• Title/Summary/Keyword: European spruce

Search Result 4, Processing Time 0.019 seconds

Effect of specific gravity and annual ring width on the acoustical properties of European lumber used in violin making (유럽산 바이올린 용재의 비중과 년륜폭이 소재의 음향적 성질에 미치는 영향)

  • 정우양;홍병화
    • Journal of the Korea Furniture Society
    • /
    • v.10 no.1
    • /
    • pp.57-63
    • /
    • 1999
  • This study was carried out to analyze the relationship between basic physical properties and acoustical characteristics of imported violin wood and to offer the information on raw material procurement and incoming-material quality control to domestic violin makers which have purchased most raw materials from European exporting countries at high expense. Equilibrium moisture content of European spruce with lower specific gravity after the prolonged storage was rather higher than that of European maple with higher specific gravity. The specific gravity of spruce increased with decreasing annual ring width, however, that of narrower annual ring. Increasement in specific gravity enhanced the dynamic Young's modulus of both wood species, but influenced the vibration energy loss by internal friction differently between two species. For dynamic MOE, qurater-sawn spruce was higher than the flat-sawn, but maple showed the reverse directional characteristics. Consequently, it would be well for violin makers to establish the standard for materials and quality control system to assure the quality of their violin products.

  • PDF

Studies on the Vibrational Modal Analysis of Solid Woods for the Violin Making - Part 1. Effect of Cutting Direction and Density on Resonant Frequency of Woods (바이올린용(用) 소재(素材)의 진동모드 해석(解析)에 관한 연구사 - 제1보. 절삭방향 및 밀도에 따른 공진 주파수의 변화)

  • Chung, Woo-Yang;Park, Sun-Haeng
    • Journal of the Korean Wood Science and Technology
    • /
    • v.27 no.3
    • /
    • pp.1-6
    • /
    • 1999
  • European spruce and maple were to be estimated as raw material of violin family instruments with linear modal analysis to provide the information data for the design of their bodies. Wood specimens cut in different direction were excited by impact hammer to measure the resonant frequency with typical vibrational modes. In spite of lower density than maple, European spruce showed the excellent acoustical properties with higher resonant frequency. And edge-grained spruce had more even frequencies than flat-grained ones to be more acceptable as front plate of violin. Resonant frequency was positively correlated with wood density of each specimen and the coefficients of edge-grained specimens were higher than those of flat-grained specimens of both wood species.

  • PDF

Studies on the Vibrational Modal Analysis of Solid Woods for making the Violin - Part 2. The effects of coating materials on the resonant frequency of European spruce and maple

  • Chung, Woo-Yang;Park, Sun-Haeng
    • Journal of the Korea Furniture Society
    • /
    • v.11 no.1
    • /
    • pp.45-51
    • /
    • 2000
  • It was thought that the stiffness of a coated specimen became lower than that of the solid wood because the stiffness of the dried film of coating material is lower than that of the solid wood. The authors were trying to compare the effect of lacquer varnish and rhus lacquer on the resonant frequency of the solid woods for the violin, spruce and maple. Vibration modal shape of coated specimens were same to those of solid woods, but the frequency became lower at each mode as were expected regardless of coat. frequency decrement of coated specimen was getting larger at upper mode in both European violin woods, however, rhus lacquer coated spruce specimens were less affected than lacquer varnish coated specimens.

  • PDF

Ecological Investigations on the Managed Forests in Northwestern Europe and Tree Seed-Orchard System (북구(北歐)의 우량임분(優良林分)의 생태(生態) 및 채종원(採種園) 체계(體系)에 관(關)한 연구(硏究))

  • Kim, Chi Moon
    • Korean Journal of Agricultural Science
    • /
    • v.9 no.1
    • /
    • pp.239-249
    • /
    • 1982
  • The outlines of superior stands, including species mixed, age classes, canopies, and ecological conditions of the stands, were examined in the forests of west Germany, Sweden, and Netherland. The establishment schemes of tree seed orchards for the production of high genetic quality seed were also investigated in the present study. 1. The meteorological conditions, abundant in precipitation and high in relative humidity, prove it to be oceanic climate characteristics in the Scandinavia located in high latitude and north-western part of Europe. The photo periodical characteristics following to day-length and the frost times determine the patterns of tree growth and distribution as well as the tree adaptability due to bud-setting and bud-flushing in Sweden forest. 2. The European forests are generally characterized by dense multistoried forest type composed of upper stories of tall tree species such as Norway spruce, fir, Scots pine and beech, lower stories of shade tolerant poles and saplings of spruce, fir, beech, and floor vegetations covered with birch, oak and hornbeam etc. 3. The single tree selection method and group shelterwood method are commonly applied for silvicultural system but shelterwood method and clearcutting method practiced partially in limited area. Badischer Femelschlagbetrieb and Bayerischer Femelschlagbetrieb are popularized to the regeneration of Schwarzwald but selection method applied in part. 4. Tree cuttings are properly limited so as not to exceed annual increment volume for the sustained yield and the preservation of ecosystem in European forest management. Land preservation and recreation function are more interested with the promotion of wood production in the forest management. 5. Careful attentions are paid to the reforestation of the introduced exotic species, such as Douglas-fir, red oak, pines from America, Japanese larch, Italian poplar etc., with concern against the insect and pest damage, and the meteorological damage. 6. Some intensive studies on tree improvement, such as selection of plus tree, selection of plus stand for seed collection, provenance trial, progeny test of clone, hybrid seed orchard for clone complexing, are performed in the countries and the great part of the seed required for reforestation are supplied from the seed orchard established in Sweden and Netherland.

  • PDF