Hammond Skx PRO Reference Manual page 192

ORGAN Voice Section
172
To turn the Vibrato or Chorus effect "ON" for the
Swell Manual of a vintage B-3 / C-3, press the top
of the VIBRATO SWELL tilt tab.
To turn the Vibrato or Chorus effect "ON" for the
Great Manual of a vintage B-3 / C-3, press the
top of the VIBRATO GREAT tilt tab.
To turn the Vibrato or Chorus effect "OFF" for the
Swell or Great Manuals of a vintage B-3 / C-3, press the
tilt tabs at the bottom.
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SKX PRO Reference Guide
To turn the Vibrato or Chorus effect "ON" on the
UPPER Keyboard of the SKX PRO, press the UPPER
button "ON" (LED lit).
To turn the Vibrato or Chorus effect "ON" for the
LOWER Keyboard of the SKX PRO, press the LOWER
button "ON" (LED lit).
To turn the Vibrato or Chorus effect "OFF" for the
UPPER or LOWER Keyboards of the SKX PRO, press the
buttons "OFF" (LED's not lit).