The Breath Control tile operates on both blow and draw (pressure and vacuum). The rising output “R” provides a control voltage that rises on a positive pressure (blow) and falls on vacuum (draw). The falling output “F” is an inverted copy of the “R” signal so it falls on pressure and rises on vacuum. The sensitivity “SENS” knob sets how sensitive the CV outputs are to pressure and vacuum. The “OFFSET” knob sets the starting position for the CV outputs. In the center position both outputs will be around 0V. The tile comes equipped with a 1 meter long 3/32 I.D. latex hose fitted with a plastic blow tip.