Expert Sleepers Little Spacey v1.0.0 - Manual (Page 15)

Ducking
Ducking reduces the level of the delays when the signal level is high. This is typically used
to let the initial note ‘cut through’ the delays, with the delays then fading up during the
note’s decay tails.
Speed
Sets the amount by which the envelope modifies the modulation speed. Positive settings
cause the modulation to speed up when the sound is louder; negative settings cause the
modulation to slow down when the sound is louder.
Depth
Sets the amount by which the envelope modifies the modulation depth. Positive settings
cause the modulation depth to increase when the sound is louder; negative settings cause
the modulation depth to decrease when the sound is louder.
Spread
Sets the amount by which the envelope modifies the modulation LFO’s spread.
LFO 2
The LFO 2 section lets you control a second LFO which
modulates the depth of the main modulation LFO.
Speed
Sets the speed of the second LFO.
Depth
Sets the amount by which the second LFO affects the depth of the main LFO.
Spread
Varies the phase of the second LFO applied to each (stereo) channel.