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Laminated soundboards

Posted By: Del

Laminated soundboards - 09/26/15 01:51 AM

Those who have read my various missives on how piano soundboards work will be aware that I have long advocated the use of high-performance, engineered laminated soundboard systems especially in smaller low- to mid-priced pianos.

The Fall, 2015 issue of the “Piano Buyer Magazine” is now available online. In this issue there is an article of mine titled The Benefits of Laminated Soundboards. It can be found on page 51 and this link should take you to it:
http://www.pianobuyer.com/fall15/49.html

As always, questions and comments are welcome.

ddf
Posted By: Rickster

Re: Laminated soundboards - 09/26/15 02:54 AM

Excellent article, Del!

I was not aware that laminated soundboard technology dated back as far as it did... a great bit of history included in your article.

Here is a post I made in Larry Fine's thread announcing the new edition of Piano Buyer...

In my view, anything Del Fandrich writes/says... is like the old "E.F. Hutton" commercial used to say, "When E. F. Hutton speaks, everybody listens"; when Del Fandrich speaks, everybody listens! (At least I do smile ).

I owned one of the Kimball Viennese model grands, with the laminated soundboard, (the 5'8" model) and that piano held a tuning better than any piano I've owned to date (and I pounded it pretty hard). So, even without reading the article, I'm sure that tuning stability is one of the benefits of using the laminated soundboard.

I'll look forward to reading that article (which I just did smile ).

Best regards,

Rick
Posted By: Olek

Re: Laminated soundboards - 09/26/15 10:49 AM

Del, are not laminated panels heavier?

I find they deliver a lit of power, at the expense of tone variability.

I wonder how much build in stress can be obtained, as I see no other way to fight the inertia of laminated panels.

The technology certainly did evolve, allowing nicer results.

That seem to be the top of the spectrum thar is damped, but now, this can be compensated by the use of a wire that produce more partials, I suppose (thinking of Pitthan wire here)

Regards
Posted By: prout

Re: Laminated soundboards - 09/26/15 12:29 PM

Thanks Del, for an informative and well written article.

Did you find, using the B&K equipment, a characteristic difference in the modes of the laminated soundboard versus solid: first mode resonant frequency, magnitude of vertical motion, bridge/soundboard impedance across the compass, for example, or was it mostly the same or just an overall change in the magnitude of the variables?

Cheers,

prout
Posted By: Roy123

Re: Laminated soundboards - 09/26/15 03:26 PM

Del, it's common for soundboards to be tapered on some of their edges. How does one modify the design of a soundboard and ribs to allow for the fact that laminated boards aren't tapered?
Posted By: Del

Re: Laminated soundboards - 09/26/15 03:55 PM

Originally Posted by Olek
Del, are not laminated panels heavier?

Just like a solid panel that depends on the materials used and its construction. A 7.5 mm laminated spruce panel will weigh the same as a 7.5 mm solid panel. (Assuming variations for the character of individual pieces of wood.)


Quote
I find they deliver a lit of power, at the expense of tone variability.

I find that some pianos with solid panels "deliver a [lot] of power, at the expense of tone variability." In other words, just like solid panels have to be designed and constructed for a desired sound, so do laminated panels. Not all solid panels are the same. Neither are all laminated panels.


Quote
I wonder how much build in stress can be obtained, as I see no other way to fight the inertia of laminated panels.

Why fight inertia? Leave out what you don't want. Inertia in a soundboard system is the aggregate of all of its various parts and components. That includes the bridges, the panel, the screws, the bridge pins, the ribs, the finish material, etc.


Quote
The technology certainly did evolve, allowing nicer results.

That seem to be the top of the spectrum thar is damped, but now, this can be compensated by the use of a wire that produce more partials, I suppose (thinking of Pitthan wire here)

Again, the spectrum produced by a piano with either soundboard system is a function of its overall design and construction. Not just one thing like the construction of the soundboard panel.

Blanket statements like, "...the top of the spectrum that is damped," are no longer relevant.

ddf
Posted By: Ed A. Hall

Re: Laminated soundboards - 09/26/15 03:56 PM

Del,

Do you envision laminated soundboards someday being made available for piano rebuilders to install in pianos needing rebuilding? There are so many older pianos with defective soundboards that so often don't get replaced for various reasons. I would think that there would be a market for these soundboards if made available to the piano rebuilding community.

Ed
Posted By: Del

Re: Laminated soundboards - 09/26/15 03:57 PM

Originally Posted by prout
Thanks Del, for an informative and well written article.

Did you find, using the B&K equipment, a characteristic difference in the modes of the laminated soundboard versus solid: first mode resonant frequency, magnitude of vertical motion, bridge/soundboard impedance across the compass, for example, or was it mostly the same or just an overall change in the magnitude of the variables?

Nothing that jumped out. But these were very limited tests.

ddf
Posted By: Del

Re: Laminated soundboards - 09/26/15 04:23 PM

Originally Posted by Roy123
Del, it's common for soundboards to be tapered on some of their edges. How does one modify the design of a soundboard and ribs to allow for the fact that laminated boards aren't tapered?

Solid panels are often tapered on some of their edges. Steinway soundboard panels—and the many that have been copied from Steinway construction—are typically diaphragmed; i.e., they are tapered all around the parameter of the panel. In the treble this tapering contributes to the (relatively) rapid rate of the collapse of the system—i.e., the killer octave and can be counter-productive. That said, soundboard panels—both solid and laminated—can also be too thick in the treble. That is easily dealt with using a solid panel. Simply plane it down. It is not so easily done with laminated panels. Typically a laminated soundboard panel will be sized to accommodate the treble.

Thinning the sides of a solid soundboard panel makes little difference as spruce is already quite flexible in the perpendicular-to-grain direction. The bridges are located rather far from the rim where the soundboard panel is supported so neither panel thickness or flexibility is much of an issue. As well, the motion of the bridges at the middle frequencies is [very[/i] small..

This leaves the bass. In longer pianos just keeping the bass bridge a reasonable distance from the rim provides adequate mobility. In shorter pianos some heroics are called for. The easiest of these is to simply float the lower parameter of panel.

ddf
Posted By: Del

Re: Laminated soundboards - 09/26/15 04:25 PM

Originally Posted by Ed A. Hall
Del,

Do you envision laminated soundboards someday being made available for piano rebuilders to install in pianos needing rebuilding? There are so many older pianos with defective soundboards that so often don't get replaced for various reasons. I would think that there would be a market for these soundboards if made available to the piano rebuilding community.

I would think so as well. I don't see it happening any time soon, however.

ddf
Posted By: chopin_r_us

Re: Laminated soundboards - 09/26/15 04:28 PM

Morley used laminated soundboards in their clavichords - very much to the detriment of the volume (which is practically non-existent anyway). I assume it was to ensure against splitting.







Posted By: Olek

Re: Laminated soundboards - 09/26/15 04:46 PM

Originally Posted by Del
Originally Posted by Olek
Del, are not laminated panels heavier?

Just like a solid panel that depends on the materials used and its construction. A 7.5 mm laminated spruce panel will weigh the same as a 7.5 mm solid panel. (Assuming variations for the character of individual pieces of wood.)


Quote
I find they deliver a lit of power, at the expense of tone variability.

I find that some pianos with solid panels "deliver a [lot] of power, at the expense of tone variability." In other words, just like solid panels have to be designed and constructed for a desired sound, so do laminated panels. Not all solid panels are the same. Neither are all laminated panels.


Quote
I wonder how much build in stress can be obtained, as I see no other way to fight the inertia of laminated panels.

Why fight inertia? Leave out what you don't want. Inertia in a soundboard system is the aggregate of all of its various parts and components. That includes the bridges, the panel, the screws, the bridge pins, the ribs, the finish material, etc.


Quote
The technology certainly did evolve, allowing nicer results.

That seem to be the top of the spectrum thar is damped, but now, this can be compensated by the use of a wire that produce more partials, I suppose (thinking of Pitthan wire here)

Again, the spectrum produced by a piano with either soundboard system is a function of its overall design and construction. Not just one thing like the construction of the soundboard panel.

Blanket statements like, "...the top of the spectrum that is damped," are no longer relevant.

ddf


Thank you,

Can you give links to some samples of pianos with laminated panels ?

I know the B series from Yamaha, for instance.

It is always a little frustrating to me as you are always so vague with statements as "good design", without much popularization on the basis of your thinking.

There is a residual stress obtained with the string pressure, and the balance of the panel against that pressure is certainly playing a role in the first moments of tone.

The high frequencies are better transmitted when the panel is "lightened" with the inner stress (energy reserve installation) obtained when forcing the panel into a cylindrical or elliptic shape.

I suppose that with the best orientation of the core, the sound speed in the panel is not slowed too much, but it seem that the speed of the tone is a major element, hence the "lightening" of the treble side as obtained with Steinway soundboards (by installing much stress with all glue joints)

I hear you when you say that laminated are more suitable for small pianos, if cracks are not really the problem, probably less stress can be installed (the stress within the panel being a protection against cracks, some "give" is allowed)

SO the thinking is certainly very different. But you are not giving much pointers there.

Regards



Posted By: Olek

Re: Laminated soundboards - 09/26/15 04:52 PM

For instance, that small vertical have significanly more power than any model of that size with a concrete soundboard.

