Abstract: A system for actively controlling pressure pulses in a gas turbine engine combustor is provided, wherein the system includes a means for sensing pressure pulses in the combustor, a first processing means for determining the amplitude and frequency for a predominant pressure pulse of the sensed pressure pulses, a second processing means for calculating an amplitude, a frequency, and a phase angle shift for a cancellation pulse to offset the predominant pressure pulse, and an air bleed means for periodically extracting metered volumes of air from the combustor to produce the cancellation pulse, the air bleed means being controlled by the second processing means. The air bleed means includes a bleed manifold in flow communication with the combustor, a first valve in flow communication with the bleed manifold for controlling the amplitude of the cancellation pulse, and a second valve in intermittent flow communication with the first valve to control the frequency and phase angle shift of the cancellation pulse.