PURPOSE: To reduce a noise by applying a pressure change of a reverse phase of a combustion sound and silencing it in a burner.

CONSTITUTION: A pressure change of a combustion sound is detected as a sound pressure by a microphone 19 provided in a combustion chamber 14, a reverse phase signal of the sound is calculated based on the signal by a calculator 20, and input to a proportional valve 10. The change of the reverse phase is output from the valve 10 thereby to cancel a flame vibration generated in the chamber 14 by a phase interference. A signal detected by the microphone 19 is mixed with a signal fed through a fixed filter in which transmission characteristics from the valve 10 to the microphone 19 are realized at the reverse phase signal by a differential amplifier, and fetched to the calculator thereby to suppress generation of hawling. A silencing amount can also be evaluated based on the signal of the microphone 19, the sound varied by an adaptive control is always minimized, the sound is reduced, and generation of vibrating combustion is also prevented.