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アイテム
Ensuigata-Rappa no Onkyogakutekino Seisitu ni tuite.
https://jaxa.repo.nii.ac.jp/records/35560
https://jaxa.repo.nii.ac.jp/records/35560e4862d2d-ff48-46ea-9136-71235f047936
| 名前 / ファイル | ライセンス | アクション |
|---|---|---|
SA4225795.pdf (680.4 kB)
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| Item type | 紀要論文 / Departmental Bulletin Paper(1) | |||||||
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| 公開日 | 2015-03-26 | |||||||
| タイトル | ||||||||
| タイトル | Ensuigata-Rappa no Onkyogakutekino Seisitu ni tuite. | |||||||
| 言語 | ||||||||
| 言語 | jpn | |||||||
| 資源タイプ | ||||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_6501 | |||||||
| 資源タイプ | departmental bulletin paper | |||||||
| その他のタイトル（英） | ||||||||
| その他のタイトル | On the Acoustical Properties of Conical Horns. | |||||||
| 著者 |
SATO, Kozi
× SATO, Kozi
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| 出版者 | ||||||||
| 出版者 | 東京帝國大學航空研究所 | |||||||
| 出版者（英） | ||||||||
| 出版者 | Aeronautical Research Institute, Tokyo Imperial University | |||||||
| 書誌情報 |
東京帝國大學航空研究所報告 en : Report of Aeronautical Research Institute, Tokyo Imperial University 巻 4, 号 42, p. 1-19, 発行日 1928-06 |
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| 抄録（英） | ||||||||
| 内容記述タイプ | Other | |||||||
| 内容記述 | The intensity of sound as received through a conical horn with its axis set at different angles θ to the ray of sound, was measured by the Rayleigh disc. The most remarkable of the results is that the distribution of the sound intensity as function of the angle θ mainly depends upon the wave-length (or the frequency) of the sound, and only slightly upon the geometrical shape of the conical horn if the diameter of the opening be the same. If the wave-length of the sound be short enough as compared to the diameter of the opening, the sound energy is considerable only for small values of θ. On the contrary, if the wave-length be long compared to the diameter, the sound energy is nearly equal for different values of θ. These relations can be seen from the experimental results shown in Fig. 4 a, b, where the abscissae are the angles (θ) between the axis of the horn and the line connecting the source with the center of the opening of the horn and the ordinate, the intensity of sound, λ being the wave-length. Two different shapes of the horn A and B were used in the experiments. Their dimensions are shown at the corner in the corresponding figures a and b. For example, in Fig. 4a, the intensity at θ=30°is, for λ=100cm., about 80% of that at θ=0°, while for λ=10cm., it is practically nil. From this we see that, when we wish to get a faithful record of a sound, using the conical horn as a collector, the source must be set in front of the horn (θ=0°), otherwise all higher overtones, will be missed and an entirely different sound from the original one will be recorded. This precaution is especially necessary when the sources of sound are distributed in a large space as in an orchestra. By the reciprocal theorem, we can interchange the positions of the source and the measuring point and infer the following relations. If the wave-length be short, the energy of the sound given out through a conical horn propagates mainly along its axis as light does. On the contrary, if the wave-length be long, it propagates nearly uniformly in all directions. It is remarkable that the sound field due to the conical horn thus depends upon the frequency of the source. Therefore if a complex sound with many overtones is sent through a conical horn and observed at a position deviating from its axis, the ratios of the intensities of the overtones received will be different from those of the original ones, in other words the sound will be distorted. This fact is easily observed in using a megaphone or a loud speaker. The distortion of sound by the conical horn is more due to the fact that the distribution of sound intensity is different according to the wave-length or the frequency than to the resonance as has been mostly believed. From the smallness of the dependence of the results on the geometrical shape of a conical horn, we may expect that the above results are applicable in the main to the exponential horn as well. This paper also gives a suggestion regarding the practical problem of a horn to be used as a collector or distributor of sound, as to its favourable shape and precautions in practice. | |||||||
| 書誌レコードID | ||||||||
| 収録物識別子タイプ | NCID | |||||||
| 収録物識別子 | AA00387631 | |||||||
| 資料番号 | ||||||||
| 内容記述タイプ | Other | |||||||
| 内容記述 | 資料番号: SA4225795000 | |||||||
