DE975222C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Loudspeaker arrangement with directional effect
Assignee: Siemens Corp
•
Filing: 1949-04-17
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Granted: 1961-10-05
•
Expires: 1969-04-17
Abstract
No abstract record available.
Inventors
- 👤 Allan Dipl-Ing Dr Darre
- 👤 Heinrich Dipl-Ing Kalusche
- 👤 Friedrich Dr-Ing Spandoeck
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-10-31 08:23
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/20; H04R1/32; H04R1/40; H04R1/403
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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DE934353C
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