Studio Technologies 750 - Manual (Page 26)

Issue 3, May 1997 Model 750 User Guide
Page 26 Studio Technologies, Inc.
Model 750
Stereo Line Inputs
The Model 750 contains two identical
stereo line input channels. They are
unique, having the ability to support true
stereo sources, as well as single or two-
channel monaural sources that are com-
mon to broadcast environments. The
circuitry was designed for compatibility
with signals that have a nominal level of
+4dBu. However, nominal signal levels of
–10 to +10dBu are perfectly acceptable.
Level Controls
Two level controls are used to set the
amount of input signal that is sent to the
left/right routing buttons, and subse-
quently on to the main and AUX bus
assignment buttons. The inner knob
controls the level of the left channel input
signal; the outer knob controls the right
channel signal. On the front panel, note
the small arrow graphic symbol and the
letter “U,” located at approximately the
“1-o’clock” rotation position. This indi-
cates the approximate setting for the
level controls to give unity gain.
Status LEDs
Two bi-color LEDs serve as signal
present/peak indicators for the left and
right signals. Electrically they monitor the
output of the left and right level controls.
The LEDs light with the color green when
the signals are 18dB or greater below the
Model 750’s nominal internal operating
level. The LEDs light with the red color
when the signals are within 6dB of the
maximum.
Input-to-Output Channel Routing
From the level controls, the signals pass
to two pairs of channel assignment but-
tons. The assignment buttons allow the
input signals to be routed and, if desired,
combined before being sent to the main
and AUX bus assignment buttons. The
four routing buttons provide a unique and
powerful function, allowing the left and
right input signals to be routed in any
manner desired, not simply the “left input
connects to left output” and the “right
input connects to right output” situation
that is found in most audio mixers. This
flexibility is provided specifically for broad-
cast applications where a source signal
Figure 11. Detail of front panel showing setup
section