User Guide

Model 780-01/790 User Guide Issue 4, December 2020
Studio Technologies, Inc. Page 37
for Surround
mute all is active. Note that if mute all is
enabled via the remote mute all function,
the mute all LED will flash.
Dim
The dim function is provided for user con-
venience, allowing the post-fader moni-
tor output level to be reduced by a fixed
amount. The Model 790’s configuration
mode allows the dim level to be selected
from among four choices: 10, 15, 20, or
25 dB. Pressing the dim button will enable
the function. The dim button is always set
to “latch” the function on and off. The 4-
digit display, when selected for output level
mode, will indicate the revised post-fader
monitor output level. When dim is active
the post-fader monitor output level reduc-
tion will apply no matter whether the level
is being set by the rotary level control or by
the reference level button. The LED asso-
ciated with the dim button will light when-
ever dim is active. If dim mode is enabled
via the remote dim function the dim LED
will flash.
It’s worth using a few sentences to discuss
the auto dim off function. Whenever dim
is enabled due to the dim button being
pressed, and the rotary level control is
active (reference level mode is not active),
changing the setting of the rotary level
control will automatically turn off dim. The
auto dim off function is a unique attempt
at protecting the aural health of users. No
longer will there be a heart-stopping blast
of audio when the dim button is pressed,
supposedly to enable dim, but actually
turning dim off because it was already
enabled. It’s hard to explain unless you’ve
experienced this in person—trust us, this
situation can and does happen!
Note that the auto dim off function is not
active whenever dim is enabled due to
the remote dim function being active. This
allows remote control equipment, such
as a talkback system, to reliably dim the
monitor outputs.
LFE Low-Pass Filter
The LFE low-pass filter function is pro-
vided to emulate the processing done by
some distribution formats to the signal
present on an LFE channel. Unlike the
seven main surround channels, an LFE
channel is typically bandwidth restricted
to save digital “bits.” It’s important that an
audio mix maintains its integrity when such
LFE bandwidth restrictions are in place.
When enabled the LFE low-pass filter
function applies a filter with a –6 dB cutoff
frequency of 120 Hz and a slope of 48 dB-
per-octave to the selected surround input
source. To enable the LFE low-pass filter
function simply press the LFE low-pass
button. The associated LED will light when
the filter is active in the LFE audio path.
Philosophy dictates how the filter function
should be used. The function can be used
as a final “double check” to ensure that
material will maintain overall integrity when
digitally processed. Enabling the filter
during a final listening session should find
the spectral content remaining constant.
If the mix is impacted, content has been
incorrectly routed to the LFE channel! It’s
also acceptable to leave the filter enabled
at all times. This will ensure that an audio
mix will “hold up” when processed. How-
ever, this may mask content remaining in
the LFE channel which, although it won’t
be present after processing, may be con-
fusing to mastering engineers or other
personnel who monitor the original source
material.