All 'PACE-Net' stations support the compressor/limiter function with a freely selectable setting for the following values, based on the peak measurement:
- Attack time
- Release time
- Threshold value
- Soft knee
- Gain
- Ratio
The real-time behavior of the compressor/limiter is displayed by opening the context menu (right-click) and activating the 'Show Compressor/Limiter' entry.
'Enable'
The compressor/limiter is enabled when the 'Enable' button is activated (green).
'Threshold'
Threshold value where the compressor/limiter function starts to work and where gain reduction occurs.
The compressor/limiter is adjustable from -40 dB to +20 dB, facilitating applications from low-level compressing to high-level limiting.
'Ratio'
Ratio of analog audio input signal to output signal. Defines the intensity of the signal processing. For example, if the ration selected is configured 2:1 and the input signal increases 10 dB, the analog audio output signal is only increased by 5 dB.
Adjustable from 1…50 in quarter steps.
'Knee Depth'
'Knee Depth' is the 'soft knee' area in dB, on both sides of the threshold value. Setting this parameter to be near zero implements a 'hard knee' with a sharp transition and provides a more noticeable compression.
'Soft knee' is a softer transition where the ratio gradually grows from 1:1 to a set value in a transition region on both sides of the threshold value. It makes the compression effect less perceptible. The adjustable range is 0…60 dB
'Gain'
'Gain' is the gain stage to compensate a loss in level caused by the compressor/limiter. 'Gain' can be used as a digital gain stage with an inactive compressor, with a threshold value of 0 dB in a 1:1 ratio. The adjustable range is −20...+20 dB.
'Attack'
'Attack' is the response to signal levels above the threshold value and is defined by the attack time. The attack time is the amount of time that the unit takes to attenuate the analog audio output level after the threshold value has been reached. Adjustable from 0…200 ms.
'Release'
'Release' is the time required to restore the gain to normal after the input signal has decreased below the threshold level.
Proper release time will depend on the type of signal being processed and the way in which the compressor/limiter is being used. Adjustable from 0…1020 ms.
The right graphic gives a precise overview of the changing audio level caused by the current settings of the compressor/limiter.
The yellow dot shows the level of the analog audio output signal and the red bar the current compressing level with a maximum indicator. In case of expanding, a green bar is shown, also with a trailing peak indicator.