[video:youtube]WvgmKcxRxHo[/video]

The tone is well defined, but dynamics is reduced may be because there is much power immediately (at light level of playing)

My gut feeling is that low inertia is what allow tone transparency.

Posted By: Dave B

Re: Laminated soundboards - 09/27/15 02:04 AM

Del, Thanks for the article. You've addressed many of the issues I've been wondering about. The one big question still remaining is life expectancy? Traditional spruce boards are, in my opinion, shot by the time they are 50 yrs old. Has anyone been able to do any testing of the effects caused by the woods natural deterioration?

Posted By: Del

Re: Laminated soundboards - 09/27/15 02:42 AM

Originally Posted by Olek
Can you give links to some samples of pianos with laminated panels ?

I know the B series from Yamaha, for instance.

It is always a little frustrating to me as you are always so vague with statements as "good design", without much popularization on the basis of your thinking.

Have you actually read the article I wrote? In that article I describe two rather different soundboard panel, one from Samick and one from Hailun. I went about as far as I could go without divulging what these companies would consider trade secrets. These soundboards appear in many different models built by these two companies.

Laminated soundboard panels also appear in some of the new models coming from YC/Weber but these will mostly be seen in China.

One of the problems with laminated soundboards in current production is that they are still used mostly in low-cost pianos. Typically these pianos have construction limitations quite separate from the design of their soundboards. I expect this to change as our attitudes about marketing them changes.



Quote
There is a residual stress obtained with the string pressure, and the balance of the panel against that pressure is certainly playing a role in the first moments of tone.

The high frequencies are better transmitted when the panel is "lightened" with the inner stress (energy reserve installation) obtained when forcing the panel into a cylindrical or elliptic shape.

I suppose that with the best orientation of the core, the sound speed in the panel is not slowed too much, but it seem that the speed of the tone is a major element, hence the "lightening" of the treble side as obtained with Steinway soundboards (by installing much stress with all glue joints)

Please forgive me, but I do not understand what all of this means. What is “a residual stress…?” I am guessing that you are talking about string downforce against the bridges and the soundboard’s pressing up against that force. If we want soundboard crown with a laminated soundboard panel it has to come from crowned ribs.

The rate at which an energy wave is carried through a panel such as a piano soundboard is a function of its stiffness as well as its mass. I don’t know what you mean when you say, “the high frequencies are better transmitted when the panel is ‘lightened’ with the inner stress (energy reserve installation) obtained when forcing the panel into a cylindrical or elliptical shape.”



Quote
I hear you when you say that laminated are more suitable for small pianos, if cracks are not really the problem, probably less stress can be installed (the stress within the panel being a protection against cracks, some "give" is allowed).

Laminated soundboard panels resist cracking because they are laminated. That is, there is a core and there are face veneers at some angle to that core. These panels inherently resist cracking.



Quote
So the thinking is certainly very different. But you are not giving much pointers there.

What kind of pointers are you looking for? I’m not going to publish specific details on designing and building a piano using a laminated soundboard panel. That is what I get paid to do. On the various forums that I participate in I try to answer questions of a general nature.

ddf
Posted By: Olek

Re: Laminated soundboards - 09/27/15 01:05 PM

Thanks Del, you answered to me by stating that the ribs are crowned, so there is no "slippage of the panel on the ribs during the gluing.

The stiffness is mostly due to the ribs ?

Not any stress installed between the layers ? That is the kind of thing I was curious about? The use of different layers allow to do that I suppose, by playing with dryness, but I have my doubts it is actually done that way.


Best regards


Posted By: phantomFive

Re: Laminated soundboards - 09/27/15 08:05 PM

I wish the article had spent more time talking about the quality of the sound from the laminated soundboard.

It's cool that it lasts longer, and holds a tune better. Those are good things. But ultimately I am not going to sacrifice sound quality for those aspects.

You did talk about it a little, I just wish you had focused more on that, because it is the primary concern.
Posted By: pianoloverus

Re: Laminated soundboards - 09/27/15 09:06 PM

Originally Posted by Del
Laminated soundboard panels resist cracking because they are laminated. That is, there is a core and there are face veneers at some angle to that core. These panels inherently resist cracking.
A more basic and probably simpler question: Do laminated soundboards resist cracking because because of the laminations or because the veneers are at some angle to the core or a combination of both factors?

Edit:Now that I've read your article I think that having an angle between the veneers and the core is the crucial element. Am I correct?

Regarding the article as a whole, I am continually impressed by your ability to explain things so clearly that a layman can understand and with a very fair(advantages and disadvantages)approach.
Posted By: Rickster

Re: Laminated soundboards - 09/27/15 09:29 PM

Originally Posted by phantomFive
I wish the article had spent more time talking about the quality of the sound from the laminated soundboard.

It's cool that it lasts longer, and holds a tune better. Those are good things. But ultimately I am not going to sacrifice sound quality for those aspects.

You did talk about it a little, I just wish you had focused more on that, because it is the primary concern.

I can't speak for Del, but the 5'8" Kimball Viennese baby grand I had, with the laminated sound board, had a pretty decent tone, in my view. I really liked that piano and enjoyed every minute I played it.

The only reason I sold it was because I found a Baldwin R I wanted. smile You know you have too many pianos when one has to go in order to get another one. grin

Here is a YT flick of the Kimball if interested. 5'8" Kimball Viennese with laminated soundboard

Rick
Posted By: S. Phillips

Re: Laminated soundboards - 09/27/15 11:07 PM

Congratulations to Del on a great article. Thanks so much for putting that all together. Great reading for customers and technicians alike.

Posted By: bleak

Re: Laminated soundboards - 09/28/15 01:28 AM

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?
Posted By: terminaldegree

Re: Laminated soundboards - 09/28/15 02:29 AM

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

Re: Laminated soundboards - 09/28/15 02:48 AM

Originally Posted by bleak
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?


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.

Posted By: bleak

Re: Laminated soundboards - 09/28/15 03:06 AM

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?
Posted By: BDB

Re: Laminated soundboards - 09/28/15 03:13 AM

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.)
Posted By: bleak

Re: Laminated soundboards - 09/28/15 04:10 AM

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?
Posted By: Steve Cohen

Re: Laminated soundboards - 09/28/15 12:50 PM

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

Re: Laminated soundboards - 09/28/15 12:51 PM

Originally Posted by bleak
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?


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.
Posted By: Rich Galassini

Re: Laminated soundboards - 09/28/15 12:58 PM

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.

Posted By: pianoloverus

Re: Laminated soundboards - 09/28/15 01:18 PM

Originally Posted by Rich Galassini
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
Posted By: JohnSprung

Re: Laminated soundboards - 09/28/15 05:34 PM

Originally Posted by Del
Originally Posted by Ed A. Hall
Del,

Do you envision laminated soundboards someday being made available for piano rebuilders to install in pianos needing rebuilding? There are so many older pianos with defective soundboards that so often don't get replaced for various reasons. I would think that there would be a market for these soundboards if made available to the piano rebuilding community.

I would think so as well. I don't see it happening any time soon, however.

ddf


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.

Posted By: Del

Re: Laminated soundboards - 09/28/15 06:06 PM

Originally Posted by Olek
Thanks Del, you answered to me by stating that the ribs are crowned, so there is no "slippage of the panel on the ribs during the gluing.

The stiffness is mostly due to the ribs ?

Not any stress installed between the layers ? That is the kind of thing I was curious about? The use of different layers allow to do that I suppose, by playing with dryness, but I have my doubts it is actually done that way.

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
Posted By: Del

Re: Laminated soundboards - 09/28/15 06:15 PM

Originally Posted by JohnSprung
Originally Posted by Del
Originally Posted by Ed A. Hall
Del,

Do you envision laminated soundboards someday being made available for piano rebuilders to install in pianos needing rebuilding? There are so many older pianos with defective soundboards that so often don't get replaced for various reasons. I would think that there would be a market for these soundboards if made available to the piano rebuilding community.

I would think so as well. I don't see it happening any time soon, however.

ddf


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.

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
Posted By: BDB

Re: Laminated soundboards - 09/28/15 07:03 PM

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

Re: Laminated soundboards - 09/28/15 07:16 PM

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.

Posted By: Del

Re: Laminated soundboards - 09/28/15 08:26 PM

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

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

ddf
Posted By: Steve Jackson

Re: Laminated soundboards - 09/29/15 09:38 AM

Originally Posted by chopin_r_us
Morley used laminated soundboards in their clavichords - very much to the detriment of the volume (which is practically non-existent anyway). I assume it was to ensure against splitting.


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.
Posted By: JohnSprung

Re: Laminated soundboards - 09/29/15 05:11 PM

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

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

ddf


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.


Posted By: Del

Re: Laminated soundboards - 09/29/15 06:05 PM

Originally Posted by JohnSprung
Originally Posted by Del
Originally Posted by BDB
Slicing veneers takes a lot of heat and moisture. Could that be adverse for the tonal qualities of the wood?

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

ddf


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
Posted By: Olek

Re: Laminated soundboards - 09/29/15 06:30 PM

there are peeled, sliced and sawed veneers

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

Posted By: Del

Re: Laminated soundboards - 09/29/15 08:16 PM

Originally Posted by Olek
there are peeled, sliced and sawed veneers

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

Rare and very expensive. Sawing veneers (along with the necessary post-processing) to a uniform 1 mm (or less) in thickness is very difficult. Especially with softwoods.

ddf
Posted By: Norbert

Re: Laminated soundboards - 09/29/15 09:17 PM

Lothar Thomma and others have long proven that laminated boards can have same or similar sound qualities - IF properly engineered.

