Being able to define the length of a loop makes it possible to have different sounds playing different subdivisions.
This video shows four loops where the bass drum and the hi-hat are played with different subdivisions of the loop (7vs4 - 28 beat loop / 4vs5 - 20 beat loop / 3vs2 - 18 beat loop / 6vs5 - 30 beat loop)
if the leftmost cell of the frequency value is set, the value is not used to define a fixed frequency, but is used instead to pick a frequency from a table (that defines a 'scale')
this video shows a few iterations with fixed frequency values, then the leftmost frequency cell is set, and as a consequence the frequency value is loaded from a table
Two random modes have been added, both pertaining to the AtariVox: the first generates exclusively AtariVox presets, the second mode generates both AtariVox and 2600 presets.
An example of the second, 'mixed' mode is shown in the following video.