Studio Technologies 68A 2001 - Manual (Page 37)

Model 68A/69A User Guide Issue 1, March 2001
Studio Technologies, Inc. Page 37
for Surround
Mono-to-Center Polarity
It’s worthwhile to note that a polarity inver-
sion takes place whenever the mono-to-
center function is active. By design, the
input signals experience a 180-degree
inversion in the Model 68A’s mono-to-
center combining circuitry. This should not
cause a problem as monitoring audio
signals over a single loudspeaker is con-
sidered polarity insensitive. Only during
electrical testing would this condition be
detected.
Model 68A to Model 69A
Connections
Figure 8 gives a detailed view of the sig-
nals that connect between the Model 68A
Central Controller and the Model 69A
Control Console. The Model 68A provides
+15Vdc power for the Model 69A. The
Model 69A generates MIDI system-exclu-
sive messages and sends them to the
Model 68A. From the outside world, the
remote control input sources connect to
the Model 68A. They then route, via the
interface cable, from the Model 68A to
the actual input circuitry, located in the
Model 69A.
Pin Signal Direction
1 Power Supply Common 68A to/from 69A
2 +15Vdc 68A to 69A
3 Data (MIDI System-Exclusive) 69A to 68A
4 Data Common 69A to/from 68A
5 Remote Mute All 68A to 69A (Note 2)
6 Remote Dim 68A to 69A (Note 2)
7 Spare Remote Input 68A to 69A (Note 2)
8 Remote Input Select 68A to 69A (Note 2)
9 Remote Control Common 68A to/from 69A
Notes: 1) Connector types on Model 68A and Model 69A are
9-pin D-subminiature female. Connectors use 4-40
threaded inserts for locking with mating plug.
2) Remote control sources connect to D-sub on Model
68A, then passively route to Model 69A via 68A/69A
interface D-sub.
Figure 8. Connections between Model 68A and
Model 69A