Relevant bibliographies by topics / Electrodynamic loudspeakers

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Electrodynamic loudspeakers'

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Published: 26 October 2023

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Journal articles on the topic "Electrodynamic loudspeakers"

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Ravaud, Romain, Guy Lemarquand, Valérie Lemarquand, and Tangi Roussel. "Ranking of the Nonlinearities of Electrodynamic Loudspeakers." Archives of Acoustics 35, no. 1 (2010): 49–66. http://dx.doi.org/10.2478/v10168-010-0004-6.

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AbstractThe aim of this paper is to present a way of ranking the nonlinearities of electrodynamic loudspeakers. For this purpose, we have constructed a nonlinear analytic model which takes into account the variations of the small signal parameters. The determination of these variations is based on a very precise measurement of the electrical impedance of the electrodynamic loudspeaker. First, we present the experimental method to identify the variations of these parameters, then we propose to study theoretically the importance of these nonlinearities according to the input level or the input frequency. We show that the parameter which creates most of the distortions is not always the same and depends mainly on both the input level and the input frequency. Such results can be very useful for optimization of electrodynamic loudspeakers.
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Mayrhofer, Dominik, and Manfred Kaltenbacher. "Investigation of a new method for sound generation – Advanced Digital Sound Reconstruction." e & i Elektrotechnik und Informationstechnik 138, no. 3 (2021): 148–54. http://dx.doi.org/10.1007/s00502-021-00876-3.

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AbstractThe current loudspeaker market has a high demand for portable audio devices. Hence, the miniaturization of loudspeakers (microspeakers) is of great importance for manufacturers. Traditional loudspeakers – for example the electrodynamic loudspeaker – are the forerunners, but so-called MEMS loudspeakers (Micro-Electro-Mechanical-System) have emerged recently. MEMS devices have already been used for sensors (i.e., microphones) to a great extend due to their advantages regarding form factor and production efficiency. Albeit additional challenges for actuators like moving enough air with a microstructure – as it is the case for a loudspeaker – the usage of MEMS technology for loudspeakers is very attractive.Since especially low-frequency audio signals often pose problems for microspeakers, this article focuses on a new sound generation technique called Advanced Digital Sound Reconstruction (ADSR) which is especially well-suited for low-frequency audio signals since ADSR can generate more volume displacement relative to its size. Based on a general description of the principle, an outlook of the possibilities regarding achievable sound pressure compared to the classical excitation scheme is derived. Furthermore, measurements are presented, which aim to prove the concept of ADSR based on already existing actuators.
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Steere, John F. "Acoustically enhanced electrodynamic loudspeakers." Journal of the Acoustical Society of America 121, no. 5 (2007): 2481. http://dx.doi.org/10.1121/1.2739140.

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Kaltenbacher, M., M. Rausch, H. Landes, and R. Lerch. "Numerical modelling of electrodynamic loudspeakers." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 18, no. 3 (1999): 504–14. http://dx.doi.org/10.1108/03321649910275189.

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Erza, Mehran, Etienne Gaviot, Guy Lemarquand, et al. "A Versatile Model of Nonlinear Electrodynamic Loudspeaker Co-Operating with the Amplifier Designed by Way of Advanced Software." Archives of Acoustics 39, no. 1 (2015): 51–63. http://dx.doi.org/10.2478/aoa-2014-0006.

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Abstract Sound processing with loudspeaker driving depends critically on high quality electroacoustic transducers together with their relevant amplifiers. In this paper, the nonlinear effects of electrodynamic loudspeakers are investigated as regard the influence of the changes of their main descriptive parameters values. Indeed, while being operated nonlinear effects observed with loudspeakers are due to changes of such constitutive parameters. Regarding either current or voltage-drive, an original model based on Simulink R is presented, taking account of all the electrical and mechanical properties closely associated with nonlinear behaviours. Moreover, as such a Simulink R model may be combined with the PSpice R advanced software, the behaviour of both loudspeaker and amplifier can be exhaustively investigated and optimized. To this end, the amplifier is simulated thanks to the Orcad-Capture-PSpiceR software prior to match with the loudspeaker model with the so-called SLPS co-simulator. Then, values of the current flowing through the loudspeaker can be determined and plotted considering voltage controlling. Obviously in this case current-drive has not to be assessed. This way to proceed allows us to highlight any critical information especially due to the voice coil displacement, yielded velocity, and acceleration of the diaphragm. Indeed our approach testifies to the imperative necessity of mechanical measurements together with electrical ones. Then, considering a given amplifier-loudspeaker association with specific parameters changes of the latter, the entailed nonlinear distortion allows us to qualify and criticize the whole design. Such an original approach should be most valuable so as to match the best fitted amplifier with a given electrodynamic loudspeaker. Then non linear effects due to voltage and current-drive are compared highlighting the advantages of an apt currentcontroled policy.
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Cai, Yinshan, Longlei Dong, and Yanxin Zhou. "A narrowband active noise control algorithm considering the harmonic distortion of the loudspeaker." International Journal of Applied Electromagnetics and Mechanics 64, no. 1-4 (2020): 229–35. http://dx.doi.org/10.3233/jae-209326.

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Electrodynamic loudspeakers are the main actuators of the active noise control system, and their harmonic distortion has a detrimental effect on the noise reduction of the system. To improve the performance, this paper proposes a novel narrowband active noise control algorithm with compensating the nonlinearity of the loudspeaker. In the proposed algorithm, the parameters of the controller are obtained by iteration through the filtered-x least mean square algorithm. Meanwhile, they are adjusted in real-time by establishing the online inverse model of the loudspeaker using the Volterra expansion. The simulation experiments for the typical loudspeaker model show that the proposed algorithm can dramatically improve noise reduction compared to the conventional algorithm.
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Lemarquand, G., R. Ravaud, I. Shahosseini, V. Lemarquand, J. Moulin, and E. Lefeuvre. "MEMS electrodynamic loudspeakers for mobile phones." Applied Acoustics 73, no. 4 (2012): 379–85. http://dx.doi.org/10.1016/j.apacoust.2011.10.013.

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Lemarquand, V., G. Lemarquand, E. Lefeuvre, et al. "Electrodynamic MEMS: Application to Mobile Phone Loudspeakers." IEEE Transactions on Magnetics 48, no. 11 (2012): 3684–87. http://dx.doi.org/10.1109/tmag.2012.2203798.

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Evreinov, E. Grigori, and V. Alexander Agranovski. "Modification of electrodynamic loudspeakers for 3‐D spatialization." Journal of the Acoustical Society of America 105, no. 2 (1999): 934. http://dx.doi.org/10.1121/1.426308.

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Ravaud, R., G. Lemarquand, and T. Roussel. "Time-varying non linear modeling of electrodynamic loudspeakers." Applied Acoustics 70, no. 3 (2009): 450–58. http://dx.doi.org/10.1016/j.apacoust.2008.05.009.

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Dissertations / Theses on the topic "Electrodynamic loudspeakers"

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Holmström, Caroline. "Modeling and Compensation of Nonlinear Distortion in High Efficient Electrodynamic Loudspeakers." Thesis, Luleå tekniska universitet, Signaler och system, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-81219.

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Loudspeakers transform electrical energy into acoustic waves but most of the electrical energy is lost as heat. It is possible to increase the electro-acoustic efficiency by changing the electrical, mechanical or acoustical design of the loudspeaker but with these changes come unwanted side effects. An efficient loudspeaker exhibits strongly nonlinear behavior, but the nonlinear effects can be reduced by the means of implementing an algorithm on a digital signal processor. This is of great interest for Axis Communications since it makes it possible to increase the efficiency in their products without loss of sound quality. The purpose of this thesis was to investigate nonlinear distortion in high efficient electrodynamic loudspeakers using a simulation software, COMSOL Multiphysics, and to model the nonlinear response of the loudspeaker behavior. The simulations were conducted in order to get an understanding of the nonlinear behavior but also to estimate data for the theoretical model. Further, a nonlinear model describing the voice coil excursion was investigated with the purpose of constructing a nonlinear filter able to reduce nonlinear distortion. The result of the simulation showed it was possible to estimate the force factor as a function of voice coil displacement and that it also should be possible, according to the magnetic fields and streamlines, to obtain the function that describes the voice coil inductance from the same simulation of the loudspeaker. The numerical implementation of the voice coil excursion showed the voice coil was operating in the wrong domain when it was driven with a real input signal. Hence, the Volterra series need further work before a nonlinear filter can be derived.
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Руденко, Іван Леонідович. "Планарна електродинамічна акустична система". Master's thesis, КПІ ім. Ігоря Сікорського, 2019. https://ela.kpi.ua/handle/123456789/30597.

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Проведено огляд історії розвитку виробництва перетворювачів та електродинамічних перетворювачів. Приведено повну класифікацію гучномовців та їх принцип дії. Здійснили глибокий аналіз конструкції електродинамічних перетворювачів та їх принцип дії. Приведені основні елементи конструктивних рішень. Виконано моделювання конструктивного рішення планарного електродинамічного перетворювача. Виконано моделювання роботи магнітної та коливальної системи. Приведено графіки основних результатів моделювання та експериментальних вимірювань. Структура та об’єм роботи: дипломна робота складається з вступу, 3 розділів, висновків, списку використаної літератури. Загальний обсяг дипломної роботи складає (106) сторінок. Робота містить рисунків, (48) таблиць (20) та список використаних джерел із (12) найменувань.<br>A review of the history of the production of converters and electrodynamic transducers was conducted. The full classification of speakers and their principle of action are given. The deep analyzes of the structures of electrodynamic transducers and their principle of action are carried out. The basic elements of constructive decisions are given. The simulation of the constructive decision of a planar electrodynamic converter is executed. The simulation of the work of the magnetic and oscillating system is performed. The graphs of the main results of simulation and experimental measurements are presented. Structure and volume of work: the thesis consists of the introduction, 3 chapters, conclusions, list of used literature. The total volume of the thesis is (106) pages. The work contains drawings, (48) tables (20) and list of sources used from (12) names.
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Fitzpatrick, Michele. "Electrodynamic driver for the space thermoacoustic refrigerator (STAR)." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23204.

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Approved for public release; distribution is unlimited<br>The objective of the STAR project is to test and space qualify a new continuous cycle cryogenic refrigeration system for cooling of sensors and electronics which is based upon the newly discovered thermoacoustic heat pumping effect. The new refrigerator has no sliding seals, a cycle frequency of about 300 hz, and uses acoustic resonance to enhance the overall power density and efficiency. This thesis is concerned specifically with the design and testing of the electrodynamic transducer which is responsible for the electro-acoustic power conversion. A computer model of the driver/resonator system is presented along with the techniques for measurement of the electrical and mechanical parameters used as input for the model. A final driver design (including dimensional drawings) utilizing a modified JBL 2450J neodymium-iron-boron compression driver and associated leak tight electrical feed-throughs, microphone, accelerometer, pressure gage, pressure housing, and resonator interface is provided. Keywords: Electrodynamic loudspeaker, Thermoacoustic refrigerator<br>http://archive.org/details/electrodynamicdr00fitz<br>Lieutenant, United States Coast Guard
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Lebrun, Tristan. "Modélisation multi-physique passive, identification, simulation, correction et asservissement de haut-parleur sur des comportements cibles." Electronic Thesis or Diss., Sorbonne université, 2019. http://www.theses.fr/2019SORUS686.

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Cette thèse porte sur la modélisation du haut-parleur électrodynamique, son émulation et son contrôle. Pour la modélisation, on adopte une approche par composants s’appuyant sur les systèmes hamiltoniens à ports. Plusieurs phénomènes, linéaires ou non, sont ainsi traités puis agrégés dans un cadre multi-physique. Une attention particulière est portée à l’impact des effets thermiques sur les composants électrique et mécanique, pour lesquels on introduit des modèles conservatifs irréversibles originaux. Les simulations montrent que des comportements complexes connus sont régénérés. Un premier contrôle en boucle ouverte est élaboré pour supprimer les distorsions, par platitude différentielle. Afin de fournir au correcteur les paramètres des non-linéarités du modèle, une méthode d’estimation ad hoc est proposée. Celle-ci combine une séparation de la mesure en sous-signaux (organisés par ordre homogène de non-linéarité) et l’optimisation d’une fonction de coût (renforçant le contraste entre les ordres). Après validation numérique, les méthodes d’estimation et de contrôle sont appliquées sur un banc de test. Les paramètres physiques estimés sont cohérents mais les signaux temporels re-simulés indiquent la nécessité d’améliorer le modèle en très basse fréquence et de recourir à des ordres homogènes élevés.Le correcteur temps réel conduit à une réduction mesurable des distorsions sur la pression acoustique. En complément, un autre contrôle en boucle ouverte est développé pour compenser l’effet Doppler dû au mouvement de la membrane. Enfin, des méthodes sur le contrôle en boucle fermée sont proposées. L’une cible l’absorption acoustique en combinant « loi de contrôle en temps fini » (pour l’efficacité) et « passivité » (pour la robustesse). L’autre, plus générale, élabore un procédé de connexion « mi-physique, mi-numérique » entre un système physique et un contrôleur numérique qui rend la passivité insensible au retard introduit par le calculateur temps réel<br>This thesis concerns electrodynamic loudspeaker modeling, simulation and control. Regarding modeling, we adopt a component-based approach that relies on port-Hamiltonian systems. Several linear and nonlinear phenomena are thus modeled and then aggregated in a multi-physical framework. Particular attention is paid to the impact of thermal effects on electrical and mechanical components, for which we introduce new irreversible conservative models. The simulations regenerate known complex behaviors. A first open-loop control is developed to eliminate distortions by differential flatness. In order to provide the controller with the model's nonlinearity parameters, an ad hoc estimation method is proposed. This combines a separation of the measurement into sub-signals (organized in a homogeneous order of non-linearity) and the optimization of a cost function (improving the contrast between orders). After numerical validation, estimation and control methods are applied on a test bench. The estimated physical parameters are consistent but the re-simulated time signals indicate the need of improvement of the model at very low frequency and to use higher homogeneous orders. The real-time corrector leads to a measurable reduction of the distortions on the sound pressure. In addition, another open-loop control is developed to compensate for the Doppler effect due to the movement of the membrane. Finally, methods on closed-loop control are proposed. One targets acoustic absorption by combining "control law in finite time" (for efficiency) and "passivity" (for robustness). The other, more general, develops an "half-physical, half-digital" method of connection between a physical system and a digital controller that makes the passivity insensitive to the delay introduced by the digital signal processor
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Bouvier, Damien. "Identification de systèmes non linéaires représentés en séries de Volterra : applications aux systèmes sonores." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS162/document.

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Cette thèse porte sur l’identification de systèmes non linéaires représentables en séries de Volterra, et son application à des systèmes sonores. Les séries de Volterra, qui permettent de représenter une large classe de systèmes non linéaires, correspondent à un développement en série organisé par ordre d'homogénéité par rapport à l’entrée: chaque terme homogène est caractérisé par un noyau convolutif dont l’ensemble fournit une "signature complète" du système représenté. Les travaux présentés reposent sur le développement d’une étape préalable de séparation des termes de la série pour améliorer l’identification des noyaux de Volterra. Par rapport aux méthodes déjà existantes de séparation en ordres homogènes, basées sur des relations d’amplitudes entre signaux tests, l'approche adoptée dans cette thèse consiste à exploiter les relations de phase entre signaux afin d'obtenir une méthode robuste. Cela est tout d’abord obtenu de manière abstraite pour le cas de signaux d’excitations complexes. De cette idée, plusieurs méthodes adaptées au cas des signaux réels sont développées. Ceci amène à définir de nouvelles catégories de signaux pour décrire la sortie d’une série de Volterra, regroupant les contributions selon leurs propriétés de phase. Les méthodes de séparation proposées sont testées et appliquées à une pédale d’effet de guitare. Ensuite, des méthodes d’identification spécifiques aux nouveaux types de signaux sont présentées. Enfin, une méthode d’estimation des paramètres d’une représentation d’état à non-linéarités polynomiales est développée. Celle-ci est appliquée à un haut-parleur électrodynamique, dont les caractéristiques non linéaires sont étudiées<br>This thesis addresses the identification of nonlinear systems that can be represented with Volterra series, and its application to audio systems. Volterra series give an input-output representation, approximated to within a given error, of any time-invariant continuous nonlinear system with fading memory. Technically, they correspond to a series expansion sorted by homogeneity order with respect to the input: each homogeneous term is characterized by a convolutive kernel whose set provides a "complete signature" of the modelled system. The works presented are based on the development of a preliminary step that consists in separating the series' terms to improve Volterra kernels' identification. Compared to existing homogeneous order separation methods, which are based on amplitude relationships between test signals, the approach chosen in this thesis is to exploit phase relationships between signals to obtain a robust method. This is first obtained in the theoretical case of complex excitation signals. From this idea, several methods suited to the use of real signals are developed. This leads to define new signals categories that describes the output of a Volterra series, sorting nonlinear contributions according to their phase properties. The proposed separation methods are applied and tested on a guitar pedal effect. Then, specific identification methods for the new types of signals are presented Finally, a method for estimating the parameters of a polynomial nonlinear state-space representation is developed. This is applied to an electrodynamic loudspeaker whose nonlinear characteristics are studied
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Maillou, Balbine. "Caractérisation et identification non-paramétrique des non-linéarités de suspensions de haut-parleurs." Thesis, Le Mans, 2015. http://www.theses.fr/2015LEMA1028.

