Wood grain and sonic quality

[Steve-o]

This may be an old topic, but I was wondering what wood grain orientation is preferred with respect to sound quality (tone, volume, projection, sustain) - flat sawn or quarter sawn? Or are the differences subtle?

[billhay4]

Are you speaking of the top or back?
Tops are quartersawn for the most part. Backs are optional.
Sound differences are affected by other factors much much more than the sawing orientation of the back.
Bill

[sunburst]

I prefer quartered wood for tops, backs, sides, fingerboards, and necks.

I don't know of anyone who uses anything other than quartered wood for tops, but some use and even prefer slab cut wood for sides, backs, and necks.

I don't know of any evidence, other than anecdotal, that there is any difference in sound attributable to slab cut wood in the sides and back as opposed to quartered wood, and I don't believe there is any real difference in sound between the two.
Quartered wood is more stable dimensionally so it moves less with relative humidity changes, and that is reason enough for me to prefer it to the point that I only use slab cut wood when I have to because of a customer request for quilted or bird's eye figure or something like that.
Wood that is more stable (quartered) moves less and puts the structure of the instrument under less stress, so the instrument is less likely to be damaged if it encounters changes in relative humidity. Over time, repeated wood movement can affect the integrity of glue joints, and the wood itself, if the movement is restrained like it is in a glued-together instrument. A relatively common problem in old Gibson mandolins, particularly F2s and F4s it seems, is separation of the slab cut back from the head block and/or tail block resulting from back shrinkage sheering the cross-grain glue joint. I figure an instrument with better integrity is likely to sound better in the long run.

[Steve-o]

Are you speaking of the top or back?

Bill, I was speaking of backs. John, thanks for your comments about dimensional stability. That certainly makes sense. I have heard that, sonically, the density of the wood is more important than the grain.
- Steve

[sunburst]

I'd say density, stiffness, and damping are relatively important, grain direction...I doubt there's any difference in sound.