File:Rice Kellogg loudspeaker 1.jpg
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Summary
| Description |
English: The first moving coil cone loudspeaker, developed by Chester W. Rice and Edward W. Kellogg at General Electric Laboratory in Schenectady, New York in 1925. It is the prototype for almost all modern loudspeakers. It consists of a paper cone attached at the rim to the baffle plate with a very flexible compliant coupling, attached to a light coil of wire (voice coil) in the field of an electromagnet. In this view, the magnet appears to be pulled back so the voice coil is visible. An important part of the invention was Rice and Kellogg's characterization of the acoustic properties of the cone: to have a flat frequency response it had to have a fundamental mode of vibration below 100 Hz and be mounted in a baffle at least 2 feet square. |
| Date | |
| Source | Retrieved January 5, 2015 from http://www.thescreamingend.com/PHONOLAND/rice-kellogg.html Credited to Rice, Chester W.; Kellogg, Edward W. "Notes on the development of a new type of hornless loud speaker" in Journal of the American Institute of Electrical Engineers, A.I.E.E, New York, Vol. 44, No. 9, September 1925, p. 982-991, DOI:10.1109/JAIEE.1925.6534260 |
| Author | Chester W. Rice, Edward W. Kellogg |
| Permission (Reusing this file) |
This 1925 issue of Journal of the American Institute of Electrical Engineers magazine would have the copyright renewed in 1953. Online page scans of the Catalog of Copyright Entries, published by the US Copyright Office can be found here. Search of the Renewals for Periodicals for 1952, 1953, and 1954 show no renewal entries for Journal of the American Institute of Electrical Engineers. Therefore the magazine's copyright was not renewed and it is in the public domain. |
Licensing
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This work is in the public domain because it was published in the United States between 1929 and 1963, and although there may or may not have been a copyright notice, the copyright was not renewed. For further explanation, see Commons:Hirtle chart and the copyright renewal logs. Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 10:36, 5 January 2015 | | 672 × 706 (69 KB) | Chetvorno | User created page with UploadWizard |
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