Claravox walnut and sunlight fade / preventative maintenance

[snapeye]

Hi. We all know walnut is gorgeous but usually fades in sunlight pretty fast. Do you have any information on how this Claravox wood specifically was treated/oiled/varnished/etc. if at all? Just need to plan around curtains and possible window UV film, maybe a linseed oil treatment on the Claravox. My music room gets a lot of sunlight. Thank you.