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Progress In Electromagnetics Research
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MODELLING AN IRONLESS LOUDSPEAKER BY USING THREE-DIMENSIONAL ANALYTICAL APPROACHES

By R. Ravaud and G. Lemarquand

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Abstract:
This paper presents some improved three-dimensional expressions of the magnetic field created by tile permanent magnets uniformly and radially magnetized for the design of ironless loudspeaker structures. All the expressions determined have been reduced to compact forms. We use these expressions for the optimization of ironless loudspeaker structures in which the radial field must be radially uniform. Indeed, as ring permanent magnets radially magnetized are rather difficult to manufacture, these magnets are replaced by assemblies of tile permanent magnets radially and uniformly magnetized. We present an example of ironless loudspeaker structure that has been optimized with our threedimensional approaches.

Citation:
R. Ravaud and G. Lemarquand, "Modelling an ironless loudspeaker by using three-dimensional analytical approaches," Progress In Electromagnetics Research, Vol. 91, 53-68, 2009.
doi:10.2528/PIER09021104
http://www.jpier.org/PIER/pier.php?paper=09021104

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29., , http://www.univ-lemans.fr/∼glemar.


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