Publications de Etienne Thierry Jean-Luc Rivet

Broadband Nonreciprocal Acoustic Propagation Using Programmable Boundary Conditions: From Analytical Modeling to Experimental Implementation

Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar, Gaël Matten

We theoretically, numerically and experimentally demonstrate the acoustic isolator effect in a one-dimensional waveguide with direction-dependent controlled boundary conditions. A theoretical model is used to explain the principle of nonreciprocal propagat ...

American Physical Society (APS)2019

Active acoustic resonators with reconfigurable resonance frequency, absorption, and bandwidth

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Romain Christophe Rémy Fleury, Theodoros Koutserimpas

Acoustic resonators play a key role in the development of subwavelength-sized technologies capable of interacting with airborne audible sound, from its emission and absorption to its manipulation and processing. Specifically, artificial acoustic media made ...

American Physical Society (APS)2019

Low Frequency Sound Field Reconstruction in Non-rectangular Room: A Numerical Validation

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Vu Thach Pham

Characterization of sound fields in rooms has always been a challenging task. A faithful reconstruction of sound fields in rooms generally would require an impractically high number of microphones. At low frequencies, where sound field can be modeled as a ...

2018

Toward Wideband Steerable Acoustic Metasurfaces with Arrays of Active Electroacoustic Resonators

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Romain Christophe Rémy Fleury, Thomas Laurence

We introduce an active concept for achieving acoustic metasurfaces with steerable reflection properties, effective over a wide frequency band. The proposed active acoustic metasurface consists in a surface array of subwavelength loudspeakers diaphragms, ea ...

2018

Constant-pressure sound waves in non-Hermitian disordered media

Stefan Rotter, Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Romain Christophe Rémy Fleury

When waves impinge on a disordered material they are back-scattered and form a highly complex interference pattern. Suppressing any such distortions of a wave’s free propagation is a challenging task with many applications in a number of different discipli ...

2018

Multi-degree-of-freedom low-frequency electroacoustic absorbers through coupled resonators

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

Electroacoustic absorbers represent an interesting solution for low-frequency sound absorption in rooms. These systems simply consist of closed-box electrodynamic loudspeakers, whose acoustic impedance at the diaphragm is judiciously adjusted by connecting ...

Elsevier2018

Design of active Multiple-degrees-of-freedom electroacoustic resonators for use as broadband sound absorbers

Hervé Lissek, Romain Boulandet, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

We present a novel control method achieving stable multiple-degrees-of-freedom electroacoustic resonators. Such broadband absorbers, composed of a feedback-controlled electrodynamic loudspeaker, have many practical applications to real-world acoustic engin ...

2017

On the Optimisation of Multi-Degree-of-Freedom Acoustic Impedances of Low-Frequency Electroacoustic Absorbers for Room Modal Equalisation

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

Low-frequency electroacoustic absorbers have recently been developed as a solution for the modal equalisation. Firstly investigated in waveguides, the technique consists in matching the acoustic impedance at a closed-box loudspeaker diaphragm to the charac ...

2017

Broadband Low-Frequency Electroacoustic Absorbers Through Hybrid Sensor-/Shunt-Based Impedance Control

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

This paper proposes a hybrid impedance control architecture for an electroacoustic absorber, that combines an improved microphone-based feedforward control with a currentdriven electrodynamic loudspeaker system. Feedforward control architecture enables sta ...

Institute of Electrical and Electronics Engineers2017

Sensorless Electroacoustic Absorbers Through Synthesized Impedance Control for Damping Low-Frequency Modes in Cavities

Hervé Lissek, Romain Boulandet, Etienne Thierry Jean-Luc Rivet

This paper presents a concept of sensorless electroacoustic absorber for damping the low-frequency modes in a cavity such as a duct or a room. Taking advantage of the reciprocity of the voice coil transducer, it is shown that a synthetic electrical admitta ...

S Hirzel Verlag2016

Experimental assessment of low-frequency electroacoustic absorbers for room modal equalization in actual listening rooms

Véronique Adam, Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

In listening rooms, low-frequency modal resonances lead to uneven distributions in space and frequency of the acoustic energy, as well as an alteration of the temporal behavior of the original music content. While usual absorption techniques have severe li ...

AES2016

Acoustic energy harvesting using electrochemical double layor capacitors: Technical feasibility and performance assessment

Mario Paolone, Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Dimitri Torregrossa, Sami Driss Karkar

This paper describes a first prototype harvesting the acoustic energy using electrochemical storage devices. In particular, the harvesting system is composed by an Electrochemical Double Layer Capacitors (EDLC) suitably coupled with an electroacoustic abso ...

IEEE2016

Egalisation modale des salles avec des absorbeurs électroacoustiques

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

L’égalisation du champ sonore aux basses fréquences (égalisation modale) est un véritable défi dans les salles d’enregistrement ou dédiées aux systèmes audio. Les résonances modales conduisent à une distribution irrégulière en espace et en fréquence de l’é ...

2016

Room Modal Equalisation with Electroacoustic Absorbers

Etienne Thierry Jean-Luc Rivet

The sound quality in a room is of fundamental importance for both recording and reproducing processes. Because of the room modes, the distributions in space and frequency of the sound field are largely altered. Excessive rise and decay times caused by the ...

EPFL2016

Electroacoustic absorbers for the low-frequency modal equalization of a room: what is the optimal target impedance for maximum modal damping, depending on the total area of absorbers?

Véronique Adam, Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

Electroacoustic absorbers consist of loudspeakers, shunted with an electrical circuit designed to obtain a given acoustic impedance. Their design and principles are now well understood. Unidimensional experiments, using plane waves under normal incidence i ...

2014

Absorbeurs électroacoustiques pour l'égalisation modale des salles : Une nouvelle approche avec des haut-parleurs à double bobine

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

Le défi récurrent dans les salles dédiées aux systèmes audio de haute-fidélité est l’égalisation du champ sonore aux basses fréquences. Selon la position du point d’écoute, la réponse de la salle en ce point peut entrainer des niveaux de pression acoustiqu ...

2014

Baffle Electroacoustique

Hervé Lissek, Romain Boulandet, Etienne Thierry Jean-Luc Rivet

L'invention est relative à un Baffle électroacoustique muni d'un dispositif de réduction active du son sans capteur acoustique. The invention refers to an Electroacoustic baffle with ensorless active sound reduction capabilities. ...

Institut Nationale de la Propriété Industrielle2014

Development of electroacoustic absorbers as soundproofing solutions for industrial ventilation systems

Victor Desarnaulds, Hervé Lissek, Etienne Thierry Jean-Luc Rivet

In many industrial environments, room and cavity modes may severely strengthen the annoyance of low frequency noises, such as in ventilation equipments. Moreover, there is an obvious technological gap in the state-of-the-art relative to low-frequency sound ...

2013

Design of a built-in electroacoustic resonator for active noise reduction

Hervé Lissek, Romain Boulandet, Etienne Thierry Jean-Luc Rivet

The paper focuses on the design of a built-in electroacoustic device for active noise reduction purposes. The device basically encompasses a loudspeaker connected to a synthetic electrical impedance that enhances its ability to dissipate part of the incomi ...

2013

Optimization of electroacoustic resonators for semi-active room equalization in the low-frequency range

Hervé Lissek, Etienne Thierry Jean-Luc Rivet

At low frequencies, standing waves within the room cause large frequency-response variations in the listening environment, such as audio rooms or recording studios. This unwanted phenomenon has a significant impact on the sound quality of an audio system. ...

2013