The wood material of the rear housing of the earphones makes a difference in the sound produced by the earphone drivers.
This is simply put, it is similar to the different materials used for the shells of drums.
There are differences in sound depending on the type of wood, mainly due to the following.
Specific gravity, density.
Hardness, Young’s modulus.
Material damping ratio.
Oil content.
Material permeability.
However, the specific gravity and Young’s modulus of wood vary slightly depending on the institution and method of measurement.
In addition, there are individual differences in wood.
Since wood is a natural material, no two pieces are exactly alike.
These factors make it very difficult to define the sound of wood.
First of all, it should be noted that wood has individual differences and we cannot clearly quantify its specific gravity or Young’s modulus.
After understanding this, we should know the “sound tendency of wood” which can be derived from average values and so on.