Studio Technologies 58 1998 - Manual (Page 18)

Issue 2, April 1998 Model 58/59 User Guide
Page 18 Studio Technologies, Inc.
for Surround
monitor output level control circuitry; they
are pre-fader (pre-VCA).
The meter outputs are intended for con-
nection to the inputs of various mechani-
cal, electronic, or electromechanical meter
systems. These could range from conven-
tional analog “VU” or “PPM”-type meters,
to projection meter systems used in mo-
tion picture applications. The meter out-
puts can also serve as an additional audio
output for special applications, such as a
copy or “dub” output. In addition, the meter
outputs serve an important role in the input
calibration process, which is discussed in
the Configuration section of this guide.
The meter outputs are unbalanced, have
a nominal level of +4dBu, and are capable
of driving loads of 600 ohms and greater.
Even if the meter outputs are not going to
be used during normal operation it is
important to provide access to them. To
correctly and accurately calibrate the
system input-to-output gain an audio level
measurement device must be able to be
temporarily connected to the meter out-
puts. While not absolutely necessary,
terminating or routing the meter outputs
to points on an audio patch bay may prove
very helpful for long-term maintenance
assistance.
Inserts
The connector labeled INSERTS is used
to interface with the two, 2-channel insert
sections. Please refer to Figure 9 for
details on the exact “pin out” of the D-sub
connector. The use of the insert sections
will depend on the requirements of the
specific installation. In certain cases the
inserts sections won’t be required, and
no connections will need to be made.
The insert sends are electronically bal-
anced, have a nominal level of +4dBu, and
are capable of driving balanced or unbal-
anced loads of 600 ohms or greater. While
balanced operation is preferred, unbal-
anced operation is not 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 optimal unbalanced opera-
tion, it is important to connect both – and
shield together directly on the D-sub, and
not at the other end of the harness.
Note that the insert sends do not have
level trim potentiometers associated with
them. The output levels are nominally
+4dBu, with channel-to-channel variation
of up to ±0.5dB considered normal. It is
anticipated that the equipment connected
to the insert sends will have, if required,
input level adjustment controls.
The insert returns are electronically bal-
anced, have a nominal input level of
Signal Signal
Connection High (+) Low (–) Shield
SEND 1-1 24 12 25
RETURN 1-1 10 23 11
SEND 1-2 21 9 22
RETURN 1-2 7 20 8
SEND 2-1 18 6 19
RETURN 2-1 4 17 5
SEND 2-2 15 3 16
RETURN 2-2 1 14 2
Notes: 1) Connector type on Model 58 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 9. Connector Pin Out for Inserts