Methods and apparatus for the supply of non-invasive positive pressure ventilation by motor-driven blowers, and having fast acceleration between treatment pressures, are described. A blower (12) supplies treatment pressure of air or breathable gas to a patient mask (16) via a conduit (14) at a first pressure and at a second, higher pressure. The blower (12) receives its power from a power supply (22) and cascaded motor controller (20). The power supply (22) has the capacity to supply sufficient power for the first pressure to be achieved. A static capacitor (24), that is charged by the power supply (22), provides the energy to the blower (12) to achieve the second pressure, during which period the power supply (22) is effectively shut down.