This is a quote from legendary guitar luthier Ervin Somogyi,
“””TONAL POTENTIAL AND TONE CHANGES OVER TIME
It is common knowledge that wooden string instruments — whether they be pianos, mandolins, lutes, or guitars — benefit from being “played in”. Older instruments have tonal qualities of mellowness and smoothness that newer ones lack, the latter often sounding somewhat brittle and harsh in comparison. The analogy of making a stew is often used to describe the quality of transition of a sound which is initially a bit rough, “green” and unsubtle but which gradually blends its elements into something more integrated and smoothly pleasing. In the guitar, also, different woods take different amounts of time for getting “played in”. Why this is so is not fully known but, obviously, it has to do with changes in the cellular and fibrous structures of the woods over time.
Some of these changes have to do with the adaptation of the woods to the stresses of being strung, after possibly centuries of being unencumbered by such forces. A main physical indicator of these changes is seen in the doming in the area behind the bridge which almost all older guitar tops show, but which new ones won’t yet have. Extreme distortion is problematic, but a merely visible amount of it is absolutely normal and even desirable; in fact, guitars which are so overbuilt (through thicknessing, doming, bracing, etc.) or understrung that this distortion of the wood is prevented will never manage to have the developed sound every player wants. The act of actually playing on a guitar, over and above simply stringing and stressing it, seems to have a decisive and accelerating effect on this blending; as with muscles, stretching and “warming up” seems to loosen things up significantly. I make my guitars yielding enough to have some top pull-up, and tell my clients to play them a lot for at least the first few weeks.
Finally, all of the woods described above have a certain tonal potential rather than a fixed quantity of tone. That is, they can be worked with to enhance or suppress certain portions of their potential response spectrum. However, like a plank of wood that can only yield usable pieces shorter than itself when it is cut, and never a longer piece, guitar making woods benefit from the outset only in having the most and best potential tone for their intended use. You can work with any wood to make it sound a lot worse than its potential; but you can only work with it to make it a little, if any, better. Once you’ve figured out what you want your next guitar to sound like, go out and buy the best wood you can find for it.“””