What makes a wood superior seeing as there is no single sound or tone we all agree upon as being the perfect one? The answer seems elusive, however, not impossible! We can base the term on facts rather than opinion.
First and foremost are the resonant properties of the wood. Resonance is what generates the sound from a guitar along with all the other tonal qualities every perceptive guitarist is searching for. This includes response, sound projection, sustain, harmonic dynamics, complexity of overtones and balance throughout the range of pitch.
Generally speaking, the better all of these properties are, the better the sound/tone... and it is the species of wood that determines the vast majority of these qualities. Scientifically speaking, for wood to resonate perfectly it must have a cell structure conducive to transferring waveform energy with the least resistance so as not to diminish the sound wave. It must also have low moisture content as moisture will interrupt the optimum waveform.
Another consideration is the age of the wood and more specifically, the state of the resin (pitch). The conventional wisdom is that aged wood will make a better sounding guitar than younger wood, which by experience we fully agree with. In aged wood, the resin is crystallizing or has fully crystallized and will present a slightly clearer tone than if the resin is still fluid.
Resin in young wood has not crystallized and moves and re-adjusts its position as the instrument is played. This results in less resistance to the waveform due to the resin being re-arranged by the waveform to allow the best resonance and in the end, the best sounding guitar.
This same condition can affect a guitar that is stored in a case for some time without being played. When eventually pulled out of its case, it just does not sound as good as it did before. After a fair amount of playtime, it starts sounding great again due to the repositioning of the resin within the wood.
As a conclusion to all these factors, our aim is to help musicians choose their instrument according to the potential tone from the tone-woods - not on how a wood species might look.
Music is sound and tone. All the differences in tone are only a matter of species!