FR668222A - Improvements to sound reproduction devices - Google Patents

Improvements to sound reproduction devices

Info

Publication number
FR668222A
FR668222A FR668222DA FR668222A FR 668222 A FR668222 A FR 668222A FR 668222D A FR668222D A FR 668222DA FR 668222 A FR668222 A FR 668222A
Authority
FR
France
Prior art keywords
sound reproduction
reproduction devices
devices
sound
reproduction
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)
Inventor
Douglas Heather Johnson
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 filed Critical
Application granted granted Critical
Publication of FR668222A publication Critical patent/FR668222A/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
    • H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/02—Details
    • H04R9/04—Construction, mounting, or centering of coil
    • H04R9/041—Centering
    • H04R9/042—Centering by pressurised air

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
FR668222D 1928-03-15 1929-01-04 Improvements to sound reproduction devices Expired FR668222A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB668222X 1928-03-15

Publications (1)

Publication Number Publication Date
FR668222A true FR668222A (en) 1929-10-29

Family

ID=10491514

Family Applications (1)

Application Number Title Priority Date Filing Date
FR668222D Expired FR668222A (en) 1928-03-15 1929-01-04 Improvements to sound reproduction devices

Country Status (1)

Country Link
FR (1) FR668222A (en)

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