Specifications

Allows process the audio signal independently of the sound level but regarding the signal dynamic range. It is mixed with the
standard compression scheme.
Take a piece of full mixed music, set the ratio to 3-4 and the compression will start working. Now set the threshold of the
compressor to the maximum value, the compressor will stop working because the sound level will never reach the threshold.
Then increase the Hysteresis and you will see (and hear) the compression working again!!! Now decrease or increase the
input gain and you will see that the compression will continue to work equally; it's totally, completely independent of the
sound level and depends only on Ratio, Knee and sound content.
How can this be used? When you have too much dynamic in the sound, going for e.g. from -3, -6 dB Vu (or less) to +12 dB;
If you want to compress the low levels you will hear the sound "pumping" when the sound reaches the High levels and the
only thing to do with standard compressor will be to increase the threshold to rescue some airiness in the sound. But when
doing that the compressor will not work any more on the low levels and you will hear some sound differences (in term
density, live space, grain etc…) especially when the compressor starts working. With Hysteresis, adjust the threshold and
ratio on the High levels to what you think OK, then increase the Hysteresis (from 20 to 50 %) and listen now the low levels
and especially the transition between Low and High levels. You can also start increasing the ratio to increase the effect.
You'll then notice that the compression will always be active but can still take care of High, loud levels (unless you set 100%
hysteresis) and make the compression very smooth and no more pumping… In addition with the Angel Share function, you'll
be able to set a constant and very natural envelop that allows to increase low levels, low frequency and to keep important
transients.
Hysteresis Threshold (65)
Sets the gain range of the hysteresis parameter.
Up: Increasing of the Hysteresis Threshold
Down: Decreasing of the Hysteresis Threshold
The current Hysteresis Threshold value is reflected by two green lines on the Dynamic Activity display.
For Compressor and DCompressor sections, the hysteresis action is effective only when the orange Dynamic Activity (33)
exceeds the area between the two green lines.
For Expander and DExpander sections, the hysteresis action is effective only when the orange Dynamic Activity (33) stays
inside the area between the two green lines.
Hysteresis Maximum (66)
When engaged, the threshold for the processing is determined by the maximum values from RMS/peak detection OR from
the signal dynamic detection. The Hysteresis Threshold is still active, but the Hysteresis mix button is disabled.
This feature allows the whole process to be more reactive to the signal content. It worth being tried on drum tracks.
Threshold (67)
Unit: dB - Value Range: -32 to +16 (Compressor/DCompressor) -80 to +16 (Expander/DExpander)
Default Value: 0
Sets the threshold of the specific dynamic processing section. This dB scale refers to an RMS value.
The threshold effective value is modified by the Hysteresis, the Hysteresis Threshold and, the Hysteresis Maximum settings.
Ratio (68)
Unit: dB - Value Range: 1 to 10 - Step: 0.01
Default Value: 1
Sets the ratio of the specific dynamic processing section.
4.2 Alchemist The Parameters
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