Studio Technologies 76DA V.4.00 - Manual (Page 22)

Issue 3, July 2012 Model 76DA/77 User Guide
Page 22 Studio Technologies, Inc.
for Surround
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 sur-
round and stereo digital and analog moni-
tor output levels in either an attenuation
mode or an SPL mode. In the attenuation
mode the output level is shown as a reduc-
tion 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 turned 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). It is used in
conjunction with the reference level in dB
SPL configuration and the stored reference
level. The SPL mode allows a user to see
a visual representation of the SPL level
that is present in the listening environment.
While it takes a little more care to correctly
implement the SPL display mode, it can
offer an enhanced experience for Studio-
Comm 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 digital and analog
monitor outputs are at their reference level,
either through activating the reference level
function or manually 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 con-
figured over a range of 70.0 to 100.0 dB in
1.0-dB steps. In many applications select-
ing a value of 85 would be appropriate,
reflecting the widely used audio-for-picture
85 dB monitoring reference 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.
Dim Level
The dim function is used to reduce the
post-fader surround and stereo digital and
analog monitor output levels by a preset
amount. The reduction is in dB relative to
the post-fader surround and stereo monitor
outputs’ current level. There are four dim
level values available: –10.0, –15.0, –20.0,
and –25.0 dB.