Studio Technologies 50 2000 - Manual (Page 34)

Issue 4, July 2000 Model 50/51 User Guide
Page 34 Studio Technologies, Inc.
StudioComm equipment is designed to
interface with audio signals that have nom-
inal signal levels of –10dBV and +4dBu.
You might wonder why dBV came into the
picture. Most people don’t realize that
equipment that utilizes “–10” levels usually
mean –10dBV—substantially different from
–10dBu (–10dBV = –7.78dBu). The dBV
designation is simply a different way of
measuring signal level and is often used
when dealing with portable or consumer
audio equipment. The dBV designation
refers to dB referenced to 1.0V, rather than
dBu which refers to 0.7747V.
“Hot” Disconnection of the Model 51
Control Console
Should you need to relocate the Model 51
while your StudioComm system is operat-
ing, there is no reason why you can’t
disconnect the 5-conductor cable, move
the unit, and then connect it again. If the
Model 51 is disconnected while it is oper-
ating, the current operating parameters
are saved in nonvolatile memory and the
Model 50 Central Controller will continue
to operate as it did when the link was
broken. No clicks, pops, or other noises
will occur when the Model 51 is again
connected. The Model 51 will go through
its standard power-up sequence, send a
message to reset power-up defaults, then
send the operating parameters as stored
in its memory. You may notice a brief
interval of silence while the Model 50
responds to the reset defaults message.
Control Room Mono Function
Many arguments where had while design-
ing the control room monaural function.
Was the function supposed to be a true
mono function, sending the sum of left
and right to a separate mono control room
output? Was mono to be the sum of left
and right sent to both left and right chan-
nels? What about level build up with phase
coherent signals that are in both the left and
right channels? After much head scratching
it was realized that the mono function that
most people are accustomed to is really a
means of observing the character of a
stereo mix, and not a “true” mono function.
To observe the stereo image of a mix you
need to sum the left and right signals, drop
the level of the sum by 3dB, and send the
result out the left and right outputs. This is
what virtually all recording consoles imple-
ment, and is what the StudioComm does,
too! We understand that specialized appli-
cations such as mastering and film mixing
may require a more exotic mono function.
Sorry, our hardware simply can’t support it!
Talent Amplifier Mono Function
The Model 35 and Model 38 Talent
Amplifiers each contain a monaural switch.
The mono function sums the left and right
input signals, drops the level of the sum by
3dB, and sends the sum to both the left and
right outputs. This is consistent with the
mono methodology discussed in the previ-
ous paragraph. Please refer to that note for
details.
Input Level and the Talent Amplifiers
Optimal performance of the Model 35 and
Model 38 Talent Amplifiers depend on
the headphone source signal levels being
at approximately the nominal input level,
either –10dBV or +4dBu, depending on
the configuration. The headphone volume
is adjusted only by the level controls on the
talent amplifiers. If the selected headphone
source signal level is significantly less than
nominal, the talent amplifier will simply not
be able to create the maximum volume in
the headphones. While there is some gain