A dual power source pulse generator in power connection with a pair of electrodes having a first electrode, a second electrode and an air gap therebetween. The dual power source pulse generator includes a first pulse source producing a high voltage low current pulse across the pair of electrodes to allow dielectric breakdown, and a second pulse source electrically connected in parallel with an output of the first pulse source, and producing a low voltage high current pulse to thereby produce a current flow of high-density plasma between the same electrodes of the pair of electrodes in response to the high voltage low current pulse.