User Manual
Table Of Contents
- 1. Hardware
- 2. Technology Overview
- 3. Software
- 3.1 Software Installation
- 3.2 Using the Software
- 3.3 Custom edit processing module
- 3.4 Audio Module Parameters
- 3.4.1 Input Source
- 3.4.2 Expander
- 3.4.3 Compressor & Limiter
- 3.4.4 Automatic Gain Control
- 3.4.5 Equalizers
- 3.4.6 Graphic Equalizer
- 3.4.7 Feedback Suppressor
- 3.4.8 Noise Gate
- 3.4.9 Ducker
- 3.4.10 Ambient Noise Compensation (ANC
- 3.4.11 Auto Mixer
- 3.4.12 Acoustic Echo Cancelation
- 3.4.13 Noise Suppression
- 3.4.14 Matrix
- 3.4.15 High and Low Pass Filter
- 3.4.16 Delay
- 3.3.17 Output
- 3.4.18 USB interface
- 3.5 Settings Menu
- 4. Control
- 5. FAQs
- Appendix A: Module ID Distribution
- Appendix B: Module Parameter Types (1)
ALF-DSP 88-U
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Attack: Attack refers to the time that the expander will wait before activating when the input signal exceeds the
threshold. Shorter attack time allows to start the expander more quickly.
Release time: Release time refers to the delay in time required for the gain to be restored to normal when the input
signal drops lower than the threshold.
No matter the starting time or the release time, it just helps to reduce the speed of gain attenuation. That is to say,
the speed of the gain from -40dB to 0dB is slowed down due to the influence of Attack. The Attack time and Release
time is unrelated to the threshold. If the signal level falls below the threshold, the Attack time and Release time will
have their own respective influence on gain attenuation; when the signal level rises above the threshold, the gain
attenuation produced by the expander will disappear in accordance with the speed controlled by the Release time.
When the gain attenuation is reduced to 0dB, the expander will stop expansion. Later, when the signal reduces to
below the threshold, the expander will start again, and the release time will begin to work.
3.4.3 Compressor & Limiter
Compressor
The compressor is used to reduce the dynamic range of the signal higher than the threshold set by the user, and to
maintain the dynamic range of the signal lower than the threshold. The compressor has the following control
parameters:
Threshold: When the signal level is higher than the threshold, the compressor / limiter begins to reduce the gain.
Any signal that exceeds the threshold is regarded as overshoot signal, and its level will be reduced based on the
ratio set. The more the signal level exceeds the threshold, the more level is attenuated.
Ratio: It refers to the compression ratio. The ratio sets the attenuation degree of the overshoot signal to the
threshold level. The smaller the compression ratio is, the less compression will take place and signal will remain
higher than the threshold. Once the signal exceeds the threshold, the compression ratio decides the ratio of input
signal variation to output signal variation. For example, when the compression ratio is 1:2, if the input signal is 2dB
higher than the threshold, the exceeding part only changes by 1dB. A compression ratio of 1:1 suggests that the
compressor does not attenuate the signal in proportion. The adjustable range of compression ratio is 1-20.
Attack Time & Release Time: In order to maintain natural oscillation, it is generally accepted that part of the
original level will pass through the compression without any influence, or just minor influence. Likewise, if there is
rapid sharp attenuation and rapid recovery in the signal gain, the suction effect will occur. The attack and release
time of the compressor is to avoid this effect. The attack time sets the speed of gain attenuation, while the release
time sets the speed of gain recovery.