Engineers dealing with noise reduction in habitations close to transportation traffic or indus-trial facilities encounter several problems to decrease noise level in rooms at low frequencies. Passive materials and current building construction knowledge en ...
We present a concept of "active material" with variable acoustic properties, being constituted of an electroacoustic transducer which acoustic impedance can be changed by an active mean. Among the different ways to obtain variable acoustic properties on an ...
The poor acoustic comfort of usual commercial products is often perceived as annoying. Today, more and more companies have realized that sound can be an important component of product attributes and image. They are interested in having acoustic guidelines ...
Speech recognition applications embedded on a PDA are already available on the market. The usual hardware for this kind of systems is a single microphone mounted on the PDA, giving good results within quiet environments. Though, the recognition rate falls ...
Variable acoustic properties can be obtained on an electroacoustic transducer’s voicing face by very basic control strategies, among which are the shunting of the loudspeaker (shortcut, variable electric load, or negative resistance disposals). It is prove ...
When it comes to designing active control disposals, sound pressure sensing is usually required. In the framework of active control of acoustic impedance, this work aims at conceiving a digital estimator that processes voltage and current measurement to co ...
Nowadays, customers have legitimate requirements as regards quality that marketing and consumers departments attempt to satisfy. The sound is well-known to enhance or detract from our pleasure in possessing or using a product. Sound quality engineering is ...
Low frequency background noise (below 200 Hz) is perceptible in many situations such as in room acoustics or industrials issues. Generate by numerous type of source (traffic noise, aircraft, industrial plants, electricity transformer,… ), this type of nois ...
