Compander (Hard & Soft) - Yamaha CS1D Owner's Manual

Appendices
—This determines the amount of expansion.
RATIO
That is, the change in output signal level relative to
change in input signal level. For a 2:1 ratio, for example,
a 5 dB change in input level (below the threshold) results
in a 10 dB change in output level. For a 5:1 ratio, a 2 dB
change in input level (below the threshold) results in a
10 dB change in output level.
—Select the filter that will be
INPUT FILTER HPF/LPF
applied to the signal immediately before the expander.
When HPF (high pass filter) is on, the expander will
apply to the signal that has passed through the HPF, and
the signal that has passed through the LPF will then be
mixed in.
For COMP ON and HPF ON
LPF
HPF EXPANDER
SELF POST EQ
When LPF (low pass filter) is on, the expander will apply
to the signal that has passed through the LPF, and the
signal that has passed through the HPF will then be
mixed in.
COMPANDER (HARD & SOFT)
The hard (H) and soft (S) companders comprise of com-
pressor, expander, and limiter. The limiter prevents out-
put signals from exceeding 0 dB. The compressor
compresses signals that exceed the threshold level. The
expander attenuates signals below the threshold and
width. The soft compander has an expansion ratio of
1.5:1, while the hard compander has an expansion ratio
of 5:1. The following two graphs show typical com-
pander curves. The one on the left shows the hard com-
pander. The one on the right, the soft compander.
+20
+10
Width
0
–10
–20
–30
–40
–50
–60
–70
–70 –60 –50 –40
Input Level (dB)
Hard Compander
14
+
Threshold
–30 –20 –10 0 +10 +20
For COMP ON and LPF ON
HPF
LPF EXPANDER
SELF POST EQ
If you want the signal immediately after passing
through the LPF or HPF to be used as the key-in
signal for the internal compressor, select SELF
POST EQ as the key-in signal.
When the key-in signal is set to LEFT CH (when
the key-in signal is taken from the previous-num-
bered channel), and if COMP is turned on and LPF
or HPF is also turned on for the channel that is the
source of the key-in signal, then the signal after
passing through the filter will be output as the key-
in signal.
—This turns the input filter on/
INPUT FILTER ON/OFF
off. If off, the LPF/HPF setting will be ignored.
INPUT FILTER FREQUENCY
quency of the LPF/HPF. (The LPF cutoff frequency and
HPF cutoff frequency are always linked.)
+20
+10
Width
0
–10
–20
–30
–40
–50
–60
–70
–70 –60 –50 –40
Input Level (dB)
Soft Compander
+
—This sets the cutoff fre-
Threshold
–30 –20 –10 0 +10 +20