Class 369/158 - Acoustical tone arm

Subclass of Class 369 - Dynamic information storage or retrieval
Definition: Subject matter limited to a tone arm with acoustical coupling
No. of patents: 2
Last issue date: 04/17/2007

Number	Title	Issue Date
7204342	Sound focus speaker of gas-filled sound lens attachment type A sound focus speaker adopting a gas-filled sound lens enhances efficiency of transferring sound from a source to target area and of protecting a spread of transferred sound. The sound focus speaker includes a gas-filled sound lens, sound sources for generating soun...	04/17/2007
4261580	Arm pipe for record player tonearms An arm pipe for a record player tonearm comprises a composite material essentially consisting of a thermoplastic resin and graphite powder. The composite material is prepared by kneading the components, rolled to impart a degree of orientation to the grap...	04/14/1981

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