Tracker 4.44
8.7: The extended command 14
For older soundtrackers, extended command 14 was simply a toggle for
the filter (see Set filter).
Protracker extended this: in the case of command 14, phi is interpreted as a
secondary command number, so the parameter is actually plow for these commands.
Note that Glissando control and Invert loop are rarely used.
[1] Note there is not effect 14-8