Hello Ethan kindly invited me to post to this board after I asked him a question on Youtube: why are the walls in most studios made of wood? Does it make the sound better? How is it different than, let's say, gypsum board or plaster?
I have to note, that I am not a recording engineer, nor a real musician - I've made some recordings and played with Fruity Loops as an amateur. Acoustics are my general interest.
I'm sure some people believe that wood sounds different than drywall or other common reflecting surfaces, but I assessed this a few years ago and concluded that any differences are minor and occur only at the very highest frequencies: