Transparent panel-form loudspeaker

A method of making a transparent panel-form loudspeaker including a rectangular transparent panel with length a and width b under the condition that b is less than or equal to a to be capable of sustaining flexural vibration over the area of the panel, said method including steps of:

• (a) analyzing the distributions of the modal parameters, which include natural frequencies, modal amplitudes, mode shapes and phase angles, in the modal analysis of said transparent panel which is driven by a preselected number of transducers to generate flexural vibration of said panel and supported peripherally by a flexible suspension device consisting of a continuous corrugated cloth type support and several discrete supports, said modal parameters varying according to values of the design parameters of said transparent panel-form loudspeaker including the ratio of elastic modulus to density of the material used to fabricate said transparent panel, the ratio of length to thickness of said panel, locations of said transducers and said discrete supports on the peripheral edge of said transparent panel;
• (b) analyzing a sound pressure level spectrum generated by said transparent panel-form loudspeaker, said sound pressure level spectrum also varying according to values of said design parameters of said panel-form loudspeaker;
• (c) identifying the favourable modal parameters which are beneficial to sound radiation and the unfavourable modal parameters which have adverse effects on sound radiation;
• (d) selecting values of said design parameters resulting in suppressing the adverse effects of the unfavourable modal parameters, magnifying the beneficial effects of the favourable modal parameters, and achieving a desired sound pressure level spectrum over a specific frequency range;
• and
• (e) making said transparent panel of said panel-form loudspeaker with said selected values of said design parameters.