Native Instruments MASCHINE MK3 Manual page 698

The Reflex panel in the Plug-in Strip.
The Reflex in the Control area.
Parameter
ROOM Section
Color
Smooth
Size
OUTPUT Section
Mix
Description
At lower settings, the general sound is a bit more muffled; the
higher the settings, the brighter it sounds.
With this parameter, you can soften the metallic character of
Reflex.
Adjust the size of the virtual room here.
Mix lets you adjust the amount of the effect in relation to the
dry original audio signal.
Effect Reference
Spatial and Reverb Effects
MASCHINE - Manual - 698