{ "$schema": "/api/schemas/documents.schema.json", "apiVersion": "1.0.0", "generatedAt": "2026-06-17T23:49:39.838Z", "sourcePath": "src/main/data/docs", "docId": "10.5594-J16623", "document": { "abbrevTitle": "J SMPE", "abbrevTitle$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "abstract": "Of the numerous microphones which have been developed since Bell's original work on the telephone, only two are used extensively in sound recording for motion pictures, namely, the condenser microphone and the carbon microphone. The condenser microphone was first proposed in 1881 but owing to its low sensitivity was limited in its field of usefulness until the development of suitable amplifiers. In 1917 E. C. Wente published an account of the work which he had done on a condenser microphone having a stretched diaphragm and a back plate so designed as to introduce an appreciable amount of air damping. The major portion of the condenser microphones used today in sound recording embody the essential features of the Wente microphone. Marked progress has, however, been made in the design and construction of these instruments with the result that they are not only more sensitive but also more stable. The factors which contribute to this improvement are described in detail in this paper. Recently a number of articles have appeared in the technical press calling attention to certain discrepancies between the conditions under which the thermophone calibration of the condenser microphone is made and those which exist in the studio. The nature of these discrepancies and their bearing on the use of the microphone are discussed. Microphones in which the sound pressure on the diaphragm produces changes in the electrical resistance of a mass of carbon granules interposed between two electrode surfaces have been used commercially since the early days of the telephone. In recent years the faithfulness of the reproduction obtained with the carbon microphone has been materially improved by the introduction of an air damped, stretched diaphragm and a push-pull arrangement of two carbon elements. This instrument is finding extensive use in sound recording and reproduction fields where carbon noise is not an important factor. The outstanding design features of the push-pull carbon microphone are described in this paper and suggestions made as to the precautions to be taken in its use if the best quality, maximum life, etc., are to be obtained.", "abstract$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "articleType": "research-article", "articleType$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "authors": [ "W. C. Jones" ], "authors$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "copyright": { "holder": "Society of Motion Picture and Television Engineers, Inc.", "holder$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "year": "1931", "year$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" } }, "copyright$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "docId": "10.5594-J16623", "docId$meta": { "confidence": "high", "note": "Derived from DOI 10.5594/J16623", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "docLabel": "Journal of the Society of Motion Picture Engineers ( Volume: 16, Issue: 1, January 1931)", "docLabel$meta": { "confidence": "medium", "note": "Composed from venue title, volume/issue and date", "source": "inferred", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "docTitle": "Condenser and Carbon Microphones—Their Construction and use", "docTitle$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "docType": "Journal Article", "docType$meta": { "confidence": "high", "note": "NLM
— SMPTE journal paper", "source": "inferred", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "doi": "10.5594/J16623", "doi$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "href": "https://doi.org/10.5594/J16623", "href$meta": { "confidence": "high", "note": "Constructed from DOI 10.5594/J16623", "source": "inferred", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "issn": { "print": "0097-5834", "print$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" } }, "issn$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "journalAcronym": "MIJR", "journalAcronym$meta": { "confidence": "high", "note": "Parsed from journal_metadata XML (_source/SMPTE/APTARA/DL Project Files/08182015 BACKFILE JOURNAL FRESH/smptej_16_1/MIJR15Vol16No1.xml)", "source": "parsed", "updated": "2026-06-17T00:17:09.425Z", "version": "smpte-journal-issue-xml@v1" }, "number": "1", "number$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "pages": "3–22", "pages$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "publicationDate": "1931-01-01", "publicationDate$meta": { "confidence": "high", "note": "Day absent in NLM source — padded to 01", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "publisher": "SMPTE", "publisher$meta": { "confidence": "high", "note": "Normalised to registry \"SMPTE\" convention from NLM publisher-name (The Society of Motion Picture and Television Engineers)", "source": "inferred", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "publisherLocation": { "city": "White Plains, NY", "city$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "country": "USA", "country$meta": { "confidence": "high", "note": "Parsed from journal_metadata XML (_source/SMPTE/APTARA/DL Project Files/08182015 BACKFILE JOURNAL FRESH/smptej_16_1/MIJR15Vol16No1.xml)", "source": "parsed", "updated": "2026-06-17T00:17:09.425Z", "version": "smpte-journal-issue-xml@v1" } }, "publisherLocation$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" }, "status": { "active": true, "active$meta": { "confidence": "medium", "note": "No explicit status in NLM source — journal papers default active", "source": "inferred", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" } }, "volume": "16", "volume$meta": { "confidence": "high", "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J16623.xml)", "source": "parsed", "updated": "2026-05-22T21:44:19.125Z", "version": "smpte-journal-article-nlm@v1" } } }