Patent ID: 7159938

Claim:
An acoustic structure of seat back comprising: a padding formed in conformity with a predetermined outer shape of said seat back, said padding including a frontal backrest surface area defined forwardly of the seat back, wherein said frontal backrest surface area is recessed in a direction backwardly of the seat back; a plurality of securing holes formed in a central portion of a frontal backrest surface area of said padding; a plurality of speaker units each comprising: a speaker having a frontal side facing to a side forwardly of said seat back; and an enclosure in which said speaker is securely accommodated, with said frontal side of the speaker being exposed therefrom, said plurality of speaker units being secured in said frontal central backrest area of said padding, such that said enclosure is securely fitted in each of said plurality of securing holes, while said frontal side of said speaker is exposed from said each of said plurality of securing holes; a seat back frame provided in said padding; a sound-conductive cushion having a density lower than a density of said padding so as to provide high sound conductivity relative to the padding; said sound-conductive cushion being securely juxtaposed on said frontal backrest surface area so as to cover said frontal side of said speaker associated with each of said plurality of speaker units; wherein said sound-conductive cushion extends over an area greater than that in which all of the said plurality of speaker units are located in said central backrest area; and a trim cover assembly covering said padding and said sound-conductive cushion.