File:Bell telephone magazine (1922) (14775880373).jpg

Identifier: bellvol25telephonemag00amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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power, and there-fore It had to be designed for thehighest possible efliciency. The powerfrom the microphone had to be sufl^i-clent to provide electrical Impulses ofenough strength to produce the re- quired volume when the electric cur-rent was translated into sound at thereceiver. Arnolds high-vacuum tube amplifiermade It possible to sacrifice efficiencyfor the sake of quality. Accordingly,Wente concentrated upon a micro-phone which would give uniform re-sponse at the various pitches In theaudible range. His thermophone per-mitted quantitative measurements ateach Individual pitch. By 1916 he haddeveloped the condenser microphone.It gave uniform response up to morethan 15,000 cycles, and left little to bedesired from the standpoint of qual-ity. Both his thermophone and con-denser microphone were adopted asstandard by the International Refer-ence System for Telephony located InParis. For his condenser microphonehe received the John Price Wetherellmedal of the Franklin Institute. In an
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E. C. Wente. Hiscondenser microphoneivas one of the founda-tion stones on whichsound motion pictureswere built 90 Bell Telephone Magazine SUMMER article published in the Physical Re-view in 1917, Wente pointed out theadvantages of his condenser micro-phone for recording sound upon film. Accomplishtyients of Four Years During Wentes early research, therecording of sound was receiving afresh impetus from the success andfuture possibilities of the high-vacuumtube. In June 1915, Arnold suggestedmaking phonograph records with ahigh-quality transmitter anci amplifier,pointing out the exceptional resultswhich had been obtained by use of theFrederick transmitter in conjunctionwith a vacuum-tube amplifier duringtransmission tests between Denverand New York. Crandall and Kranzhad used their electrical reproducerexperimentally in 1914. By 1915,superior electrical reproducers werein use with phonograph records, butthe records themselves had not beenmade electrically; in other words, notby a metho

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