Studio Technologies 68 V.1 - Manual (Page 13)

Model 68/69 User Guide Issue 2, June 1999
Studio Technologies, Inc. Page 13
for Surround
channels associated with that input source
to be easily rerouted. While signals gener-
ated within a facility will normally follow a
specific format, such as left, center, right,
left surround, right surround, subwoofer,
it is possible that media provided by an
outside facility will follow a different one.
L/R Bypass Input
The connector labeled OUTPUTS & L/R
BYPASS INPUT provides access to the
L/R Bypass input. Please refer to Figure
6 for details on the exact “pin out” of the
D-sub connector. It is usual for the source
connected to the L/R Bypass Input to be
from the stereo monitor output of an audio
console, or other monitoring system.
Warning: It is very important that
signals connected to the L/R Bypass
input be “post” a level control, i.e.,
attenuated from line level. Connect-
ing a standard line level audio signal
can result in damage to monitor
loudspeaker systems and, more
importantly, to the ears of listeners.
Balanced sources should be wired so that
signal high is connected to + on the D-sub,
signal low to – on the D-sub, and shield to
the D-sub’s shield connection. With an
unbalanced source the connection method
depends on the requirements of the moni-
tor speaker system’s input. This is be-
cause routing of the L/R Bypass input to
the left and right monitor outputs does not
involve any active circuitry. Whenever the
L/R Bypass feature is active, the signal
connected to the L/R Bypass input is
simply passed through to the left and
right monitor output channels by means
of electromechanical relay contacts.
Monitor Outputs
The connector labeled OUTPUTS & L/R
BYPASS INPUT provides access to
the six monitor output channels. Please
refer to Figure 6 for details on the exact
“pin out” of the D-sub connector.
The monitor output channels are intended
for connection to audio amplifiers associ-
ated with monitor loudspeakers, or to the
inputs of loudspeakers with integrated
amplifiers. The monitor outputs are elec-
tronically balanced and capable of driving
balanced or unbalanced loads of 600
ohms or greater. While balanced operation
is preferred, unbalanced operation does
not pose a problem. To connect to an
unbalanced load connect the + terminal
of the D-sub as signal high, and both the
– and shield as the signal low/shield. For
Signal Signal
Connections High (+) Low (–) Shield
OUTPUT-L 24 12 25
OUTPUT-C 10 23 11
OUTPUT-R 21 9 22
OUTPUT-LS 7 20 8
OUTPUT-RS 18 6 19
OUTPUT-SUB 4 17 5
L/R BYPASS INPUT-L 15 3 16
L/R BYPASS INPUT-R 1 14 2
Notes: 1) Connector type on Model 68 is 25-pin D-subminiature
female. Installer must provide plug (male). Connector
uses 4-40 threaded inserts for locking with mating plug.
2) Wiring scheme loosely follows Tascam DA-88
convention. Modified DA-88-type wiring harnesses are
required, along with 4-40 screw threads.
Figure 6. Connections for Monitor Outputs and
L/R Bypass Input