Adds a soft-clip limiter audio effect to an Audio bus. A limiter is similar to a compressor, but it's less flexible and designed to disallow sound going over a given dB threshold. Adding one in the Master bus is always recommended to reduce the effects of clipping. Soft clipping starts to reduce the peaks a little below the threshold level and progressively increases its effect as the input level increases such that the threshold is never exceeded. $DOCS_URL/tutorials/audio/audio_buses.html The waveform's maximum allowed value, in decibels. Value can range from -20 to -0.1. Applies a gain to the limited waves, in decibels. Value can range from 0 to 6. Threshold from which the limiter begins to be active, in decibels. Value can range from -30 to 0.