Yamaha GC2020C - Manual (Page 8)

What’s an Expander/Gate?
5
GC2020C Compressor/Limiter Owner’s Manual
English
What’s an Expander/Gate?
The GC2020C features a expander/gate that is independent
of the compressor/limiter. Expander/gate is a function that
effectively eliminates hum or noise that would otherwise be
heard during silent portions of the program. It works by
closing the gate to cut off the output signal when the input
signal falls below a specified level (the gate threshold level). Normally you will set the gate level below the lowest level of
the musical portion, so that the gate will always be “open”
during the music to let the signal pass. Hum or noise that is
lower in level than the music will thus be effectively elimi-
nated.
Setting Up the Expander/Gate
1. Adjust the input level so that the PEAK indicator just
lights up at the loudest signals.
2. Without playing the instrument, gradually raise the Gate
Threshold Level, and set it at a position slightly above the
point where noise is no longer audible.
3. Input a signal and check that its decay is not cut off
unnaturally for the most softly played notes. If the tail
end of the decay is cut off, lower the Gate Threshold
slightly.
Music Signal
Noise
Time
Level
• EXP GATE Function
INPUT SIGNAL
Music Signal
Noise
Signals in
this range
muted Signals in
this range
muted Signals in
this range
muted
Expander gate
threshold level
Time
Level
OUTPUT SIGNAL