The player editor contains two major features.  The first is the oscilloscope.  This is the black box in the center of the window.  It is only active when a song is playing.  The oscilloscope shuts off when MacMod Pro is moved to the background to save processor time.  The oscilloscope shows the sound waveform going through the speaker.

Below the oscilloscope is a scrolling box containing volume controls for each of the current song's voices.  There are 32 volume sliders since a song can contain up to 32 voices.  The sliders not being used are dimmed and will not operate.