Yamaha AW4416 Reference Guide - Page 161

Appendix Expander Output Level Output Level dB +20 +10 Expansion ratio = 2:1 0 Knee = hard -10 -20 Threshold = -10dB -30 -40 -50 -60 -70 dB -70 -60 -50 -40 -30 -20 -10 0 +10 +20 Input Level dB +20 +10 Expansion ratio = 2:1 0 Knee = knee5 -10 -20 Threshold = -20dB -30 -40 -50 -60 -70 dB -70 -60 -50 -40 -30 -20 -10 0 +10 +20 Input Level An expander is another form of automatic level control. By attenuating the signal below the threshold, the expander reduces low-level noise and effectively increases the dynamic range of the recorded material. Expander (EXP) parameters: Parameter Value Threshold (dB) Ratio Attack (ms) Outgain (dB) Knee Release (ms) -54 to 0 (55 points) 1.0, 1.1, 1.3, 1.5, 1.7, 2.0, 2.5, 3.0, 3.5, 4.0, 5.0, 6.0, 8.0, 10, 20, ∞ (16 points) 0 to 120 (121 points) 0 to +18 (36 points) hard,1,2,3,4,5 5 ms to 42.3 sec*1, 6 ms to 46.0 sec*2, 8 ms to 63.4 sec*3 (6 points) (160 points) *1. These values are obtained when the sampling frequency is 48kHz. *2. These values are obtained when the sampling frequency is 44.1 kHz. *3. These values are obtained when the sampling frequency is 32 kHz Threshold determines the level of input signal required to trigger the expander. Signals above the threshold pass through unaffected. Signals at and below the threshold level are attenuated by the amount specified using the Ratio parameter. The trigger signal is determined using the KEY IN parameter. Ratio controls the amount of expansion-the change in output signal level relative to change in input signal level. With a 1:2 ratio, for example, a 5 dB change in input level (below the threshold) results in a 10 dB change in output level. For a 1:5 ratio, a 2 dB change in input level (below the threshold) results in a 10 dB change in output level. Attack controls how soon the signal is expanded once the expander has been triggered. With a fast attack time, the signal is expanded almost immediately. With a slow attack time, the initial transient of a sound passes through unaffected. Out Gain sets the expander's output signal level. Knee sets the transition of the signal at the threshold. With a hard knee, the transition between unexpanded and expanded signal is immediate. With the softest knee, knee5, the transition starts before the signal reaches the threshold and gradually ends above the threshold. Release determines how soon the expander returns to its normal gain once the trigger signal level drops below the threshold. Appendix-26 - Reference Guide