A frame for a speaker device has an annular outer peripheral portion. The outer peripheral portion includes plural wall portions concentrically formed. An end surface of the wall portion on an inner circumferential side of the outer peripheral portion is formed at a position recessed as compared with an end surface of the wall portion on an outer circumferential side in a direction of a central axis of the outer peripheral portion.

 
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> Loudspeaker with progressively damped acoustical chamber

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