Studio Technologies 58 2000 - Manual (Page 43)

Issue 4, December 2000 Model 58/59 User Guide
Page 44 Studio Technologies, Inc.
for Surround
Model 59 will flash simultaneously as
confirmation of a remote control signal
being active.
When remote bypass is activated, the
mute all LED on the Model 59 will flash, as
will the remote activity LED. The A/B
output select LED will light, indicating the
active monitor output. If configured to do
so, the A/B button will continue to function
during remote bypass.
Technical Notes
Monitor Output Gain Structure
The Model 58 Central Controller’s monitor
outputs are configured for unity gain.
When the rotary level control on the Model
59 Control Console is set for maximum
level (fully clockwise) the output level is
essentially the same as the main input
level. Trim potentiometers allow precise
adjustment of the monitor output level.
This was provided so that slight level
variations caused by the Model 58’s cir-
cuitry and the associated power amplifiers
could be “trimmed out.”
Linking Multiple Model 58 Units
Included with each Model 58/Model 59
base configuration is a ribbon-cable bus
assembly that includes four 9-pin D-sub
plugs (males). This allows the interconnec-
tion of up to four Model 58 units, creating,
in the 2-channel mode configuration, an
8-channel monitoring system. Should a
special application require the intercon-
nection of more than four Model 58s, there
is no problem in creating a custom bus
assembly. All pins of the 9-pin D-subs are
simply connected one-to-one. There is no
practical limit to the number of D-subs
that can be part of the bus assembly.
If rack space or other considerations
prevent the Model 58 units from being
directly adjacent to each other, there is
no problem creating an extended bus
assembly. Note also that the two 9-pin
D-subs on the Model 58 are internally
connected in parallel. Clarity for the user
is the only reason that the connectors are
labeled differently. This means that a
ribbon-cable bus assembly, such as pro-
vided by Studio Technologies, isn’t the
only means of interconnecting Model 58s.
Individual 9-pin to 9-pin D-sub cables can
be used to link Model 58s, utilizing both
the to/from control console and loop thru
connectors.
Input and Output Levels
The main inputs, inserts, and outputs were
designed for a +4dBu nominal operating
level. It was anticipated that signals with
lower operating levels may also get con-
nected. While it was not practical to di-
rectly support multiple operating levels the
circuitry was specifically designed so that
operating level changes could easily be
performed by a qualified technician. The
Model 58/Model 59 schematic diagrams
are available upon request from the fac-
tory. Checking the “fine print” on the Model
58 schematic pages, you’ll find the resistor
identification numbers and corresponding
values to change the main input nominal
level to –10dBu operation. (The Model
58’s designer is well aware that “–10”
signals are supposed to be referenced to
dBV, but finds from experience that a
nominal level of –10dBu interfaces better!)