Kurzweil Forte - Manual (Page 363)

KB3 Programs
KB3 Mode Buttons
D-4
Variation
The Variation button acts as a Slow/Fast switch for the Rotary speaker effect. By default,
the sustain pedal (SW1) also controls Rotary Slow/Fast. You can set the sustain pedal to
function as sustain for all KB3 Programs (instead of Rotary Slow/Fast) by using the Rotary
Override parameter in Global mode. You can also make different Rotary Slow/Fast controller
assignments for each Program or Multi by using the Parameters page in Program Edit Mode
or the Multi Controls page in Multi Edit Mode.