The industry has been slow to adopt this simply because of marketing reasons.

I happen to be one who has expressed my opinion to same effect before.

"Laminated" for the most part, remains a dirty word almost like "clean diesel".. wink

The more clever ones among the manufacturers have long called their soundboards simply "all spruce"

Meaning: "all three sheets are made off spruce"...ha ha
[no names mentioned to protect the innocent...]

Norbert
Posted By: gynnis

Re: Laminated soundboards - 09/30/15 12:11 AM

Del, glad your getting some information out there. I think consistency is a big plus in laminated boards, especially for large production pianos. As spruce is becoming less available, the ability to use off-color pieces in the interior is a plus too.

Have you tried any other woods besides the traditional spruce? What is the impact of the adhesive and pressure during lamination?
Posted By: Del

Re: Laminated soundboards - 09/30/15 04:47 AM

Originally Posted by gynnis
Have you tried any other woods besides the traditional spruce? What is the impact of the adhesive and pressure during lamination?

I have not tried other wood species but others have. Baldwin, for a time, used poplar and bass.

The legendary StoryTone soundboard was made of what they called "mahogany." It was actually lauan -- a wood that was euphemistically called Philippian mahogany at the time.

Any number of woods could be used as long as attention was paid to their stiffness and mass characteristics.

The biggest single layup problem that I'm aware of is an inadequate amount of adhesive. Over the years some panel manufacturers have attempted to skimp on the adhesive and this can lead to delamination later on. Other problems are out-of-date adhesive, incorrect heat (either too high or too low), improperly dried veneers or core stock, etc. In other words, the same rules that apply for good wood processing still apply.

ddf
Posted By: phacke

Re: Laminated soundboards - 09/30/15 06:19 AM

Originally Posted by gynnis
As spruce is becoming less available, the ability to use off-color pieces in the interior is a plus.


Greetings, I think this subset of what you wrote is the key point.

The other advantages being stated are not so clear in my opinion.

I don't know if the thinking has advanced, but in some previous thread, I pointed out that for a given moisture absorption, laminates are actually under more stress because the laminates are constrained by the axial grain components of the wood layers they are adhered to, such that wood-cellular compression damage would occur through plastic deformation or fatigue rather than out of plane bending (piano going out of tune). The response, I recall, was that there are moisture barrier films. But, moisture barriers films should be possible to apply on conventional boards too, giving them that equal advantage if it so desired.

I would say another disadvantage of laminate boards is that they are more complicated, which means more things can go wrong. Secondly, unlike conventional boards, one cannot inspect the details of construction as easily to see if those moisture barrier films will be successful, correct processing of the new adhesives, uniformity of wood used in the core such that anticipated piano-to-piano reproducibility will be realized, and so forth.

That said, there is no reason to think laminate sound boards cannot sound good.. I wish them all the success.

Best wishes-
Posted By: Olek

Re: Laminated soundboards - 09/30/15 07:41 AM

Originally Posted by Del
Originally Posted by Olek
there are peeled, sliced and sawed veneers

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

Rare and very expensive. Sawing veneers (along with the necessary post-processing) to a uniform 1 mm (or less) in thickness is very difficult. Especially with softwoods.

ddf


There areonly two places that make those sawed veener, here is a video showing the 2 saw and the woods

The saw was an ivory saw, modified, enlarged . Most parts are in wood to absorb vibrations.
They say the spend a lot of time on sharpening the blades

They can saw up to 1 meter large.

I think the veneers are thicker than 1 mm most often, 12 or 13/10 mm.

http://www.wat.tv/video/bois-montant-version-finale-fb92_2frvr_.html
Posted By: Del

Re: Laminated soundboards - 09/30/15 08:05 AM

Originally Posted by phacke
... I don't know if the thinking has advanced, but in some previous thread, I pointed out that for a given moisture absorption, laminates are actually under more stress because the laminates are constrained by the axial grain components of the wood layers they are adhered to, such that wood-cellular compression damage would occur through plastic deformation or fatigue rather than out of plane bending (piano going out of tune). The response, I recall, was that there are moisture barrier films. But, moisture barriers films should be possible to apply on conventional boards too, giving them that equal advantage if it so desired.

Have you actually read the article? Some of your concerns are addressed with the discussion about the face-to-core grain orientation being used in modern laminated soundboard panels.

All soundboards are compromises of one sort or another. It is true that the face and core veneers are affected by changes in moisture content. They are, after all, still made of wood. The perpendicular-to-grain compression and tensile stresses are primarily confined to the core by virtue of its thickness. Because they are very thin the face veneers are not subject to appreciable stress failure. The cellular structure of the wood is affected by changes in moisture content but experience has shown that the structural integrity of both the core and the face veneers is not adversely affected. At least not within the temperature and humidity swings normally encountered in the average home. Rather, laminated soundboard panels have proven to be both more stable and more durable through climate extremes than their solid spruce counterparts.

Many piano makers specify a somewhat higher ambient moisture content (compared to solid spruce construction) when their panels are glued up so they start out much closer to the average moisture content found in typical homes than is common with solid wood panels. This reduces the compression peaks without introducing excessive tensile stresses. Several decades of experience with high quality and high performance laminated soundboard panels have shown that your concerns are really non issues. I don’t know of any company that, after switching from solid soundboard panels to laminated soundboard panels, has found its warrantee costs going up. Quite the opposite, they go down.

(By the way, it is a common misconception that modern laminated soundboard panels do not go through any dimensional changes with fluctuations in moisture content. Only a pure “plywood” panel—i.e., a panel with the face veneers at 90° to the core—approaches absolute stability. While this construction was common years ago, modern laminated soundboard panels—as noted in the article—are typically laid up with crossing angles somewhere between 45° and 15°. A three-ply panel with the faces laid up at 0° to the core would act quite like a “solid spruce” soundboard panel. As the crossing angles increase the panel acts less like a solid spruce panel and more like a plywood panel. Everything is a compromise. A panel laid up at 45° will be dimensionally more stable than one laid up at 15° but a panel laid up at 15° will perform more like a solid spruce panel.)


Quote
I would say another disadvantage of laminate boards is that they are more complicated, which means more things can go wrong. Secondly, unlike conventional boards, one cannot inspect the details of construction as easily to see if those moisture barrier films will be successful, correct processing of the new adhesives, uniformity of wood used in the core such that anticipated piano-to-piano reproducibility will be realized, and so forth.

You are right in theory but this has not proven to be an issue in practice. Piano manufacturers routinely tear laminated soundboard panels apart to verify that their suppliers are giving them panels that meet their specifications. There are now tens, if not hundreds of thousands of pianos in service with laminated soundboards. If there were endemic problems with this construction I would have expected them to have surfaced by now. Indeed, performance consistency and structural integrity are among the advantages of this construction.

ddf
Posted By: ando

Re: Laminated soundboards - 09/30/15 11:13 AM

Originally Posted by Olek


There areonly two places that make those sawed veener, here is a video showing the 2 saw and the woods


http://www.wat.tv/video/bois-montant-version-finale-fb92_2frvr_.html


That video is hard going if you don't understand French...
Posted By: Del

Re: Laminated soundboards - 09/30/15 05:30 PM

Originally Posted by Olek
Originally Posted by Del
Originally Posted by Olek
there are peeled, sliced and sawed veneers

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

Rare and very expensive. Sawing veneers (along with the necessary post-processing) to a uniform 1 mm (or less) in thickness is very difficult. Especially with softwoods.

ddf


There areonly two places that make those sawed veener, here is a video showing the 2 saw and the woods

The saw was an ivory saw, modified, enlarged . Most parts are in wood to absorb vibrations.
They say the spend a lot of time on sharpening the blades

They can saw up to 1 meter large.

I think the veneers are thicker than 1 mm most often, 12 or 13/10 mm.

http://www.wat.tv/video/bois-montant-version-finale-fb92_2frvr_.html

There are several companies making powered frame saws. One of them can be seen here:
http://www.ogden-group.com.php53-2....oads/documents/Eco-Power/EcoPowerWeb.pdf

This particular machine—Ogden—specifies a minimum veneer thickness of 2.0 mm. I've talked to owners who claim to have made their own blade spacers and who have been able to go some thinner than this.

All veneer saws share some common problems: First, they are very slow. Even sawing multiple veneers in a single pass—as with the Ogden—the saws cut slowly so the time investment is considerable. This raises the cost for something like production laminated soundboards to a prohibitive level.

Second, they are inefficient (in their use of raw material) and just about as much wood ends up as sawdust. This rather defeats the goal of preserving spruce forests.

Third, even with careful "tweaking" it is difficult to saw veneers thin enough for soundboard face veneers. As well, sawn veneers, by their nature, have rough surfaces—all of these machines are, after all, simply powered frame saws—and have to be sanded prior to gluing and this wastes more wood and takes more time.

ddf
Posted By: Olek

Re: Laminated soundboards - 09/30/15 05:40 PM

The difference is in the colors and the deepness of the shades , the figures of the wood, that is why they are used for furniture, marquetry, decoration.

In the video he shows at some point the difference between sawed veener and cut veener, by spraying some alcohol on it.

