Level-Loc

The "Level-Loc" Audio Level Controller is basically a
low-noise preamplifier with unity gain from the microphone
level input to the microphone level output or
60 dB of voltage gain from the high-impedance microphone
level input to the auxiliary level output. The
input and microphone level output contain matching
transformers so either high- or low-impedance operation
may be selected. In addition, a high-impedance
auxiliary output is provided capable of driving any
high-impedance amplifier, mixer or tape recorder input
requiring 1 volt or less. This preamplifier has the additional
capability of reducing its gain as the input
signal increases, thereby holding the output signal
constant. After a predetermined input level threshold
is reached the output level is "locked", that is, it
remains constant even if the input signal increases
by as much as 100 times (40 dB). This reduction in
gain, which results in a constant output level, is
obtained without introducing significant distortion or
transients into the program material. The DISTANCE
SELECTOR switch determines the input level at which
gain reduction (Level-Loc action) begins.