BE474660A - - Google Patents

Info

Publication number
BE474660A
BE474660A BE474660DA BE474660A BE 474660 A BE474660 A BE 474660A BE 474660D A BE474660D A BE 474660DA BE 474660 A BE474660 A BE 474660A
Authority
BE
Belgium
Application number
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.)
Publication of BE474660A publication Critical patent/BE474660A/xx

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
    • H04R1/34—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means
    • H04R1/345—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means for loudspeakers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
    • H04M1/6033—Substation equipment, e.g. for use by subscribers including speech amplifiers for providing handsfree use or a loudspeaker mode in telephone sets

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
BE474660D 1946-08-17 BE474660A (no)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US691279A US2483231A (en) 1946-08-17 1946-08-17 Loud-speaking telephone set with low acoustic coupling

Publications (1)

Publication Number Publication Date
BE474660A true BE474660A (no)

Family

ID=24775892

Family Applications (1)

Application Number Title Priority Date Filing Date
BE474660D BE474660A (no) 1946-08-17

Country Status (3)

Country Link
US (1) US2483231A (no)
BE (1) BE474660A (no)
FR (1) FR949759A (no)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2580439A (en) * 1949-09-07 1952-01-01 Bell Telephone Labor Inc Directional acoustic system
US3069508A (en) * 1958-05-02 1962-12-18 Ericsson Telefon Ab L M Telephone instrument
WO2011042019A1 (en) * 2009-10-07 2011-04-14 Sl Audio A/S Dipole loudspeaker with diffuse rear radiation

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2114680A (en) * 1934-12-24 1938-04-19 Rca Corp System for the reproduction of sound
FR856727A (fr) * 1938-06-24 1940-08-03 Telefunken Gmbh Système permettant d'éviter les réactions acoustiques dans les installations de diffusion de parole
US2177769A (en) * 1938-12-24 1939-10-31 Frank I Du Frane Company Inc Loud-speaking intercommunicating system
US2208160A (en) * 1939-10-19 1940-07-16 Harold J Mccreary Communication system
US2381174A (en) * 1942-11-16 1945-08-07 Brush Dev Co Communication system
US2385279A (en) * 1943-01-27 1945-09-18 Bell Telephone Labor Inc Distant talking loud-speaker telephone system

Also Published As

Publication number Publication date
FR949759A (fr) 1949-09-08
US2483231A (en) 1949-09-27

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