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shall be invalid.
Flatten
: all band gain recovery to 0dB.
Narrow Band
: bandwidth (Q), value is smaller than normal.
Normal
: bandwidth (Q), value is common bandwidth.
Wide Band
: bandwidth (Q), value is larger than normal.
3.5.4 Compress
The compressor is to compress the signal by the preset ratio when input signal level more than threshold.
When the input level is more than the preset threshold, the output level is compressed by the ratio set. Signal
Output = Thr (Signal Input - Threshold) / Ratio; if the input level is less than preset threshold, the signal
will be directly output. Signal Output = Signal Input; when the ratio is adjusted by “+∞”, the compressor becomes
as a limiter.
Bypass
: the input signal is bypassed and will not be processed. If it is pressed, the compressor will be
disabled. Otherwise, the compressor will be enabled.
Threshold
: is the initial level of compression. When the signal is more than this limit value, the compression
processing module will be enabled to compress the signal; when the signal is less than this limit value, the
compression processing module will be disabled and the signal input will be fed directly to the output.
Ratio
: the compression ratio of signal over threshold.
Release time
: the time from the level input is less than preset value to that the compressor fully stops
operating.
Attack time
: the time from the level input reaches the threshold to that the compressor starts.
Output
: the actually compressed level value.
3.5.5 AGC
First, the function of AGC is described. For example, when the user speaks facing towards the microphone,
the distance between the mouth and the microphone will fluctuate, causing fluctuating volume output. Though
setting the threshold, AGC outputs the signal input by 1:1 if the level less than threshold while the level over the
