Abstract: A quiet headspace for the passenger in a vehicle (car/train/bus/aircraft etc.) which comprises a canopy to provide some passive attenuation of the noise coming from the surroundings and within the canopy a noise reduction system comprising, in combination one or more loudspeakers and one or more microphones located close to the passenger's head, and one or more microphones located around the periphery of the canopy.

Abstract: An active control system for attenuating tonal noise in a defined region is described. In its most basic form the system includes sensors for generating signals indicative of the residual noise in the region after attenuation and the uncontrolled sound affecting the region, signal processing circuit for processing the generated signals differently depending on the tonal content thereof, an adaptive filter supplied with at least one of the generated signals whose characteristic is controlled by the processing circuitry, a transducer for producing tonal-noise-attenuating disturbance in the region and delay means for delaying signals relating to the uncontrolled noise before or after or during the adaptive filtering. The system finds direct application in a personal headset or ear defender.