The most noticeable and most obvious difference is in appearance. Spruce is light blonde in color, almost sometimes with a honey/amber tint, while cedar is darker and appears in various shades of brown. Cedar bears a distinct, pleasant odor and is slightly more porous, which may contribute to a faster responding sound. However, there are many more factors that contribute to the overall sound of the guitar. These include internal structure, thickness of material, pattern and shape of the instrument, type of finish, and type of strings. Spruce is the traditional wood that was used for centuries of guitar making. Cedar is much newer on the scene, having become popular and widespread in its use, starting in the mid-1960’s.