Model 750 User Guide Issue 3, May 1997
Studio Technologies, Inc. Page 35
Model 750
Practical Operating Tips
Now that weve reviewed all the sections
that comprise the Model 750, its time to
actually use the unit. In the following
paragraphs some suggestions about how
to best use the Model 750 are provided.
Setting the Bus Operating Levels
The main and AUX master level controls
allow the overall gain structure of the
audio mixing buses to be set. Correctly
setting these controls ensures that maxi-
mum audio quality will be achieved. In
most cases simply setting the controls to
the unity gain position is appropriate; the
unity gain position is clearly marked on
the front panel. If you are a fanatic for
accuracy, you may want set the level
controls precisely using the following
procedure:
1. On the setup section, set the single
tone button to the on (in) position. This
will cause a 400Hz or 1kHz steady tone
to be generated.
2. On the setup section, place the main
bus assignment button to the on (in)
position; the AUX bus assignment
button must be in the off (out) position.
3. Set the meter source button to the
monitor (in) position.
4. Set the monitor source button to main
stereo.
5. Adjust the main master level controls
so that the meters read 0 VU. The
main bus is now set for precisely unity
gain.
6. On the setup section, place the main
bus assignment button to the off (out)
position and the AUX bus assignment
button to the on (in) position.
7. If the AUX interrupt function becomes
active (due to configuration DIP
switches 6 and/or 7 being set to their
on (up) position) the meters are now
monitoring the AUX bus. If the AUX
interrupt function is not active, set the
monitor source to AUX.
8. Adjust the AUX master level controls so
that the meters read 0 VU. The AUX
bus is now set for precisely unity gain.
9. The procedure has now been com-
pleted. Return the buttons on the setup
and monitor sections to the desired
operating setting.
Signal Present/Peak LEDs
Bi-color status LEDs are provided on the
mic/line and stereo line input sections.
Under normal operating conditions the
LEDs should light only with the color
green. Signal peaks may cause an occa-
sional red flash, but sustained lighting of
the peak indicator means that audio per-
formance is being compromised. Adjust
the level controls so that you arent in
the red except on rare occasions.
Limiter/Compressors
While the Model 750 was designed to
provides lots of signal headroom, most
applications, especially broadcast, wont
benefit from it. In fact, wide dynamic
range, in many cases, will simply tax the
transmission chain and lead to signal
degradation. Our feeling is that leaving
the limiter/compressor button to the on
(in) state is your best bet. If you cant think
of a good reason why extended dynamic
range is desired, leave the limiter/com-
pressors active!