Solid (not laminated), premium grade, straight-grained spruce with a minimum of 8 annual growth rings per inch (3 per cm. ) for proven superior tone quality.

由经过严谨挑选的高品质云杉实木（非多层板）木制而成，木纹笔直，每英寸至少有八圈年轮，以提升音质。

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And being made from the straightest of the straight-grained hinoki tree (Japanese cypress), it is a formidably expensive piece of wood.

ECONOMIST: AN ENGINEERING MYSTERY