APPENDIX C
GTX
CENTURY SERIES
Stereo Program In
The Stereo Program In section (on the GTx Master section)
controls the way in which the Stereo Program In signal is rout-
ed through the console. Controls for gain, HF/LF EQ, bus
assignment (Mono, L/R, Aux 1/2, Aux 3/4, and Matrix A/B
buses), balance, level, muting, and PFL are included. Red Peak
and green Signal Present LED’s are located next to the PFL
switch.
Stereo Program In Connector
This 1/4-inch jack, usually used for stereo program music,
accepts an unbalanced stereo line level signal. Polarity is as
follows: Tip=Left, Ring=R, Sleeve=Ground
Talkback Assignment Switches
These switches assign the talkback signal to the outputs and/or
auxes. Switches exist for External Talkback Output, Mono
(Center) Bus, Left/Right Buses, Groups, Auxes 1-8 (in pairs),
and Matrices A and B. The same routes are also used when the
oscillator is selected. This overrides the talkback source.
Talkback Level Control
This knob controls the final level of the talkback signal.
Talkback Microphone Input
Found on the top of the master section and under the arm rest
on the right side, these balanced XLR inputs allow for a micro-
phone or other balanced mic-level source to be connected to
the talkback system. Default for this connector is +48V DC. It
is advised to connect only one talkback microphone at a time.
Talkback Enable Switch
This switch activates the entire talkback system including the
internal oscillator.
XLR Balanced Outputs
These outputs are designed to drive both balanced and unbal-
anced input devices without adaptation. Signals are normally
balanced on this output connector. The output will drive all
load impedances from 600 ohms upwards with full perfor-
mance specifications. The output is designed so that if either
pin 2 or pin 3 were intentionally shorted (as in connecting to an
unbalanced input of your next stage of electronics) or acciden-
tally shorted, the output level of the non-shorted connector pin
increases by 6db. This is an amount equal to the normal loss of
a balanced output when one pin of a balanced output is short-
ed. The result is no need for external gain make up.
XLR Microphone Input Connector
Balanced XLR Input is designed to receive professional Low
Impedance microphone signals. The input Gain controls on the
front panel adjust for most input levels. In the event of exces-
sive input levels, the front panel input pad switch should be
pressed. Front panel selection of 48 Volt Phantom power
enables most types of condenser microphones that require such
power to be used. See your device’s operating manual for cor-
rect operation. (If in doubt that your non-condenser micro-
phone may be damaged by using Phantom Power, please make
sure that the front panel phantom power switch on that input
channel is in the off [out] position. Operate this switch with the
channel muted to avoid sending ‘thumps’ to your speakers.)
This input may also be used for low level line input signals,
provided the source (instrument) is able to drive a 5k Ohm or
higher load. (See your instruments or electronics owner’s man-
ual for output impedance.) When line output devices such as
tape players are plugged into the microphone input, special
care should be observed that the phantom power is turned off
on that channel, as damage may result. Because of this, it is
recommended that the 1/4" line input connector be used when
connecting a line level device. 48 Volt Phantom power is not
present on these input connectors, and the impedance of the
line input connector is high enough to accept any line level
device.
