Studio Technologies 68 V.1 - Manual (Page 19)

Model 68/69 User Guide Issue 2, June 1999
Studio Technologies, Inc. Page 19
for Surround
Reference Level
For audio-with-picture applications it’s
critical that mixing be done in reference
to a known monitor loudspeaker level. This
is often referred to as mixing to “85dB” on
the monitors. The Model 69 Control Con-
sole allows a precise monitor output level
to be stored, and then enabled by pressing
the button labeled REF. Setting the refer-
ence level is very simple:
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 con-
figuration mode. Be certain that the
reference and dim functions are not
active.
3. Use the Model 69 Control Console
to select the desired reference signal
source, e.g., pink noise, as the active
input source.
4. Observing the SPL meter, adjust the
Model 69’s rotary level control until the
desired reference output level has
been reached.
5. Being careful not to touch the position
of the rotary level control, enter the
configuration mode by pressing and
holding the configuration button lo-
cated on the Model 69’s back panel.
6. Once the configuration mode has been
entered, the monitor output signals will
mute. Press and hold the reference
button until its associated LED lights.
This will take approximately 5 sec-
onds. The LED lights to indicate that a
“snapshot” of the new reference level
has been taken.
7. To store the new reference level in
memory, exit the configuration mode
by again pressing and holding the
configure button.
This level is now permanently stored as
the reference level. Only by repeating the
procedure can the value be changed.
Once the configuration mode has been
exited, the monitor output channels will
again become active. Confirm that the
correct level has been stored by pressing
the REF button. The SPL meter should
again display the desired level. If not,
repeat the calibration procedure.
You might wonder why you have to press
and hold the reference button for 5 sec-
onds before the selected value is stored.
This is provided specifically so that some
Bozo won’t accidentally change the refer-
ence level while they are playing around in
the configuration mode! Only if you know
the “secret” will you be able to store a new
value.
Monitor Output Muting
The Monitor Output Muting configuration
allows selection of the method used for
muting the monitor output channels when-
ever the mute all or channel mute/solo
functions are active. Each of the monitor
output channels contains an electrome-
chanical relay, providing loudspeaker-
protection-muting during AC mains power
up and power down. These same relays
can also be used to mute the output chan-
nels during operation of the mute all or
channel mute/solo functions. An alterna-
tive muting method is also available,
utilizing the solid-state analog switches
that are part of the input circuitry. In most
cases using the relays is preferred, as
they provide the most complete muting.