Experimental characterization of a shape optimized acoustic lens: Application to compact speakerphone design.

This work presents the shape optimization and subsequent experimental validation of an acoustic lens with application to a compact loudspeaker, such as found in commercial speakerphones. The shape optimization framework is based on a combined lumped parameter and boundary element method model using free form deformation geometry parameterization. To test the optimized design, the loudspeaker lens is three-dimensionally printed and experimentally characterized under anechoic conditions on a finite baffle with respect to its off-axis frequency response.

Achieving a flat, wideband frequency response of a loudspeaker unit by numerical optimization with requirements on its directivity.

This paper demonstrates how significant improvement in frequency response and directivity of a loudspeaker may be obtained by optimizing the local properties of the materials for the diaphragm and surround. Performance is investigated as the considered frequency range and off-axis requirements are progressively expanded. The results are generated by optimizing the values and layout of stiffness, mass, and damping of both the speaker diaphragm and surround.