Calcification, feeling like cutting gypsum ": It is a manifestation of a significant change in hardness from the performance parameters of the original material, similar to the calcification of organic matter. This manifestation is a change in the molecular structure of raw materials caused by chemical substances at the microscopic level. This huge change has made wood look less like wood, resulting in various performance manifestations beyond the raw materials of wood. A good voice must come from here. But the material for good sound is no longer wood, but modified wood. It can be certain that in a natural state, this cycle of change takes about three hundred years. In existing examples, ebony, Paleozoic plant fossils, coal, oil, etc. are all actual results of this change. And there are certain rules to follow, for example, the silk gourd fiddle that has survived to this day will undergo calcification in a surface environment with normal oxygen content. Petrochemicals may occur in low oxidation environments. Carbonization may occur in extreme environments. I believe that modern technology can accelerate the completion of this process.

The ideal internal microstructure is not only characterized by good surface hardness, but also by a wall like, tubular, and ray like structure that is both hollow and sturdy. Like a high-rise building, there are numerous rooms inside. The entire building aims to preserve sufficient living space while using lightweight and sturdy materials. The internal structural design, from the beams to the foundation, must comply with the mechanical structure.

The ancient qin is opaque, while the new qin is transparent "is also a result of this physical and chemical change. The density of naturally harvested wood is very low at a moisture content of 12%. It means porous material, and the interior of the new wood is filled with closed cell bubbles and criss crossing wood rays and root canal structures. Only when the internal space of the material is large can it transmit light. Therefore, in the acoustic prime number measurement formula shared by senior forum members, it is necessary to consider whether it is density or apparent density. The unit space volume for calculating density needs to consider not only the volume of external objects, but also the volume of internal space. The volume of the internal space of the material is more meaningful for the sound quality constant. The reason for the opacity is that some substance has entered the walls of these "rooms", increasing the density and strength of the four walls. But it does not increase the overall density of the object. 'Opacity' is not filling the room, but filling the walls. The lack of light transmission here is just a feeling observed by the human eye, and it's not really a matter of iron plates. Only in this way will the overall density remain unchanged and the object will not significantly increase in weight.

Microbial aquatic fungi can transform the closed state of wood cell walls from a dead state to a semi open state. Why semi open? My understanding is that while maintaining the structure of countless' rooms', fungi open the walls of the rooms, allowing a certain substance to be poured into the walls like concrete. And this substance needs to have fluid properties with concrete, high density, and the fluid can be transformed into a solid structure through temperature controlled chemical reactions after entering a designated location.