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FR678950A - Improvements in electrical sound transmission devices - Google Patents

Improvements in electrical sound transmission devices

Info

Publication number
FR678950A
FR678950A FR678950DA FR678950A FR 678950 A FR678950 A FR 678950A FR 678950D A FR678950D A FR 678950DA FR 678950 A FR678950 A FR 678950A
Authority
FR
France
Prior art keywords
transmission devices
sound transmission
electrical sound
electrical
devices
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
Other languages
French (fr)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Thales SA
Original Assignee
CSF Compagnie Generale de Telegraphie sans Fil SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by CSF Compagnie Generale de Telegraphie sans Fil SA filed Critical CSF Compagnie Generale de Telegraphie sans Fil SA
Application granted granted Critical
Publication of FR678950A publication Critical patent/FR678950A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
    • H04R1/40—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers
    • H04R1/406—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers microphones

Landscapes

  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
FR678950D 1928-11-17 1928-11-17 Improvements in electrical sound transmission devices Expired FR678950A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR678950T 1928-11-17

Publications (1)

Publication Number Publication Date
FR678950A true FR678950A (en) 1930-04-07

Family

ID=9021336

Family Applications (1)

Application Number Title Priority Date Filing Date
FR678950D Expired FR678950A (en) 1928-11-17 1928-11-17 Improvements in electrical sound transmission devices

Country Status (1)

Country Link
FR (1) FR678950A (en)

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