The wood will darken with age, but the Formby's or whatever you use will accelerate the aged appearance. It should have no affect on the sound.
Dumb question..but just wondering ?????
I have a pair of speakers that are manufactured by one of the higher end companies and paid extra for the cherry finish. I have used Fornby's oil and or polish on them about once a month or so since I bought them 6 years ago. They have obviously darkened through the years and look absolutely beautiful....So, my question is....does the wood ''age'' as the years go by and add their own sound? I guess my analogy would be guitars and violins get better with age.....does the same hold true for the wood on speakers ?