Studio Technologies 76B 2012 - Manual (Page 11)

Model 76B/77B User Guide Issue 3, August 2012
Studio Technologies, Inc. Page 11
for Surround
Metadata Input
The Model 76B allows a source of Dolby E
metadata to be directly connected. Hard-
ware and software inside the Model 76B
extracts (“parses”) one of the dialnorm
data elements from the connected meta-
data signal. This dialnorm value can be
viewed on the Model 77B’s LED display
and, if desired, used to control the monitor
output levels. Refer to the Technical Notes
section of this guide for details.
The metadata signal is connected by
way of a 9-pin D-subminiature connector,
labeled RS-485/Remote Control Inputs,
which is located on the back panel of the
Model 76B. Refer to Figure 5 for exact
connection details. While only the data +
and data – connections are absolutely
necessary, a shield connection can also
be made. Note that the connections for
the metadata signal are reminiscent of
the SMPTE 207M standard.
The metadata signal must be in the form
of RS-485 or RS-422 asynchronous serial
data. This differential signal must have a
data rate of 115.2 kbit/s and a data format
of 8 data bits, no parity, and 1 stop bit
(8-N-1). A metadata signal of this type
is commonly available on metadata-
generating or de-embedding equipment
from broadcast equipment manufacturers
such as Dolby Laboratories®, Evertz®,
and NVISION®.
While in hardware the Model 76B’s RS-485
input connection is bi-directional, in soft-
ware it’s configured only to receive data.
This means that there’s no reason why
a signal already connected between two
other pieces of equipment can’t also be
connected in parallel (“bridged”) with the
Model 76B’s metadata input.
A word of advice—Studio Technologies
has found documentation supplied with
some metadata-generating equipment has
incorrect (or at least confusing) pin-out
information. This has resulted in much
head scratching and hair pulling. As such,
it may be valuable to use a logic analyzer
Signal Signal
Connections High (+) Low (–) Shield
L 24 12 25
R 10 23 11
C 21 9 22
LFE 7 20 8
LS 18 6 19
RS 4 17 5
Auxiliary L 15 3 16
Auxiliary R 1 14 2
Notes: 1) All signals transformer-coupled digital audio;
selectable for AES3 or AES3id compatibility.
2) Connector type on Model 76B is 25-pin
D-subminiature female (DB-25F). Installer must provide
male (DB-25M). Connector uses 4-40 threaded inserts
for locking with mating plug.
3) Wiring scheme follows TASCAM DA-88 convention.
Standard DA-88-type wiring harnesses are directly
compatible, with the exception of 4-40 screw threads
being required.
Figure 4. Connections for Surround and
Auxiliary Monitor Outputs
Signal Pin Direction
RS-485 Data + 7 Input
RS-485 Data – 2 Input
Data Shield 1 Shield
Remote Mute All 5 Input
Remote Dim 6 Input
Remote Aux Monitor Out On/Off 8 Input
Remote Spare 9 Input
Remote Input Common 4 Common
Note: Connector type on Model 76B is 9-pin D-subminiature
female (DE-9F) Connector uses 4-40 threaded inserts
for locking with mating plug.
Figure 5. Connector Pin Outs for Metadata and
Remote Control Inputs