Patent US2648969A successfully refreshed from Google Patents.
Patent FR722993A successfully refreshed from Google Patents.
FR722993A
Expired / Lapsed
FR
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Arrangement for acoustic diffusers with bilateral reflection, in particular for electrostatic loudspeakers
Assignee: Hans Vogt
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Filing: 1931-09-18
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Granted: 1932-03-31
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Expires: 1951-09-18
Abstract
No abstract record available.
Inventors
- 👤 Hans Vogt
Bibliographic Details
Application Number
—
Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-11-07 06:54
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/20; H04R1/32; H04R1/34; H04R1/345; H04R19/00; H04R19/02
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References Cited (Backward Citations)
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