A system for reducing noise of a noise generator such as a fan located in a housing includes a short duct directing air to the fan housing. An input transducer is located in the duct at a position further removed from the fan than a cancellation noise source which is also located in the duct. An electronic controller with embedded frequencies related to the steady state operation of the fan inputs cancellation signals to the cancellation source. The input transducer also responds to the random noise of the fan to provide control signals to the controller for generating signals for the cancellation source. The input duct can be multi-cellular with respect of the input transducer and the cancellation source.
