A request on ventilation systems today is the feature of a low noise level. A common method to attenuate ventilation noise is to use passive silencers. However, such silencers are not suitable for the lowest frequencies and one solution is to use active noise control (ANC) to increase the noise attenuation in the low frequency range. Normally when using a feedforward ANC system to attenuate duc...

In this paper we investigate a new statistical excitation mapping technique to enhance throat-microphone speech using joint analysis of throatand acoustic-microphone recordings. In a recent study we employed source-filter decomposition to enhance spectral envelope of the throat-microphone recordings. In the source-filter decomposition framework we observed that the spectral envelope difference ...

We have developed a prototype wireless microphone that provides vocalists with control over their vocal effects directly from the body of the microphone. A wireless microphone has been augmented with six momentary switches, one fader, and three axes of motion and position sensors, all of which provide MIDI output from the wireless receiver. The MIDI data is used to control external vocal effect...

A new approach for for estimating the acoustic pressure in the near field of a microphone based on non-intrusive direct measurement of acoustic particle velocity is proposed. This method enables the estimation of the acoustic pressure inside a domain located in front of the microphone membrane. The acoustic pressure is calculated using the acoustic particle velocity on the frontiers of this dom...

In acoustic intensity estimation, adding a microphone at the probe center removes errors associated with pressure averaging. Analytical bias errors are presented for a one-dimensional, three-microphone probe for active intensity, reactive intensity, and specific acoustic impedance in a monopole field. Traditional estimation is compared with the Phase and Amplitude Gradient Estimator (PAGE) meth...

The literature on gradient and differential microphone arrays makes a distinction between the two types, and nevertheless shows how both types can be used to obtain the same directional responses. A more theoretically sound rationale for using delays in differential microphone arrays has not yet been given. This paper presents a gradient analysis of the sound field viewed as a spatio-temporal p...

Laboratory evidence suggests that an asymmetric microphone fitting (omnidirectional processing in one ear and directional processing in the other) can provide a directional advantage in background noise that is as great, or nearly as great, as that provided by binaural directional processing (Bentler et al, 2004). The present study investigated whether the potential benefit of an asymmetric fit...

A new rst-order di erential microphone array with an in nitely steerable and variable beampattern is described. The microphone consists of 6 small pressure microphones ush-mounted on the surface of a 3/4" diameter rigid nylon sphere. The microphones are located on the surface at points where included octahedron vertices contact the spherical surface. By appropriately combining the three Cartesi...

An acoustically transparent, configurable microphone array with omnidirectional elements, designed for room acoustics analysis and synthesis, and archaeological acoustics applications, is presented. Omnidirectional microphone elements with 2 mm-diameter capsules and 1 mm-diameter wire mounts produce a nearly acoustically transparent array, and provide a simplified mathematical framework for pro...

Fixed broadband beamformers using small-size microphone arrays are known to be highly sensitive to errors in the microphone array characteristics. This paper describes two design procedures for designing broadband beamformers with an arbitrary spatial directivity pattern, which are robust against gain and phase errors in the microphone array characteristics. The first design procedure optimises...