anchor: Source:setFilter
  Sets a low-pass, high-pass, or band-pass filter to apply when playing the Source.
  success = Source:setFilter( settings )
  settings table The filter settings to use for this Source, with the following fields:
  settings.type FilterType The type of filter to use.
  settings.volume number The overall volume of the audio. Must be between 0 and 1.
  settings.highgain number Volume of high-frequency audio. Only applies to low-pass and band-pass filters. Must be between 0 and 1.
  settings.lowgain number Volume of low-frequency audio. Only applies to high-pass and band-pass filters. Must be between 0 and 1.
  success boolean Whether the filter was successfully applied to the Source.
  Source:setFilter()