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Having read Del's article, I have a question about how soundboards are made.

If I read correctly, the laminated soundboard is flat, and then a crown is formed when the lamination is glued to the curved ribs. When a solid spruce soundboard is made, is the crown formed in the same way, by clamping the flat soundboard to curved ribs, or are solid soundboards carved to a curved crown shape, and then glued to curved ribs to preserve the crown shape?

Until someone more knowledgeable than I chimes in, I believe there are two approaches: rib-crowned and compression-crowned.

Two basic methods are available. Ribs are pre-cut to the desired curve or the panel is dried to a low moisture content before the ribs are glued on which induces a curve as the panel gains moisture. Solid panels are not carved to a curved shape, although I suppose it has been tried.

Curved rib presses can be used on either system to increase or enhance the curve. Any combination you can think of concerning these two system can and probably has been used.

i.e. 1.slightly curved ribs with a moderately dried down panel using a flat (non-curved) rib press

2. Curved rib presses with flat ribs and flat panel using moisture as a further inducement.

3. Flat ribs and curved press not using extreme moisture inducement.

4. Curved ribs, curved press and only slightly dried panel conditions. (My preferred method as the results are more predictable.)

5. Any other combination the manufacturer might think to their benefit.

Only a curved rib option will work with the laminated panel.

Another thing: violins, which have a solid carved spruce top that functions in the same way as a piano soundboard, continue to improve after even hundreds of years of use. Piano soundboards, however, fail after 50 to 100 years of use. Is that because the downbearing on a violin is relatively very small, whereas the downbearing on a piano's soundboard is so great that the wood's fibers are inevitably crushed? Since Mr. Fox indicated that soundboards are not carved, would carving them improve their wearability, or will the amount of downbearing from a piano's strings crush those fibers no matter what?

There was a time when violin repairers replaced tops. It was a fad, like replacing soundboards on pianos. There are plenty of pianos which are older than 50 to 100 years old with original soundboards which would sound like new with just new strings and hammers.

(I suppose that I should add that there were plenty of pianos that did not sound real good when they were new! The design of the soundboard may have had something to do with that, so while the soundboards did not fail, they may not ever have been ideal.)

In general, though, a Stradivarius with a Vuillaume top is no longer considered a Stradivarius.

It's my impression that the general consensus on this forum is that soundboards lasting more than 100 years are a rarity. Is that not correct?

In the violin example there is not only much less downbearing but there is a sound post underneath and supporting the bridge.

There are huge differences in the stress levels of a violin and that of a piano. Compare less than 200 pounds of downbearing for a typical violin to many tons of downbearing in any piano.

I have seen a few pianos that still have some downbearing at 100 years old, but they are rare indeed. I have also seen 30 year old pianos with negative downbearing.

Del,

Thank you for this article and for all the work you have done (and continue to do) in this industry. Your desire to educate has helped me personally more than you know. Your willingness to share over the decades, along with some others of your caliber right here on PW, has IMHO helped to transform the mood at today's PTG conventions. There is more willingness to share, to pursue excellence, to educate, and to work in one accord to help the industry than in any other time in my memory.

Thank you Del et al.

+ google

This would pretty much have to happen by someone building a CAD/CAM system to make one-off laminated soundboards. Front end costs would be massive, and payback questionable. The alternative would be to make them by hand, even more expensive.

What you are suggesting is certainly possible -- and I know it has been discussed -- but I don't know of any manufacturer actually doing it.

ddf

The biggest problem -- in the U.S. at least -- is coming up with the vertical grain surface veneers. They have to be sliced rather than peeled from the log. There are veneer makers in the U.S. that do this but they are mostly set up for hardwoods. They would be happy to do Sitka spruce but one would have to be willing to purchase a car load (give or take).

ddf

Slicing veneers takes a lot of heat and moisture. Could that be adverse for the tonal qualities of the wood?

Veneers can also be sawn, but it's an extremely inefficient use of the wood. You get a lot of sawdust and not much veneer.

So does peeling. But as far as I know it does not affect the tonal qualities of the soundboard panel.

ddf

The most warped, distorted useless soundboard I have ever seen was a Morley laminate. Yuck. The piano that shared the same location and environment did not exhibit any problems like this.

Rotary peeling is how ordinary building plywood is made. It sort of unrolls the growth rings like a roll of paper towels. Shrinkage is greatest around the growth rings. That's why beams with heartwood in them check and split and twist like crazy. That's why the plywood at Home Depot looks like a stack of saddles. I sure hope nobody's even thinking of using rotary peeling for soundboards.

Quarter sawing (or quarter slicing) cuts perpendicular to the growth rings and yields the most stable lumber.

As far as I know there are no manufacturers using peeled veneers for soundboard use.

Peeled veneers are used extensively for pinblock construction and for grand rims.

ddf

there are peeled, sliced and sawed veneers

sawed veeners are the nicest (and the thickest), but they are very rare