sound-light relationship

<<I wanted to ask something about the light sound relationship.
Sure, we know sound has a timbre, but does light have a timbre?
If light does have a timbre, then why do we always see pure colors?>>

I don't think that there is "one" solution or answer to this question. As
you know, there were many attempts to join together light and sound by a
number of composers, most notably by Scriabin, who advocated for a color
organ in his "Prometheus" and who developed his system of correspondence
between the colors and the different pitch keys. In fact, in Russia there is
a whole society devoted to the study of the different types of artistic
attempts at merging sound and color, which resulted in a lot of concerts and
festivals, not to mention publications on the subject. My guess is that
there are _many_ different ways of merging together the sound world and the
light world, and you can't stick to just one system (like Scriabin's or
anyone else's) as the only correct one, but appreciate each one as an
independent artistic statement.

I think that light does have a kind of visual "timbres" and we don't always
see "pure" colors, but sometimes we see pure ones, while at other times we
see "mixed" and "diluted" ones - just like we don't always hear "pure"
sinewaves or "pure" orchestral sounds - sometimes they are pure, and at
other times they are well blended with each other. As your question is sort
of ambiguous, and may even have a humorous connotation to it (though I can't
figure out if this is really the case), this answer is the best one that I
could give at the moment - though the question is an interesting one, and
worth musing and philosophizing on at length, which we can continue to do so
at our leisure.