• 한국가구학회지
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• 제16권1호
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• pp.17-23
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• 2005

European maple is famous for the optimum solid wood for making bridge which is the most important part in violin acoustics. This study was carried out to investigate the variation of main features, i. e. annual ring width and cutting direction of costly imported violin bridge blanks and to examine the effect of these features of the blanks on the vibrational characteristics of bridge blanks. Imported violin bridge blanks had somewhat large variation in major macroscopical and physical properties and there was little relationship between annual ring density and weight of maple blanks. Resonant frequency of violin bridge blanks had some positive correlation with weight, however, damping having negative relationship with frequency was seldom affected by any physical properties of the maple blanks. Deviation from the radial cutting of tail side(ray direction from top toward feet on the edge of bridge blank) lowered the resonant frequency. Consequently, weight and ray direction should be taken for the critical quality decisive factors(QDF) of incoming bridge blanks by not only inspectors also luthiers who tune the bridge by shaping and are responsible for the final timbre quality of this complicate instrument.

• 한국가구학회지
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• 제12권1호
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• pp.47-55
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• 2001

Violin bridge blank cut from maple wood with good quality has typical pattern of the radial direction in the side edge with minimal dispersion. This experimental study was designed and carried out to examine the effect of the physical and macroscopical characteristics on the compressive creep of violin bridge blank which had been imported from European manufacturer. This research arose from the idea that the maple solid wood with heterogeneous wood density and ray direction in the side edge would have uneven rheological property of violin bridge blank which is supposed to be pressed by the tension of strings. Experimentally, the compressive creep of bridge blank became smaller with the higher density of imported maple wood and showed clear density-dependence for the duration of load under the string tension of 5 kgf. Every bridge blank showed the behavior of primary creep stage(stress stabilization) having logarithmic regression creep curve with high correlation coefficient under the designed stress level. Even though the relationship between compressive creep and ray direction on the side edge of bridge was not so clear contrary to expectation, we could conclude that wood density and ray direction should be the quality decisive factors affecting the acoustical characteristics and performance of the bridge, the core member of violin-family bow instruments.

• 한국음향학회지
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• 제9권3호
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• pp.11-23
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• 1990

奚琴 音質의 音響學的 特性을 조사하기 위해 奚琴音의 파워스펙트럼과 時間波形을 FFT Analyzer를 이용하여 분석하였다. 奚琴絃의 張力과 遠山(bridge)의 위치, 腹板(top plate)의 두께등을 변화시키면서 분석을 하였다. 실험에 의하여 다음과 같은 결론을 얻었다. 腹板의 共振周波數가 絃의 基音의 周波數보다 높기 때문에, 基音의 音壓보다 腹板의 共振周波數 부근의 上音들의 音壓이 더 큼을 알았다. 絃의 張力이 강할 때와 遠山이 腹板의 중앙에 위치하였을 때가 音質이 보다 우수하였다. 奚琴 遊絃의 inharmonicity 계수는 0.049 cents/$n^2$이었다. 5kHz 이상의 上音은 발견할 수 없었으며, 奚琴의 inharmonicity가 violin의 inharmonicity보다 큰 값을 나타내었는데 이를 통해 奚琴음의 明瞭度와 豊富性이 부족하다는 것을 알 수 있었다. 奚琴筒의 共振周波數(MAR)와 腹板의 共振周波數(MWR)의 周波數比는 1 octave 정도일 때 奚琴이 가장 좋은 음색을 갖는다는 것을 밝혔으며 이때 腹板의 두께는 4.5mm 정도이다.