Studio Technologies 76D V.2.02 - Manual (Page 18)

Issue 2, June 2009 Model 76D/77 User Guide
Page 18 Studio Technologies, Inc.
for Surround
Pre-Fader Surround/Stereo
Input C Direct Monitor Output
Type
To meet the needs of a specific installation
the nominal impedance and level char-
acteristic of the pre-fader surround and
stereo input C direct monitor outputs can
be selected. They are selected as a group;
configuration of individual outputs is not
provided. If the output signals are going
to be connected to balanced AES3 inputs
then the setting that provides a source
impedance of 110 ohms with a nominal
5 Vpp level would be appropriate. If the
output signals are going to be connected
to unbalanced AES3id inputs then the
setting that provides a 75 ohm source
impedance and a nominal output level
of 1 Vpp would be correct.
Post-Fader Surround/Stereo
Monitor Output Type
The source impedance and output level of
the post-fader surround and stereo moni-
tor outputs, as a group, can be configured.
The information previously provided con-
cerning the pre-fader surround and stereo
input C direct monitor output type also
applies to these outputs.
Reference Level
For audio-with-picture applications it’s
often beneficial for monitoring to be done
in reference to a known loudspeaker
level. This is often referred to as “mixing
to 85 dB” on the monitors. The Studio-
Comm for Surround system allows a
precise post-fader surround monitor output
level to be stored, and then enabled by
pressing the Model 77 button labeled
Reference Level. Setting the reference
level is very simple but care is required:
1. Set up a precision sound pressure
level (SPL) measuring device at the
desired listening location.
2. Place the StudioComm system in the
normal operating mode, not the config-
uration mode. Be certain that the dim,
mute all, reference level, and downmix
functions are not active. The remote
mute all and remote dim functions
must also not be active.
3. Use the Model 77 Control Console to
select the input source that contains
the desired reference signal source,
e.g., pink noise.
4. Observing the SPL meter, adjust the
Model 77’s rotary level control until the
desired loudspeaker system reference
level has been reached.
5. Being careful not to disturb the posi-
tion of the rotary level control, enter the
configuration mode by pressing and
holding the configuration button locat-
ed on the Model 77’s back panel.
6. Once the configuration mode has been
entered, all the monitor outputs will
mute. Press and hold the reference
level button; its associated LED will
begin to flash. After five seconds the
LED will light steadily to indicate that
a “snapshot” of the new reference
level has been taken. The Model 77’s
numeric display will then show the
value of the new reference level. The
value shown will always be a negative
number as it’s always a value less than
the maximum output level. The refer-
ence level button can now be released.
7. To complete the process the configura-
tion mode must be exited. This is per-
formed by again pressing and holding
the configure button for two seconds.