Let me begin by confessing that I have a personal preference for spruce, although I have a couple of cedar guitars that I love as well. The matter of cedar vs spruce, however, is not as simple as it may appear. Like apples and oranges, there are different varieties-- German spruce, Sitka, Engelman etc. Cedar also has varieties. More importantly, tops vary in quality-- depending upon how well they are cut (perfectly cross-cut) or showing run out, tightens of grain, stiffness across the grain, twist in the tree as it follows the sun, where it grows-- colder harsher climates making for tighter grain. Finally there are cosmetic factors evenness of color, absence of knots, presence of medullar rays etc. All these factors go into grading woods-- Masters, AAA, AA etc. An expert luthier takes all of these factors into consideration in selecting a top, but if there is one criteria that stands above the rest, it is tap tone-- a great top will have a crystalline tone, and one other characteristic, heard by softly running your thumb across the grain-- a sizzle or hiss indicative of how it will perform in high frequencies.
So returning to choice of top, what one wants to pay attention to is clarity of tone-- poor tops whether spruce or cedar will be lacking in clarity-- will be muddy and unresponsive.
Zavaleta's La Casa de Guitarras
James, Zavaleta's La Casa de Guitarras