The figures in the wood are more contrasted and more colored with the sawed one (at the back)

When I think that on our old pianos there is plenty of them, on Pleyel even gluing together 2 pieces of standard cut veneer does not make the original thickness.


I think they are best finished with the classical "French polishing" process, with shellac and alcohol .
Then the fine sanding is done at the same time the pore is closed , at the beginning of the job, using pumice and alcohol to polish the surface and create the sealer, that process is keeping the deepness as the fibers are not crushed.



Posted By: Del

Re: Laminated soundboards - 09/30/15 06:03 PM

Originally Posted by Olek
The difference is in the colors and the deepness of the shades , the figures of the wood, that is why they are used for furniture, marquetry, decoration.

...

The figures in the wood are more contrasted and more colored with the sawed one (at the back)

Yes, sawn veneers have many wonderful characteristics. They are still completely impractical for production piano manufacturing.

ddf
Posted By: JohnSprung

Re: Laminated soundboards - 09/30/15 09:54 PM

Originally Posted by Del
The legendary StoryTone soundboard was made of what they called "mahogany." It was actually lauan -- a wood that was euphemistically called Philippian mahogany at the time.


There's a Story & Clarke console circa 1970 (#457855) that I play at a private club the first Wednesday of every other month. It seems to me to be a fairly ordinary old beater piano.

Posted By: JohnSprung

Re: Laminated soundboards - 09/30/15 09:58 PM

Originally Posted by Del
It is true that the face and core veneers are affected by changes in moisture content. They are, after all, still made of wood.


So then the adhesives don't significantly impede the movement of moisture into and out of the core, right? Might it be possible to find adhesives that do block water? If so, would that be a good idea or a bad one?

Posted By: David-G

Re: Laminated soundboards - 09/30/15 11:39 PM

Originally Posted by Rich Galassini
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.

Sorry, this might sound a naïve question, but how exactly would you define downbearing? Is it the same as crown?
Posted By: Rickster

Re: Laminated soundboards - 09/30/15 11:53 PM

Originally Posted by David G
Sorry, this might sound a naïve question, but how exactly would you define downbearing? Is it the same as crown?

Hi David,

I don't know much about piano technology, but I think downbearing and crown are related...

You can check the downbearing with a downbearing gauge; you place the gauge on the center of the string on the bridge, and measure the gap/distance between the gauge and string near the bridge.

Downbearing is the force of the string tension pushing down on the bridge, which transfers the sound from the string through the bridge and into the soundboard.

You use a string to measure the crown by stretching the string tight from one side of the soundboard to the other on the bottom side, and measure the gap between the string and soundboard in the center of the soundboard.

If the soundboard has little or no crown, it may well have little or no downbearing, which could affect the transfer of energy from the string to the soundboard, affecting tone.

Of course, I could be wrong. grin

Rick
Posted By: acortot

Re: Laminated soundboards - 10/01/15 12:05 AM

just a little correction to make regarding the Pleyel laminated soundboards made in the early 1800's

They were veneered with whatever veneer was used on the case of the piano, which could have been Brazilian Rosewood, 'Cuban' Mahogany or other varieties used in those days for furniture.

The selling point was that they were 'guaranteed not to crack'

the soundboards that were veneered also tended to be a bit thinner to their normal counterparts, probably because of the increased resistance to splitting and had a cleaner sound, in my experience.



Posted By: acortot

Re: Laminated soundboards - 10/01/15 12:12 AM

one thing that Laminated Soundboards could do to improve the lightness to stiffness ratio could be to substitute the middle section with a lighter and more porous wood.

I had a set of 3-ply drums which had the middle layer made of a softwood with hardwood veneer.. sounded good

I mean, if you use hardwood on the outside and then a very light wood in the centre, you would get the stiffness but lightness as well..

might sound awful but maybe it wouldn't.. say in the bass section
Posted By: Del

Re: Laminated soundboards - 10/01/15 02:44 AM

Originally Posted by JohnSprung
Originally Posted by Del
It is true that the face and core veneers are affected by changes in moisture content. They are, after all, still made of wood.


So then the adhesives don't significantly impede the movement of moisture into and out of the core, right? Might it be possible to find adhesives that do block water? If so, would that be a good idea or a bad one?


No. The common adhesives used for this purpose are not vapor resistant. The only adhesive I'm aware of that could form an effective vapor barrier is epoxy. Using epoxy would slow the process and drive up the cost considerably. I'm not sure just what, if any, benefit would be derived with this. I can think of some potential theoretical advantages but I rather suspect they would be just than -- theoretical.

ddf
Posted By: Del

Re: Laminated soundboards - 10/01/15 03:02 AM

Originally Posted by phantomFive
I wish the article had spent more time talking about the quality of the sound from the laminated soundboard.

It's cool that it lasts longer, and holds a tune better. Those are good things. But ultimately I am not going to sacrifice sound quality for those aspects.

You did talk about it a little, I just wish you had focused more on that, because it is the primary concern.

No, I did not say much about sound quality in this article. It was really outside the scope of the article. What I wanted to address was the unwarranted confusion and fears that surround pianos using laminated soundboard panels.

Performance—timbre or tone quality, action performance, etc.—are things the consumer can readily evaluate for himself or herself. The piano either sounds good to their ear or it does not. If the piano does not sound good then how it is constructed is really moot; the buyer should move on. If it does sound good then I want the reader to understand that laminated soundboard construction is a positive feature and not something to be afraid of. It is up to the buyer to define "good."

ddf
Posted By: Del

Re: Laminated soundboards - 10/01/15 03:04 AM

Originally Posted by acortot
just a little correction to make regarding the Pleyel laminated soundboards made in the early 1800's

They were veneered with whatever veneer was used on the case of the piano, which could have been Brazilian Rosewood, 'Cuban' Mahogany or other varieties used in those days for furniture.

The selling point was that they were 'guaranteed not to crack'

the soundboards that were veneered also tended to be a bit thinner to their normal counterparts, probably because of the increased resistance to splitting and had a cleaner sound, in my experience.

Thank you for the correction. Now, if I just remember it....

ddf
Posted By: Del

Re: Laminated soundboards - 10/01/15 03:11 AM

Originally Posted by acortot
one thing that Laminated Soundboards could do to improve the lightness to stiffness ratio could be to substitute the middle section with a lighter and more porous wood.

I had a set of 3-ply drums which had the middle layer made of a softwood with hardwood veneer.. sounded good.

I mean, if you use hardwood on the outside and then a very light wood in the centre, you would get the stiffness but lightness as well.

might sound awful but maybe it wouldn't.. say in the bass section.

There are many possible variations that could be used. But we are back to the marketing challenges. Many piano salespeople already misrepresent the qualities of all-spruce laminated soundboard panels. It frightens me to consider what would be said about a laminated soundboard panel using padauk faces on a balsa core.

I don’t want to fight that battle until we’ve made some progress on this one.

ddf
Posted By: Del

Re: Laminated soundboards - 10/01/15 03:16 AM

Originally Posted by Dave B
Del, Thanks for the article. You've addressed many of the issues I've been wondering about. The one big question still remaining is life expectancy? Traditional spruce boards are, in my opinion, shot by the time they are 50 yrs old. Has anyone been able to do any testing of the effects caused by the woods natural deterioration?

Who knows? Laminated soundboard panels are not subjected to the same damaging stresses common to solid panels. Given that I would expect an indefinite lifespan. That is, the piano may well wear out are expire for other reasons but the soundboard itself should be fairly stable.

ddf
Posted By: phacke

Re: Laminated soundboards - 10/01/15 05:31 AM

Thanks very much Mr. Fandrich for your explanations above -

I went back to previous thread and it looks like I confounded who had what positions with respect to moisture barrier properties of adhesives. You clarified your understanding above as well.

On the other hand, I understand the reasoning behind the effects of grain angles, or at least I think I do. Modulus of elasticity and yield strength of wood is relatively much higher in the axial(longitudinal) direction, such that the thinner surface veneer at an angle to the thicker core can sufficiently constrain expansion of the core in the all-sensitive radial and tangential directions with increased humidity, the extent which will vary with that angle.

You wrote:

Originally Posted by Del
"Many piano makers specify a somewhat higher ambient moisture content (compared to solid spruce construction) when their panels are glued up so they start out much closer to the average moisture content found in typical homes than is common with solid wood panels. This reduces the compression peaks without introducing excessive tensile stresses."


Sorry, I don't understand the key point here. Of course a compression crown board comes out of the board-making process, well, compressed and that much closer to incurring compression peaks,
And that's why some favor rib crowning, of course. but…

There would be no question that laminates display less macro cracks then boards. That's what glued laminates do, plywood, etc. I can understand why the piano market channels would prefer that, reduced warranty costs, etc.

[edit:I can also understand that thinner layers of pretty much anything are less likely to have a macro crack nucleate for a given stress, such as is the case for the thinner veneer surfaces, maybe not applicable to the core though.]

If it is claimed it has better tuning stability, then the board core is being constrained . Said simply though, my general understanding of things makes me say, a more constrained system will experience more stress, and higher stress generally speaking, leads to more damage, somewhere. My thinking would be that since macro cracks are prevented from opening by the laminate, it might instead be on the micro scale.

If I were reading my above paragraph objectively, I might say, that guy is setting up the perfect conspiracy theory explaining that the bad stuff happens where you can't see it. But again, generally, a more constrained system should experience relatively more stress with the humidity changes, I think. So that might need a simple explanation showing that isn't the case here.

