e. Pre-amplifiers. The pre-amplifier is used with signals from microphones or phono cartridges.
Its primary purpose is to amplify signals from a low level input.
f. Relay System. The relay system can sometimes be DC operated and operates the warning
lights. Its primary purpose is to prevent feedback by muting loudspeakers in the presence of live
Controls. The controls for an audio console usually consist of master pots, channel pots,
program selector switches, and VU meters.
a. Master Pots. The master pots are used to regulate the overall output of the board. Once the
master pots are set up using a 1 KHz tone, they remain as they are until the entire board is neutralized.
b. Channel Pots. The channel pots are used to regulate the output of the individual channels.
Channel pots must be adjusted to their individual sources.
c. Program Selector Switches. Program selector switches usually consist of keys or
interlocking pushbuttons which are used for rapid selection of inputs to the console. Program selector
switches are used to program sound source, monitor a sound source for auditioning or to neutralize a
d. VU Meters. VU meters are used to measure the average of the complex waves which come
from the console. There are usually two meters.
e. Remote Channel. These pots connect the remote lines to TB (talk-back), CUE (monitor
output), or MIX (over the air) (Pot 8).
f. Network Channel. Pot 9 is the network channel and can be used as input for a 600 ohm
network input such as an off-the-air tuner, or cart tape machine.
g. Nemo Channel. The nemo channel as referred to here; is not used as a remote input. The
use of the term here refers simply to a high level channel which has been provided for auxiliary use (Pot
h. Line Amp Feed Switches. The line amp feed switches are the tab key selector switches
located above Pot 10. Line amp feed, key AL3, may be amplified for simultaneous feed from both
i. VU Meters. There are two VU meters located in the center of the audio console. The meter
on the left is the program VU meter while the one on the right is used for addition.
j. VU Selector Switch. The VU selector switch allows for monitoring of AL1, AL3, and
network on the audition VU meter. AL2 and utility are not used.
k. Monitor Bank. The monitor bank is the area directly below the two VU meters. It consists
of six smaller dials, a talk button and a small speaker.