Methods and apparatus for suppressing noise. The present invention provides a method that includes directing a laser at a first volume of gas and directing microwave radiation to a second volume. The method includes selecting the location of the second volume so that it is overrun by a shockwave system of a supersonic vehicle. Preferably, the directing of the radiation is from a vehicle that flies at high altitude and is of practical length (e.g., 100-400 feet or more). The radiation may be pulsed and steered. The present invention also provides a system including a laser and microwave antenna for controlling the noise of a supersonic vehicle. The laser is directed at a first volume while the antenna is pointed at a second volume that envelops the first volume. The location of the second volume is such that it will be overrun by the shockwave system of the vehicle.