Originally Posted by Del
Piano manufacturers routinely tear laminated soundboard panels apart to verify that their suppliers are giving them panels that meet their specifications.


So they are outsourcing their boards? Interesting.

Thanks again-
Posted By: Steve Cohen

Re: Laminated soundboards - 10/01/15 02:08 PM

Originally Posted by Del
But we are back to the marketing challenges. Many piano salespeople already misrepresent the qualities of all-spruce laminated soundboard panels. It frightens me to consider what would be said about a laminated soundboard panel using padauk faces on a balsa core.

I don’t want to fight that battle until we’ve made some progress on this one.


The marketing issues surrounding laminated soundboards are very challenging and we here on PW can help.

Consider a novice shopper in a town with two dealerships. Dealer A carries the Kaiserway line with a high-tech laminated soundboard which the dealer extols through the virtues that Del has pointed out. The piano sounds good to the shopper, but being uneducated in piano tone, they aren't "attached" to performance.

They go to Dealer B who carries the competitively priced Henway, entry-level piano with a low-grade solid spruce soundboard. They point out that out the of the top 25 brands of pianos on the market none use a laminated board. And, every single one of these "top 25" uses a solid spruce board, "just like our Henway". It is a compelling argument.

As pianos with these high-tech boards hit the market and novices inquire about them here on PW, we need to help make the case for considering them.

Posted By: Norbert

Re: Laminated soundboards - 10/01/15 06:34 PM

Steve's among post underlines an ongoing dilemna in the industry.

That's why IMHO salespeople carry an additional burden to explain things right.
Something that is not always happening.

Quote
The piano sounds good to the shopper, but being uneducated in piano tone, they aren't "attached" to performance.


Another point why education of the 'honest type' is so very important.Wondering how many times the 'Volkswagen story' would repeat itself if things would come out later...

At same time it's become fact that even as player it is becoming increasingly difficult to tell exactly which is which.

Which, IMHO is good for consumers.

Today there are many great sounding pianos on the market using laminate i.e. "all spruce" soundboards. A term often used to not tell the whole story or even deceive.

Ritmuller, as many other makes, has laminates among it's lower rated series, something we carefully point out to every single customer. The nice thing not everybody is noticing or caring about this. As Del pointed out, there are also some advantages.

Of course "all spruce" pianos are always cheaper - another good thing. So why not earn one's business being forthright and open about things?

Wishing that everybody else would be doing same.

Listening in and careful exploring a piano's sound potential is still where it's all at. IMHO

It's similar like good food: one's it tastes great one needs spending little time to explore exactly "why".

Nor would one have the need to move on to another restaurant in the hope of "getting still better".

Norbert wink
Posted By: Del

Re: Laminated soundboards - 10/01/15 06:49 PM

Originally Posted by phacke
… On the other hand, I understand the reasoning behind the effects of grain angles, or at least I think I do. Modulus of elasticity and yield strength of wood is relatively much higher in the axial (longitudinal) direction, such that the thinner surface veneer at an angle to the thicker core can sufficiently constrain expansion of the core in the all-sensitive radial and tangential directions with increased humidity, the extent which will vary with that angle.

You wrote:

Originally Posted by Del
"Many piano makers specify a somewhat higher ambient moisture content (compared to solid spruce construction) when their panels are glued up so they start out much closer to the average moisture content found in typical homes than is common with solid wood panels. This reduces the compression peaks without introducing excessive tensile stresses."


Sorry, I don't understand the key point here. Of course a compression crown board comes out of the board-making process, well, compressed and that much closer to incurring compression peaks,
And that's why some favor rib crowning, of course. but…

There would be no question that laminates display less macro cracks then boards. That's what glued laminates do, plywood, etc. I can understand why the piano market channels would prefer that, reduced warranty costs, etc.

[edit:I can also understand that thinner layers of pretty much anything are less likely to have a macro crack nucleate for a given stress, such as is the case for the thinner veneer surfaces, maybe not applicable to the core though.]

If it is claimed it has better tuning stability, then the board core is being constrained. Said simply though, my general understanding of things makes me say, a more constrained system will experience more stress, and higher stress generally speaking, leads to more damage, somewhere. My thinking would be that since macro cracks are prevented from opening by the laminate, it might instead be on the micro scale.

If I were reading my above paragraph objectively, I might say, that guy is setting up the perfect conspiracy theory explaining that the bad stuff happens where you can't see it. But again, generally, a more constrained system should experience relatively more stress with the humidity changes, I think. So that might need a simple explanation showing that isn't the case here.

I’m not quite sure I get either the point or the question but I'll take a shot at this and see what happens.

All soundboard panels are subject to stress. If you think about it, what is the conventional solid spruce panel/rib configuration but a constrained two-ply laminate. The solid spruce panel is still subject to perpendicular-to-grain compression and tension even though there is no cross ply surface veneer.

Wood is moderately compliant—spruce can handle up to about 1% perpendicular-to-grain compression and about 0.5% stretch without exhibiting physical damage. If you start with wood that is very dry—say, 4%—and constrain that piece of wood in the perpendicular-to-grain direction and move it to an atmosphere that raises the moisture content to 18% you’re going to exceed that limit. If you hold it there for any length of time you’re going to have a problem. If you start at 6.5% or 7% and raise it to the same 18% moisture content you will have considerably less perpendicular-to-grain compressive stress and you might get by with it. At least you’ll get by with it longer.

But I’m not sure if this really matters in laminated soundboard construction. Essentially what we have is a thin piece of lumber-core plywood. This is the stuff upright case parts and grand lids and other flat parts were made of for a hundred-plus years before MDF came along. Longer than that in other woodworking endeavors. Even while the solid spruce soundboards inside these pianos were self-destructing their lids were doing just fine. Were there macro- or micro-cracks developing in the (usually poplar) core material? I have no idea; I’ve never seen any signs of them but I’ve never examined any of this wood through a microscope either.

The core panel in a laminated soundboard panel is also constrained. Do macro- or micro-cracks develop in this wood? Again, I have no idea. They might but I’ve never seen any evidence of such. As with the above-mentioned lumber-core plywood, though, I’ve not examined any of them through a microscope. Some damage might well be there—if I get the chance someday I’ll look—but even if I do detect some such, my question then becomes: so what?

There are hundreds of thousands of pianos in service with laminated soundboard panels in them. Their track record for both stability and durability is excellent. There is an occasional—very occasional—report of one of these panels delaminating. This is usually, if not always, traced to an undetected poor glue spread during manufacture. I’ve never heard of a failure that could be traced to either macro- or micro-cracks in either the core or face veneers.

So, while your question is intellectually interesting I can see it having any particular relevance in the real piano world. That said, if I’ve missed your point we can try again.


Quote
Originally Posted by Del
Piano manufacturers routinely tear laminated soundboard panels apart to verify that their suppliers are giving them panels that meet their specifications.


So they are outsourcing their boards? Interesting.

Some do, others make them in-house. In either case a manufacture with a functioning quality control department will be testing critical components—including laminated soundboard panels—to verify that they conform to design and quality standards.

ddf
Posted By: JohnSprung

Re: Laminated soundboards - 10/01/15 08:11 PM

Originally Posted by Del
Using epoxy would slow the process and drive up the cost considerably. I'm not sure just what, if any, benefit would be derived with this. I can think of some potential theoretical advantages but I rather suspect they would be just than -- theoretical.


It might be worth trying some prototypes. If there is an advantage, then work on increasing the efficiency/reducing the cost. Perhaps there's something to be learned from the fiberglass boat builders....

Posted By: Norbert

Re: Laminated soundboards - 10/01/15 08:22 PM

The long and short of this is that laminates are cheaper to make, offering the public some viable, very acceptable alternatives to solids.
People should perhaps check the specs of their own pianos [if made available by company..] - many would perhaps be amazed....
If willing to pay more, most of the discussion is mute.
Good laminates, i.e. "all spruce" soundboards can and often 'are' a great alternative.
But it would be nice if the industry [including store salesmen..] would be totally honest about this issue.
It's was one of the reasons why we dropped an entire line before. They started out right but then changed midstream.
Nothing to hide, really....

Norbert smile
Posted By: phacke

Re: Laminated soundboards - 10/02/15 05:36 AM

Greetings again, Mr. Fandrich
Thanks so much for taking the time to explain so that I can understand your thinking about the matter.

Quote
I’m not quite sure I get either the point or the question but I'll take a shot at this and see what happens.


My read is you have the jist of of, but, specifically, I was asking for comment on this issue I wrote of:
Quote
If it is claimed it has better tuning stability, then the board core is being constrained..., a more constrained system will experience more stress, and higher stress generally speaking, leads to more damage, somewhere.


So the literal questions are: Is this true or not? If not, why is this system special or what am I missing?

In more dramatic terms, if we are moving from freezing ice in a rubber container to a ceramic container (the more constrained system), the stresses will be actually higher and something may give, the ice will fissure or the ceramic container will fracture so that stress is relieved.

The mechanism is clear that on axis grains of the laminate are constraining the core, and to the extent one says that tuning stability is improved, I am saying that stresses in that system will be actually higher than in the conventional board, and if a conventional board yields or fatigues, then the laminate system will too, and if the stresses are higher, then moreso.

You of course have many observations you wrote of, and probably more that you have not discussed, but I can address my concerns with respect to what your wrote of here.

