Studio Technologies 76D V.2.02 - Manual (Page 19)

Model 76D/77 User Guide Issue 2, June 2009
Studio Technologies, Inc. Page 19
for Surround
The new reference level is now stored
in the Model 76D’s nonvolatile memory.
Only by repeating the entire procedure
can the value be changed.
Once the configuration mode has been ex-
ited, the monitor outputs will again become
active. Confirm that the correct level has
been stored by pressing the reference level
button. The SPL meter should display the
desired level. If not, repeat the calibration
procedure to achieve the desired goal.
You might wonder why you have to press
and hold the reference level button for
five seconds before the selected value is
recognized. This is provided specifically so
that unauthorized users won’t accidentally
change the reference level while they ex-
periment with the configuration mode. Only
if you know the “secret” will you be able to
store a new value.
Overall Display Mode
The Model 77’s 4-digit numeric display
can be configured to display the post-fader
surround and stereo monitor output levels
in either an attenuation mode or an SPL
mode. In the attenuation mode the output
level is shown as a reduction in level, in
dB, relative to the maximum output level.
When the rotary control is used to set the
output level to its maximum the display will
show 0.0. As the rotary control is moved in
the counterclockwise direction the display
will show negative values, reaching –70.0
before the full mute function automatically
mutes the outputs.
In the SPL mode the display can be con-
figured to allow the output level to be
presented to users in terms of the actual
sound pressure level (SPL). Used in con-
junction with the reference level in dB SPL
configuration and the stored reference
level, SPL mode allows a user to see a vi-
sual representation of the SPL level that is
present in the listening environment. While
it takes a little more care to correctly imple-
ment the SPL display mode, it can offer
an enhanced experience for StudioComm
users.
Reference Level in dB SPL
The reference level in dB SPL configu-
ration allows a specific SPL value to be
associated with the stored reference level
value. In this way whenever the post-fader
surround or stereo monitor output is at
the reference level, either through activat-
ing the reference level function or manu-
ally adjusting the rotary level control, the
Model 77’s display will show the configured
SPL level. Whenever the monitor output is
not at the reference value the display will
show the current value, in dB, relative to
the reference level. The reference level in
dB SPL can be configured over a range of
70.0 to 100.0 dB in 1.0-dB steps. In many
applications selecting a value of 85 would
be appropriate, reflecting the widely used
audio-for-picture 85 dB monitoring refer-
ence level. (Typically this 85 dB is really
85 dBC, indicating that a C-weighting filter
has been applied to the measurement.)
Other common reference SPL values,
such as 82 dB and 87 dB, are well within
the allowable range.
Auto Reference Level Off
When auto reference level off is enabled,
the function automatically turns the refer-
ence level function off if a change is made
to the rotary level control while the refer-
ence level function is active.