A physicist's approach to learning a new physical system often begins with some basic things, such as how big, how small, what controls the overall behavior, and so on.  

Discover an overall number to measure the advantages of violin wood: the ratio of density to sound velocity.  

People can intuitively understand that this ratio is very important, by observing, for example, if the panel is heavy, it needs a strong push to push it up.  

However, the panel is not light enough. We want the entire panel to move, not just a small area under the piano code. Therefore, stiffness is also of utmost importance.  

It is interesting to plot the density of various types of wood against the speed of sound.  

The ratio of velocity to density along the straight line originating from the origin is constant: the larger value is considered "good". Balsamu seems to be the chosen material! Of course, we did not recommend this option at all because as mentioned earlier, the static load force of 20 pounds from the piano yard downwards is beyond the strength of Balsamwood.  

However, not far away is the spruce.  

Spruce is the preferred material for almost all instruments with wooden soundboards (piano, guitar, violin, harp), and for the same reason (high rigidity per unit weight), spruce was also the preferred material for airplanes before aluminum could be easily refined (Howard Hughes' famous wooden airplane: spruce goose).  

However, only the violin panel is made of spruce.  

The rest is usually made of curved maple, a hardwood with many patterns.  

The above chart shows that the selection of this material is not based on sound, but on its beauty, perhaps more fundamentally, its strength (the axial tension of the four strings combined exceeds sixty pounds).  

How wood is cut from trees is also important.  

The speed of sound will decrease with the orientation of the fibers and the deviation parallel to the surface.

In fact, not only does the speed of sound decrease, but the rate of vibration attenuation also increases.  

A small deviation of a few degrees can notice its effect.  

Traditional manufacturers have always tended to split wood instead of sawing it. Now we know why.  

Modern mechanical engineers may observe the violin as an example of thin shell technology.  

The violin board starts with a thick wooden block.   

Firstly, determine the shape of the outer side. The curve (known as the arch pattern) is usually copied from an old Italian master's qin.  

Although these arched patterns may appear the same to untrained eyes, their maximum height and curve fullness can vary greatly.