Quote
All soundboard panels are subject to stress. If you think about it, what is the conventional solid spruce panel/rib configuration but a constrained two-ply laminate. The solid spruce panel is still subject to perpendicular-to-grain compression and tension even though there is no cross ply surface veneer.


In a round about way, this example can be an illustration supportive of my point. In humid conditions, conventional boards fail at the rib/board interface in no small part, I think, because of the various mismatches at that interface. Of couse, what the adhesives are doing matters too in this mix. Specifically for humid conditions, Steinway screws the ribs on to deal with this, to an extent. Of course we need to be quantitative about this, and we do, below.

Quote
Wood is moderately compliant—spruce can handle up to about 1% perpendicular-to-grain compression and about 0.5% stretch without exhibiting physical damage. If you start with wood that is very dry—say, 4%—and constrain that piece of wood in the perpendicular-to-grain direction and move it to an atmosphere that raises the moisture content to 18% you’re going to exceed that limit. If you hold it there for any length of time you’re going to have a problem. If you start at 6.5% or 7% and raise it to the same 18% moisture content you will have considerably less perpendicular-to-grain compressive stress and you might get by with it. At least you’ll get by with it longer.


I have seen quite clear data on this too, for example, HERE

See p 471, the figure on bottom right.

The solid diagonal line indicates the stress free interface state for various starting relative humidity (RH), such as I suppose would be found at the center region of a rib crown board. If humidity goes up the board expands, constrained by the rib, it goes into compression. Depending on what your staring humidity was, you can see by the upper data points and line that yield happens with a 10% to 30% RH swing to the upside. That graph is showing yield for perfectly constrained tangential wood (and I assume the axial dimension of the of the rib is nearly a perfect constrainer in its longitudinal/length direction), but let's face it, even the highest quality boards are rarely perfectly quarter-sawn, and sorry, I have think it may be at times less perfectly so if it is laminated with a face veneer.

Now, if we are saying the laminated board moves less with humidity, it is more perfectly constrained, the stresses on the core are higher, so I'm saying this rational is telling me that the core in the laminated board is more likely to yield than the conventional board.

(Keep in mind too that materials, including wood, experience fatigue with cyclic stress at levels below their yield point)

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But I’m not sure if this really matters in laminated soundboard construction. Essentially what we have is a thin piece of lumber-core plywood. This is the stuff upright case parts and grand lids and other flat parts were made of for a hundred-plus years before MDF came along. Longer than that in other woodworking endeavors. Even while the solid spruce soundboards inside these pianos were self-destructing their lids were doing just fine. Were there macro- or micro-cracks developing in the (usually poplar) core material? I have no idea; I’ve never seen any signs of them but I’ve never examined any of this wood through a microscope either.


I need to go on a little tangent here first before addressing this. This is a bit of a complaint about the ink that is spent on the fact that laminated boards don't crack.

A key point: cracking is not their particular failure mechanism.

So if we are looking for macro cracking as a metric, we are looking in the wrong place.

Back to your paragraph above. It might be a bit of a tangent, because mahogany is the veneer of choice which has very special properties as a rainforest wood, a wood of choice for high humidity applications, and the substrate and mounting protocol is different too.

That said, I observe checking, not lacquer checking, but veneer checking on old pianos. Checking is the failure mechanism of the thin wood laminates due to humidity cycling. The laminate soundboard has thicker top and bottom surfaces with more all-around strength. So yet again, the system is different.

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The core panel in a laminated soundboard panel is also constrained. Do macro- or micro-cracks develop in this wood? Again, I have no idea. They might but I’ve never seen any evidence of such. As with the above-mentioned lumber-core plywood, though, I’ve not examined any of them through a microscope. Some damage might well be there—if I get the chance someday I’ll look—but even if I do detect some such, my question then becomes: so what?


I think we will all agree that it is the sound that matters over the time in the use environment. I have to think that collapsed wood cell structure is not a good thing, damps sound, etc, but I have not studied this matter.

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There are hundreds of thousands of pianos in service with laminated soundboard panels in them.


Wow, that's a lot. where does this data come from?

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So, while your question is intellectually interesting I can see it having any particular relevance in the real piano world. That said, if I’ve missed your point we can try again.


The thing is, if your read a book like "The Toyota Way" and read about double loop learning, you come away with the understanding that to have good quality results, one has to understand fundamentally what is going on. Yes, observables on old sound boards are good. experience as you have with changing the lamination angle is good. But to understand such things as, what are the tolerances? to understand the implications, before they happen, of controlled and uncontrolled changes in the process, the theoretical understanding is necessary too. When I see the conundrum, where the laminated board is potentially in a higher stress state, you know, I think it is a valid concern. I am not bringing up the effects of the phases of the moon here!

When we watched Japan come up, we thought they were doing nothing but copying without understanding.

Changes in attitude were driven in view of this, buy the US gov't no less.
In the time of pre mid-70’s: Only non-commercial true research was supported

then, mid-70’s: about-face to focus only on ‘applied’ science (misreading, and then 'thinking' they were emulating Japan)

USA across the board, started to make junk, with many quality problems.

Then, there was a drifting to realization in the late ‘80s that “you have to understand what it is you are doing”
The organizations that survive are the organizations that keep learning, fundamentally understanding. Actually, I think your are generally on to this, so all is good.

Spiel-off, thank you for listening, best regards,
Posted By: Del

Re: Laminated soundboards - 10/02/15 08:09 AM

Originally Posted by phacke
My read is you have the jist of of, but, specifically, I was asking for comment on this issue I wrote of:
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If it is claimed it has better tuning stability, then the board core is being constrained..., a more constrained system will experience more stress, and higher stress generally speaking, leads to more damage, somewhere.

Not necessarily. If a beam is capable of supporting, say, a 100 lb load and you put a 10 lb load on it the beam will be stressed but not damaged.


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So the literal questions are: Is this true or not? If not, why is this system special or what am I missing?

Well, a smoking gun would help. In other words it would help to find a few laminated soundboard panels that were exhibiting signs of stress failure. But, if such exist I’m not aware of them.

If the laminated soundboard panel is constructed with reasonable care it will be stressed at some times of the year but that does not necessarily mean it will be damaged. As noted earlier, spruce can withstand a certain amount of compression and tension without cellular failure. The core of laminated soundboard panels stay within this range. (Assuming the manufacturer has good and proper controls on moisture content.)

The acoustics of (some types of) solid spruce boards changes over time because the panel stiffness changes. True, this change takes place because of permanent compression—i.e., compression set—or damage to the wood cells but, by itself, it is not the cellular damage that causes the change in performance. It is the resulting loss of stiffness that that is the problem.

This does not happen with the laminated soundboard panel. At least not to any measurable degree. Soundboard systems using laminated panels—modern ones, at least—have some inherent amount of stiffness longitudinally to the aggregate grain angle. They will be somewhat less stiff perpendicular to the aggregate grain angle. (This is somewhat similar to the stiffness characteristics of a solid spruce panel before the ribs are glued on although its stiffness longitudinal-to-grain will be a little lower and its stiffness perpendicular-to-grain will be a little higher.) This panel is further stiffened by the attachment of (usually) crowned ribs underneath (or behind) the panel. It is an inherently stable system.


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The mechanism is clear that on axis grains of the laminate are constraining the core, and to the extent one says that tuning stability is improved, I am saying that stresses in that system will be actually higher than in the conventional board, and if a conventional board yields or fatigues, then the laminate system will too, and if the stresses are higher, then moreso.

Not necessarily. It would depend on the moisture content starting point.


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I need to go on a little tangent here first before addressing this. This is a bit of a complaint about the ink that is spent on the fact that laminated boards don't crack.

A key point: cracking is not their particular failure mechanism.

So if we are looking for macro cracking as a metric, we are looking in the wrong place.

Then what, pray tell, are we looking for? What, exactly, is their failure mechanism? Cracking longitudinal to the aggregate grain? I can’t see that happening. Cracking perpendicular to the aggregate grain? Here we’re into your macro- or micro-cracking but, again, my question is—so what? If such exists you’ll have to demonstrate—or explain—to me why it matters to the function of the soundboard panel.

Conceivably some cellular degradation could develop in the early wood of the core but, again I ask, so what? Exactly how is this going to affect the performance of the soundboard panel? What physical characteristic of the assembly is going to change? Are the ribs going to change? Conceivably the panel stiffness could change slightly but this would only be perpendicular to the aggregate grain angle of the panel.


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I think we will all agree that it is the sound that matters over the time in the use environment. I have to think that collapsed wood cell structure is not a good thing, damps sound, etc, but I have not studied this matter.

I’ve seen no studies that support this view. But, like you, I’ve not studied the matter.


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There are hundreds of thousands of pianos in service with laminated soundboard panels in them.


Wow, that's a lot. where does this data come from?

Consider that a company like Samick—one of the world’s larger piano makers—builds, perhaps, 10,000 pianos a year using laminated soundboard panels. (The actual count may be somewhat more or less but I doubt I’m far off. Over a ten year period that would be 100,000 from just one company. But Samick has been building pianos with laminated soundboard panels for several decades. Now factor in YC/Weber with similar figures. And Pearl River with considerably higher production numbers. And then add in the production numbers for all the other piano makers in Asia using laminated soundboard panels—Yamaha, Kawai, Parsons, Hailun, Pearl River, etc.—and then consider that most of these companies have also been making pianos with laminated soundboard panels for some decades. Several hundreds of thousands is a very low estimate.