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Ce travail de thèse porte sur le comportement mécanique en basses fréquences de l'équipage mobile du haut-parleur électrodynamique, et plus spécifiquement de ses suspensions. Les propriétés des suspensions sont difficiles à identifier du fait de l'assemblage géométrique mis en oeuvre et du fait des matériaux employés, à l'origine de comportements viscoélastiques non-linéaires. En régime linéaire, le modèle de Thiele et Small permet une bonne description du comportement du haut-parleur, l'équipage mobile étant modélisé par un système masse-ressort-amortissement linéaire. En régime non-linéaire, ce modèle n'est plus suffisant et la démarche adoptée est celle de l'identification de systèmes non-linéaires, outil d'aide à la modélisation analytique. Un modèle sans a priori physique est choisi : le modèle « Hammerstein Généralisé ». Son identification requiert l'acquisition de signaux expérimentaux. Un banc de mesure a donc été élaboré et permet de caractériser l'équipage mobile découplé du moteur magnétique, lorsqu'il est soumis à un déplacement axial de grande amplitude et imposé par un pot vibrant. Le pot vibrant étant lui-même non-linéaire, une nouvelle méthode d'identification du modèle « Hammerstein Généralisé » a été développée, adaptée à la configuration de systèmes non-linéaires en série. Enfin, les paramètres d'un modèle dit de «Thiele et Small étendu» sont déduits à partir des paramètres du modèle «Hammerstein Généralisé» et permettent de mettre en évidence l'évolution de la raideur et de l'amortissement avec la fréquence d'excitation et le déplacement de la membrane, ainsi que la dépendance des phénomènes observés avec le niveau d'excitation<br>This thesis deals with the low frequencies mechanical behavior of the electrodynamic loudspeaker moving part, and especially with the suspensions, whose properties are among the most difficult to identify because of both assembly geometry and intrinsic materials, leading to nonlinear viscoelastic behaviors. In small signal domain, the Thiele and Small model describes the behavior of the whole loudspeaker with a good fit, the moving part behavior being modeled by a simple linear mass-spring system, with mass, damping and stiffness parameters. In large-signal domain, this model is no longer sufficient. Our approach is then to perform nonlinear system identification as a tool helping to improve analytical models. A model without physical knowledge is chosen : « Generalized Hammerstein ». Its identification requires the acquisition of experimental signals. A multi sensor experimental set up were so carried out and allows to characterize the whole moving part of a loudspeaker, without magnetic motor, attached to a rigid stand and excited with high axial displacement values, by means of a shaker. Shaker being itself a nonlinear device, a new method of « Generalized Hammerstein » model identification was developped, dedicated to nonlinear systems in series. Finally, parameters of an «expanded Thiele and Small» model are derived from the «Generalized Hammerstein» model parameters. This allows to highlight the evolution of the stiffness and damping with the frequency of excitation, with the displacement of the membrane, as well as the dependence of observed phenomena with the excitation level
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Book chapters on the topic "Electrodynamic loudspeakers"

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Beranek, Leo L., and Tim J. Mellow. "Electrodynamic loudspeakers." In Acoustics: Sound Fields and Transducers. Elsevier, 2012. http://dx.doi.org/10.1016/b978-0-12-391421-7.00006-3.

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Beranek, Leo, and Tim Mellow. "Electrodynamic loudspeakers." In Acoustics: Sound Fields, Transducers and Vibration. Elsevier, 2019. http://dx.doi.org/10.1016/b978-0-12-815227-0.00006-6.

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"Electrodynamic Loudspeaker Drivers." In Electroacoustics. CRC Press, 2013. http://dx.doi.org/10.1201/b13859-18.

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Conference papers on the topic "Electrodynamic loudspeakers"

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Madagalam, Mallikarjun, Paolo La Torraca, Mukhtar Ahmed, et al. "Screen-Printed Flexible Circular and Rectangular Silver Spirals for Planar Electrodynamic Loudspeakers: A Comparative Study of Pressure Frequency Response." In 2022 6th IEEE Electron Devices Technology & Manufacturing Conference (EDTM). IEEE, 2022. http://dx.doi.org/10.1109/edtm53872.2022.9798156.

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Merabti, Hocine, Daniel Massicotte, and Wei-Ping Zhu. "Electrodynamic Loudspeaker Linearization using a Low Complexity pth-Order Inverse Nonlinear Filter." In 2019 IEEE International Symposium on Signal Processing and Information Technology (ISSPIT). IEEE, 2019. http://dx.doi.org/10.1109/isspit47144.2019.9001831.

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Iwai, Kenta, and Yoshinobu Kajikawa. "Modification of second-order nonlinear IIR filter for compensating linear and nonlinear distortions of electrodynamic loudspeaker." In 2017 25th European Signal Processing Conference (EUSIPCO). IEEE, 2017. http://dx.doi.org/10.23919/eusipco.2017.8081698.

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