Almost all violin back plates feature tiger-stripe-like patterns that shift in refraction with changes in viewing angle, dazzling to the point of being irresistible. How do these tiger-stripe patterns come about, and what is their function? The back plates of violins are mostly made of maple wood. During its growth, to adapt to changes in the external environment, the maple tree develops wrinkle-like textures at the bends of its trunk. Such textures occur not only in maple, a broadleaf tree species, but also in pine or fir, which are coniferous tree species. A tree's natural tendency is to grow straight upward, but when the ground is uneven or it grows on a slope, the trunk becomes curved. The cells within the trunk grow unevenly in the uphill and downhill directions to support the branches and leaves above, with one side being compressed and the other stretched. This force of nature is what causes the tiger-stripe patterns. Maple trees with tiger stripes behave differently from ordinary wood during the lumbering process. Their cellular structure is not uniform, causing them to grip the saw during cutting and deform during drying. Originally square timber becomes skewed after drying. If maple wood that has not been thoroughly dried is used to make violins, problems will arise. As previously mentioned, tiger stripes are formed by irregular cell growth, much like human wrinkles, varying in depth and size. Deep and large tiger stripes look very beautiful and charming on a finished violin, with some people even specifically seeking out such instruments. From the buyer's perspective, this is understandable, but violin makers may have a different viewpoint. The areas where maple trees develop wrinkles (tiger stripes) are mostly close to the tree's surface (bark). The closer to the heartwood, the lighter the tiger-stripe patterns become, with the wood darkening in color and becoming denser in texture. Only such dense material can be used to make thinner back plates, which have an absolute advantage in vibration and can produce louder sounds. In terms of aesthetics and functionality (producing louder sounds), maple cannot actually achieve both simultaneously. Apart from maple, cherry wood and mahogany (translated by the author for reference only) can also be used to make violin back plates without any issues in sound production. The author has seen some guqins still in use today, some of which still play the leading role in performances. Their powerful sound is like a cannon roaring during a performance. Despite their unimpressive and plain appearance, which might even seem shabby, they take on a pale yellow hue (the original color of the lacquer) after the original dye fades, and their backboards lack conspicuous, splendid tiger-stripe patterns. Nevertheless, they occupy the most crucial position in performances. It appears that the maker struggled with the trade-off between aesthetics and functionality when selecting material for the backboard. After a centuries-old maple tree is felled, it undergoes storage (in water), cutting, drying (a special drying process), sorting, and is finally cut into the dimensions required for guqin making. Only about five percent of the entire maple tree may possess beautiful tiger-stripe patterns, with the rest being plain maple wood without any grain.

There are wavy wrinkles on the tree-like surface, indicating that the internal tissue exhibits a tiger-stripe pattern.

Upon enlarging the wood in hand, we can clearly see the tiger-stripe pattern.

The maple wood on the left is light-colored with a looser texture, while the one on the right is darker with a harder texture.