In my article I focused on soundboards made by two companies—Samick and Hailun—both of which, while their designs differ, make soundboards of relatively high quality. It’s safe to say companies like Yamaha, Kawai, Parsons, Pearl River, etc. also make (or buy) laminated soundboard panels of relatively high quality. We would expect all of these to perform well over time. But there are other companies in China that make (or buy) laminated soundboard panels of rather dubious quality and even these have not developed reputations for structural failure.


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The thing is, if your read a book like "The Toyota Way" and read about double loop learning, you come away with the understanding that to have good quality results, one has to understand fundamentally what is going on. Yes, observables on old sound boards are good. experience as you have with changing the lamination angle is good. But to understand such things as, what are the tolerances? to understand the implications, before they happen, of controlled and uncontrolled changes in the process, the theoretical understanding is necessary too. When I see the conundrum, where the laminated board is potentially in a higher stress state, you know, I think it is a valid concern. I am not bringing up the effects of the phases of the moon here!

Perhaps not. But I do think you are looking for problems where none exist. And please don’t assume that a lot of thought has not gone into understanding how these things work.

While you’ve introduced a lot of very detailed specifics about the behavior of wood, little of it has anything to do with how soundboards actually work. Inside a laminated soundboard panel, quite frankly, I don’t really care if macro- or micro-cracks were to develop in a perpendicular-to-grain direction. I’ve never seen any evidence that such cracks do develop but, even if they did, they would not affect the acoustical performance of the piano in any measurable or audible way.

I do not pretend to know all there is to know about laminated soundboard panels but I do know quite a lot. Some of this knowledge comes from my understanding of the nature and structure of wood, some my understanding of soundboards in general, and some from my work with developing and testing laminated soundboard panels since the 1980s. I admit that during that time I’ve not given a whole lot of thought to either macro- or micro-cracks developing in the softwood of the core material. Perhaps this is my intellectual failure but, since I’ve seen absolutely no evidence—none—ever—of structural or acoustical failure to these soundboard panels that could in any way be attributed to such internal damage, I’ve had little incentive to devote much time researching that specific aspect of their design. Perhaps I should but for the moment it is fairly far down on my list of priorities. (Unless, of course, someone comes along with a significant contract or grant to fund such a study—that would change things!)

The article I wrote for Pianobuyer was not intended to be an advanced technical dissertation on the subject. It was intended for a general audience made up primarily of people interested in buying an inexpensive piano that will serve their needs for a reasonable amount of time. Pianos using laminated soundboard panels have demonstrated over a period of decades that they can fulfil this need quite nicely. Their track record for both tuning stability and structural integrity are well-proven.

Is there more to learn? Of course there is but when I’m hired to develop a piano in the low- to mid-market range I’m going to recommend that it use a laminated soundboard panel and I’m going to design one that will both sound good and will last for the indefinite future and I'm not going to worry overly much about any potential cellular failure that can only be seen with a microscope that might someday show up. Maybe.

Sometime next year—God willing and the creek don’t rise—I plan to publish another, somewhat more technical, article on the subject in the Piano Technician’s Journal. Perhaps by then I’ll have learned more about them. I certainly hope so. But even there I doubt I’ll be spending much time investigating the possibility of minute cracks in the softwood layers of the core stock.

ddf
Posted By: Olek

Re: Laminated soundboards - 10/02/15 12:34 PM

Here are some common thinking about the tensionning inside the soundboard :

"Of course, the soundboard of a piano or grand piano as stress-free structure is already hard to imagine.

If the panel is not glued on completely within a very short time, then he must be well dried before gluing down.

The uptake of moisture then creates a compressive stress perpendicular to the grain.
And the base convexity is at least partially accomplished by tensioning the surface, and then, when the pressure bar rests on said bottom curvature oriented in all directions, produces a tension.
Nature and extent of the resulting tensions may be very different depending on the applied method .

In the conventional processes however it always results in a more or less uniform distribution of required tensions on the bottom surface but this is not used for the frequency adjustment.
There seems to be so far penetrated only slightly into the consciousness of the piano makers that what you see these tensions in the soundboard are not only static aspects or even as a method needed to preventing soundboard cracks, but they can also be used as a tool for sound design".

The few piano builders I talked with consider the curved ribs method qs inferior, the soundboard being "slow"

I wrote at Strunz and Ciresa asking if their panels are build that way or no, I will let you know their answer.

Besr regards
Posted By: bleak

Re: Laminated soundboards - 10/02/15 04:51 PM

I wonder if the positive attributes of laminated soundboards can also be applied to carbon-fiber composite soundboards.
Posted By: KurtZ

Re: Laminated soundboards - 10/02/15 07:19 PM

Originally Posted by bleak
I wonder if the positive attributes of laminated soundboards can also be applied to carbon-fiber composite soundboards.


I've watched carbon fiber composites try to gain traction in several musical instrument realms, mainly guitars and cellos. They never get past being a niche product. I think one of the reasons is that their harmonic envelope is just different and we like what we're used to. I liken it to LED light bulbs, the package says soft white and 5200 kelvin but it just doesn't look right. I do notice when I spend enough time in my music room which is all LED or daylight cfl's, when I go out to where the lighting is tungsten (about 5,000k) the light looks distinctly dingy and yellowish. I think if what we were used to was CF soundboards, that when we heard a wood board it would sound a little soft and muffled. We would miss the "clank" of the plastic.

I'll add that humans seem to have an affinity for wood that plastic just can't engender.



Kurt
Posted By: JohnSprung

Re: Laminated soundboards - 10/02/15 09:49 PM

Originally Posted by KurtZ
I liken it to LED light bulbs, the package says soft white and 5200 kelvin but it just doesn't look right. I do notice when I spend enough time in my music room which is all LED or daylight cfl's, when I go out to where the lighting is tungsten (about 5,000k) the light looks distinctly dingy and yellowish.


Actually, LED bulbs are typically much better than CFL's, though not as good as tungsten, for color. All flourescents are stuck with the strong mercury green line at 546.1 nm. You can use an old DVD or CD to diffract out the spectrum and see the mercury spike.

The dingy yellowish balance of daylight is because you're here where I am, in Los Angeles. It's the smog filtering the light.

Posted By: Del

Re: Laminated soundboards - 10/02/15 11:53 PM

[b][/b]
Originally Posted by KurtZ
Originally Posted by bleak
I wonder if the positive attributes of laminated soundboards can also be applied to carbon-fiber composite soundboards.


I've watched carbon fiber composites try to gain traction in several musical instrument realms, mainly guitars and cellos. They never get past being a niche product. I think one of the reasons is that their harmonic envelope is just different and we like what we're used to.

You identified the problem with, "... we like what we're used to."

I was able to listen to two large Steingraeber grands at the factory in Bayreuth a year or so back. One was fitted with the normal wood soundboard, the other with a carbon fiber board. They were both, of course, magnificent instruments and there were a lot of similarities between the two. But there were also some differences. I found the differences interesting but I liked both of them. I think many -- possibly not most but it would be interesting to find out -- would have found each of them to be a more than satisfactory instrument. But I also think many -- again, most? -- would have found that they didn't really like the piano with the carbon fiber soundboard once they knew it was not wood.

I do know from actual experience that people who initially really liked how a certain piano sounded when they thought it was using a solid spruce soundboard ended up deciding they really didn't like it all that much once they learned it was actually using a laminated panel.

I'd love to design a test of this just to find out how much our prejudices affect how we "hear" the piano.

ddf
Posted By: Ed McMorrow, RPT

Re: Laminated soundboards - 10/03/15 02:24 AM

Great thinking Phacke has brought to the discussion, I have never though much about internal deformation of laminated panels before. One does see exceptional, stable life from well made laminated panels in furniture. I think we in the industry are used to thinking no cracking, no warping equals no deformation.

The surface cracking I have seen in double veneer face solid core laminated piano parts always seem to be associated with highly figured face veneers. Many times burl or heavily mottled face wood veneers have cracks in them. Over time these cracks telegraph in to the finish.

On old Steinways the tops and music desks were made with single face veneer on solid core. These often show cracking in the veneer and delamination at the cracks. Newer Steinways went to two cross ply veneer faces on each side. These hold up extremely well.

When I was at the Kingsburg Piano factory in Yantai, China recently I brought two 8"X12" laminated spruce samples of the type they use in some of the pianos they make. They are about 8.2mm thick with a single face veneer on each side. The veneer faces measure a nominal 0.5mm on one side and 0.9mm on the other. Both veneers and the core are quarter sawn spruce. The grain angle between face veneer and core is 45 degrees. Both face veneers have the grain in the same direction.

The side of the panel with the thicker veneer is curved up. The relative humidity in my shop was 52% at the time I measured.

I don't know if the asymmetry of the veneer thickness is typical of all the panels or is part of a normal deviation in production. I don't know if they pay attention to any natural crown the panel may have when they glue the ribs.

I don't know if there is more than one supplier of panels like this.

Hopefully Del has more experience with this and can fill us in. I certainly appreciate his sharing his experience with us.

