BSS Audio FDS-318 User Manual page 23

3-way:
Use this mode for a conventional stereo 3-way speaker system where each of
the three bands operate over different, non overlapping frequency ranges. The
extra two (stereo pair) outputs which do not form part of the crossover system
are available as a full range buffer output operating over the whole frequency
range of 20Hz to 20kHz. These can be useful to drive small full range speaker
systems in ancillary areas, or act as line drivers with level and mute controls to
drive a tape machine recording a show.
2-way HI, 2-way MID, 2-way LO:
Use these modes for a conventional stereo or multichannel (up to four) 2-way
speaker system where each of the two bands operate over adjacent frequency
ranges. Select the 2 WAY HI mode when a crossover frequency is required
within the range of 2kHz to 20kHz. Select the 2 WAY MID mode when a
crossover frequency is required within the range 200Hz to 2kHz. Select the 2
WAY LO mode when a crossover frequency is required within the range 20Hz
to 200Hz.
23