Yamaha QY100 Owner's Manual page 237

Reverb effect
Chorus effect
Variation effect
Pattern Mode Effect Connection Display
Note that in the PATTERN mode effect connection display
only the variation stage has accessible controls. The reverb type
for the PATTERN mode effect is always "HALL 1" and the chorus
type is always "CHORUS 1".
Effects & Effect Editing
(Variation effect: INSERTION)
Variation effect INSERTION/
SYSTEM selector
Variation effect
Chorus-to-Reverb
send control
Variation-to-Chorus
send control
Variation-to-Reverb
send control
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