback
environments. The filter passes signals in
the range of 100 Hz to 5 kHz, while reject-
ing those above and below. For a detailed
technical description of the bandpass filter
please refer to the Technical Notes section
of this guide.
To enable the bandpass filter feature
requires knowing a “secret” button push
method. But it’s not much of a secret, as
you simply press and hold the stereo to
mono downmix button for two seconds
to enable the function. From that point
forward, whenever the stereo to mono
downmix function is enabled the bandpass
filter will also be enabled. To indicate that
the bandpass filter is enabled, the LED
associated with the downmix mono button
will flash whenever its associated func-
tion is enabled. To disable the bandpass
function, press and hold the stereo to