I prefer to think of the standard solid spruce soundboard with ribs and bridge as a three ply structure. The role of the bridge in forming/accommodating crown is very significant in my experience to the tone quality.
Posted By: Gregor

Re: Laminated soundboards - 10/03/15 08:55 AM

Originally Posted by Del

I was able to listen to two large Steingraeber grands at the factory in Bayreuth a year or so back. One was fitted with the normal wood soundboard, the other with a carbon fiber board.......

....I think many -- possibly not most but it would be interesting to find out -- would have found each of them to be a more than satisfactory instrument. But I also think many -- again, most? -- would have found that they didn't really like the piano with the carbon fiber soundboard once they knew it was not wood......

....I'd love to design a test of this just to find out how much our prejudices affect how we "hear" the piano.


During a Steingraeber factory training I played both grands you mentioned. We were 12 collegues and there was consensus that one grand sounded much better than the other. After that decision it turned out that the one which sounded better was the one with the normal wood board.

Gregor
Posted By: Del

Re: Laminated soundboards - 10/04/15 02:17 AM

Originally Posted by Gregor
Originally Posted by Del

I was able to listen to two large Steingraeber grands at the factory in Bayreuth a year or so back. One was fitted with the normal wood soundboard, the other with a carbon fiber board.......

....I think many -- possibly not most but it would be interesting to find out -- would have found each of them to be a more than satisfactory instrument. But I also think many -- again, most? -- would have found that they didn't really like the piano with the carbon fiber soundboard once they knew it was not wood......

....I'd love to design a test of this just to find out how much our prejudices affect how we "hear" the piano.


During a Steingraeber factory training I played both grands you mentioned. We were 12 collegues and there was consensus that one grand sounded much better than the other. After that decision it turned out that the one which sounded better was the one with the normal wood board.

Gregor

What was it that caused you to prefer one over the other?

ddf
Posted By: Del

Re: Laminated soundboards - 10/04/15 05:38 AM

Originally Posted by Ed McMorrow, RPT
On old Steinways the tops and music desks were made with single face veneer on solid core. These often show cracking in the veneer and delamination at the cracks. Newer Steinways went to two cross ply veneer faces on each side. These hold up extremely well.

Most of the old three-ply lids I’ve seen had the face veneers laid up parallel to the core panel. Even though these were technically laminated panels the did have a tendency to warp and crack. Why it took them so long to adopt the five-ply construction that was so common to the rest of the industry is a mystery.


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When I was at the Kingsburg Piano factory in Yantai, China recently I brought two 8"X12" laminated spruce samples of the type they use in some of the pianos they make. They are about 8.2mm thick with a single face veneer on each side. The veneer faces measure a nominal 0.5mm on one side and 0.9mm on the other. Both veneers and the core are quarter sawn spruce. The grain angle between face veneer and core is 45 degrees. Both face veneers have the grain in the same direction.

The side of the panel with the thicker veneer is curved up. The relative humidity in my shop was 52% at the time I measured.

I don't know if the asymmetry of the veneer thickness is typical of all the panels or is part of a normal deviation in production. I don't know if they pay attention to any natural crown the panel may have when they glue the ribs.

Most modern laminated soundboard panels—at least those I’m aware of—have their face veneers laid up at something between 45° to 15° to the core. This angle will make a difference in both stability and tone performance. Life is a compromise; we talk about laminated soundboard panels being more “stable” than their solid panel counterparts—and they are—but they are not perfectly stable. A three-ply panel with the face veneers laid at 90° to the core will be most stable but it but it will perform least like a similar piano using a solid soundboard panel. The 45° grain orientation is a compromise between dimensional stability and tone performance. A panel using a 15° grain orientation will be the least dimensionally stable but can be made to perform most like a solid panel.

Even at 15° the panel will still have very good resistance to cracking. Below about 5° the panel’s resistance to cracking is compromised and it won’t be much more stable that a solid soundboard panel. Much like those lids mentioned earlier. (None of these are absolutes and a lot depends on the characteristics of the wood used and the balance between the thickness of the core and the face veneers.)

I’ve not seen laminated soundboard panels laid up with face veneers made of different thicknesses. Unless somebody actually told you that this was a deliberate specification—which is, of course, possible—I would suspect somebody got carried away with the wide-belt sander.

As far as I know all laminated soundboard panels are made with both face veneers lying in the same direction.

An aside—sometimes panels are deliberately laid up in a way that will force in a more-or-less controlled warp. Baldwin made the panels from which they cut their vertical piano tenor bridge blanks out of two layers of maple. Both layers were of equal thickness. When they were glued up one layer would be at a very low moisture content while the other would be somewhat higher. (I don’t remember the exact specification.) The two layers were oriented at roughly a 30° angle to each other. After the panel was glued up and it acclimatized to the ambient climate it would “warp” and form a crown that roughly matched the crown of the ribbed soundboard panel.


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I don't know if there is more than one supplier of panels like this.

Hopefully Del has more experience with this and can fill us in. I certainly appreciate his sharing his experience with us.

There are several but, not reading Chinese, I can’t tell you much more than that.


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I prefer to think of the standard solid spruce soundboard with ribs and bridge as a three ply structure. The role of the bridge in forming/accommodating crown is very significant in my experience to the tone quality.

Except that the bridge(s) lie more in line with the grain direction of the panel. This still leaves the panel/rib assembly unbalanced. There have been a couple of manufacturers over the years that have laid the grain of the panel across the bridges but they—the companies—didn’t last long.

ddf
Posted By: Gregor

Re: Laminated soundboards - 10/04/15 11:13 AM

Originally Posted by Del
What was it that caused you to prefer one over the other?


The sound grin

The one with the carbon board sounds not bad, too. After all it´s still a Steingraeber. But the other sounds just better.

Gregor
Posted By: Olek

Re: Laminated soundboards - 10/04/15 12:29 PM

A highly recognized pianist, now Yamaha artist, that checked side by side the Phoenix and normal Steingraeber, told me he was surprised that the Phoenix (bridge agrafes and other modification) was even considered "better ".

It was so evident to him the classical version was more interesting, more manageable tone essentially.

I think some process add power or sustain, or partials to the tone. They leave then a strong coloration that tend to be heard at all level of playing.

The pianists seem to like pianos that can be driven "wild" playing with saturation level(s).

A similar thing happen with pianos that sound good whatever the touch quality of the pianist.
They can be a little deceiving as they help too much in rounding the tone.

The saturated tone is not always pleasing, too so on some pianos the power input from the hammers need to be lessened.


Posted By: Mark Polishook

Re: Laminated soundboards - 10/04/15 03:29 PM

Originally Posted by Del


I was able to listen to two large Steingraeber grands at the factory in Bayreuth a year or so back. One was fitted with the normal wood soundboard, the other with a carbon fiber board. They were both, of course, magnificent instruments and there were a lot of similarities between the two. But there were also some differences. I found the differences interesting but I liked both of them. I think many -- possibly not most but it would be interesting to find out -- would have found each of them to be a more than satisfactory instrument. But I also think many -- again, most? -- would have found that they didn't really like the piano with the carbon fiber soundboard once they knew it was not wood.

I do know from actual experience that people who initially really liked how a certain piano sounded when they thought it was using a solid spruce soundboard ended up deciding they really didn't like it all that much once they learned it was actually using a laminated panel.

I'd love to design a test of this just to find out how much our prejudices affect how we "hear" the piano.

ddf


This is a great point and some research on it would be very interesting. My limited experience playing and comparing spruce and carbon fibre soundboards at Hurstwood Farm Pianos has led me to the exact same conclusion.
Posted By: Del

Re: Laminated soundboards - 10/04/15 03:45 PM

Originally Posted by Gregor
Originally Posted by Del
What was it that caused you to prefer one over the other?


The sound grin

The one with the carbon board sounds not bad, too. After all it´s still a Steingraeber. But the other sounds just better.

Thanks, Gregor, but that doesn't tell us much. Could you be a little more specific?

ddf

Posted By: Gregor

Re: Laminated soundboards - 10/04/15 05:21 PM

Originally Posted by Del
Could you be a little more specific?


I feared that this question could come up wink

To be honest: no, I can´t. It´s generally hard to express a sound in words. Particularly in a language that is not my first and furthermore from memory. But I remember that the first word that came into my mind while playing was: flat, shallow. Of course only in comparison with the normal wood board instrument. I.e., it sounded well, but the other was more refined, somehow.
Posted By: BDB

Re: Laminated soundboards - 10/04/15 05:29 PM

The problem with any sort of comparison of pianos is that there is so much variation of sound that you can get from seemingly identical pianos, not to mention the variation in touch that different pianists can make on the same piano, that comparing one feature is pretty much hopeless.

Even then, people often do not try. There have been so many demonstrations of what purport to be different tunings elsewhere on this board, but they are always announced, so there are no blind tests of preferences.
Posted By: Del

Re: Laminated soundboards - 10/04/15 08:01 PM

Originally Posted by Gregor
Originally Posted by Del
Could you be a little more specific?

I feared that this question could come up wink

To be honest: no, I can´t. It´s generally hard to express a sound in words. Particularly in a language that is not my first and furthermore from memory. But I remember that the first word that came into my mind while playing was: flat, shallow. Of course only in comparison with the normal wood board instrument. I.e., it sounded well, but the other was more refined, somehow.

I understand. I'm hoping to get an idea of what the sound spectrum might have been like both with the piano you liked and with the one you didn't like. I have a pretty good idea what the standard Steingraeber with a wood board might look like but not with the carbon fiber soundboard.

ddf
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