Yamaha QL5 Reference Manual page 225

 COMPRESSOR
The COMP processor attenuates signals above a specified THRESHOLD by a specified
RATIO.
The COMP processor can also be used as a limiter, which, with a RATIO of ∞:1, reduces the
level to the threshold. This means that the limiter's output level never actually exceeds the
threshold.
Parameter Range
THRESHOLD (dB) –54 to 0 (55 points)
1.0:1, 1.1:1, 1.3:1, 1.5:1, 1.7:1, 2.0:1,
RATIO 2.5:1, 3.0:1, 3.5:1, 4.0:1, 5.0:1, 6.0:1,
8.0:1, 10:1, 20:1, ∞:1 (16 points)
ATTACK (ms) 0–120 (121 points)
44.1kHz: 6 ms – 46.0 sec
RELEASE (ms)
48kHz: 5 ms – 42.3 sec (160 points)
OUT GAIN (dB) 0.0 to +18.0 (181 points)
KNEE Hard, 1–5 (6 points)
• I/O Characteristics • Time Series Analysis
(KNEE= hard,
OUT GAIN= 0.0dB)
THRESHOLD
RATIO
THRESHOLD
Input Level
Description
This determines the level of input signal required to
trigger the compressor.
This determines the amount of compression, that is,
the change in output signal level relative to change
in input signal level.
This determines how soon the signal will be
compressed once the compressor has been
triggered.
This determines how soon the compressor returns to
its normal gain once the trigger signal level drops
below the threshold. The value is expressed as the
duration required for the level to change by 6 dB.
This sets the compressor's output signal level.
This determines how compression is applied at the
threshold. For higher knee settings, compression is
applied gradually as the signal exceeds the specified
threshold, creating a more natural sound.
(RATIO= ∞:1)
Input Signal Output Signal
ATTACK
Time
 EXPANDER
An expander attenuates signals below a specified THRESHOLD by a specified RATIO.
Parameter
THRESHOLD (dB) –54 to 0 (55 points)
1.0:1, 1.1:1, 1.3:1, 1.5:1, 1.7:1, 2.0:1,
RATIO 2.5:1, 3.0:1, 3.5:1, 4.0:1, 5.0:1, 6.0:1,
8.0:1, 10:1, 20:1, ∞:1 (16 points)
ATTACK (ms) 0–120 (121 points)
44.1kHz: 6 ms – 46.0 sec
RELEASE (ms)
48kHz: 5 ms – 42.3 sec (160 points)
OUT GAIN (dB) 0.0 to +18.0 (181 points)
KNEE Hard, 1–5 (6 points)
• I/O Characteristics
(KNEE= hard,
OUT GAIN= 0.0dB)
THRESHOLD
RELEASE
Input Level
RATIO
Time
6
Range Description
This determines the level of input signal
required to trigger the expander.
This determines the amount of expansion.
This determines how soon the expander
returns to its normal gain once the trigger
signal level exceeds the threshold.
This determines how soon the signal is
expanded once the signal level drops below
the threshold. The value is expressed as the
duration required for the level to change by
6 dB.
This sets the expander's output signal level.
This determines how expansion is applied at
the threshold. For higher knee settings,
expansion is applied gradually as the signal
exceeds the specified threshold, creating a
more natural sound.
• Time Series Analysis
(RATIO= ∞:1)
Input Signal
THRESHOLD
Time
Output Signal
ATTACK RELEASE
Time
Data List