Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Consequences of a low ring tone soundboard

Sorry I took so long to reply. I have been trying to decide if pianos are stuck as a result of the market being overly conservative and not demanding more from the manufacturers, or if the manufacturers are comfortable making the same product for all eternity. I have received enough push back from people on Twitter that I thought would be interested in advancing piano technology to realize that the real problem may be the buyers and not the sellers. I really like your idea of classifying the instrument as a new kind of piano, possibly targeted to a specific style of music. However, until we hear it, it is hard to determine its best use. If we are successful at liberating a lot of treble content in a deliberate way, we should also be able to suppress it so that it follows the modal density profile of a typical piano. Del Fandrich thought one of the benefits of of this technology is the ability to customize the sound. So, if you want a very mellow tone, we could do that. If you want a bright tone, we could do that. And, in any case, the composite material should at least fix the reliability and longevity issues of wooden soundboards.

From the all-composite thread:

"Modern pianos are constructed using a cast iron frame and steel strings. The coefficient of expansion of the two materials is similar; therefore with change of ambient temperature the tension and therefore pitch in the strings remains relatively unchanged. A piano with a carbon fibre frame would expand minimally with rise in ambient temperature, yet the strings would expand and lose tension and pitch. A compensation method for temperature change had to be devised. The use of carbon fibre in the soundboard reduced the acoustic energy loss in the material of the instrument disproportionately in favour of higher frequencies. The research entailed determination of material quality and controlling energy input to the soundboard at different frequencies. In particular the efficiency of transmission of vibration energy in the strings was found to be so enhanced that longitudinal vibration in the strings became significant and had to be suppressed because it caused unwanted beat frequencies with the normal lateral vibration of the strings."

The shape of the soundboard is dictated by the scale design and string architecture and of course, whether it is crossed or straight strung. The simulation cannot begin until the string architecture is defined. We will cross the strings since the majority of pianos are made this way, and the knowledge we gain from doing this will be more valuable than for a straight strung instrument, which is very rare these days.

I am using a collection of technical papers and patents to define the fitness criteria for the computer. I am a little protective of that information since the design process and outcome may be patentable.

I think that there are many industries and products in the world that can benefit from a fresh approach that isn't constrained by the collective wisdom. As an engineer, I see it all the time. The job I am working on right now will result in a product that is 12X cheaper, 10X smaller and lighter, and has 10X more capability than a similar product from a well established competitor. Our mutual customer is having a hard time believing we can do what we say we can do because all he knows is what our competitor has been selling him. And, that competitor doesn't believe we can do what we say we can do, because his thinking is so structured by his own frame of reference. Meanwhile, we regard it as a relatively easy task. I hope that is what the Evolutionary Piano project can do. People don't ask for more because they don't know there is more. Manufacturers don't make a better piano because of low demand and a limited frame of reference. Del Fandrich and David Rubenstein are the voice of experience on this project. I guess that makes me the wildcard.

I am not sure I understand your last comment. You may have misunderstood something I posted before. Extra low notes require extra long strings to sound good. David Rubenstein followed that mantra to its logical conclusion, a 12 foot piano. And, it is awesome!

Sorry I was not thinking of that piano (but another that have only one size of plin wire all along if I understand well) .

It have a low frequency tone, however, little high partials apparently.

Best regards, and good luck for your project.

Not crossed strings are more logical as they allow to avoid the cutting of soundboard resonance in zones driven by 2 elements that can fight themselves. There are 2 persons that are currently building straight strung grands(oval in shape I guess)
The tone on the old straight strung pianos does not have the break, the tone is more coherent all along, and the basses can benefit or more sympathetic vibrations from the treble probably.

From my various other readings it would APPEAR that there is very little space between the patents that Richard Dain has already.
You might well find that your modelling leads to a space that is already covered by Richard's patents.
It is probably worth investing in the services of a patent attorney - sooner rather than later, i.e. before actually building anything.

This comment probably belongs in the other thread about this project, I didn't find it on a quick search and I am a bit pressed for time today.

That is the Alexander Stadium Concert grand by Adrian Mann.

Wow. That is a mouthful. We are planning on using carbon fiber for the soundboard only, not the frame. Although the steel strings and frame expand at similar rates over temperature, the wooden soundboard does not, and changes with humidity levels as well.

I am already aware that we have to address the high frequencies with the carbon fiber composite. This can be done by blending fiber types in certain percentages, lowering the modulus of the resin, and adding damping agents such as micro-balloons that imitate the cells of wood. We have budgeted we rounds of soundboard trials to dial in the damping. If there was a link to the paper this quote was taken from, I would be interested in reading it.

With that said, eliminating the ribs on the bottom of the soundboard is going to raise the modal density in the treble. I don't know if this will result in a sound that is judged to be brittle, or if it will make the treble more rich and interesting. I have a specific modal density curve I am targeting that will make the soundboard perform like wood all the way up into the treble the way wood would, if it could, but it can't. If we succeed in following this curve, i will consider the project a success even if some people don't like the sound. Because, if we can create a process by which the sound can be tailored by adjusting the shape and material properties, we can make a piano sound like anything we want. The that opens up a whole new world of discovery, and a whole new pallet to paint with. It might make pianos interesting again.

Do you have a link to his patents on soundboards? I can only find bridge agraffe patents. Frankly, it would make more sense to keep the technology as a trade secret for a couple of reasons. First, it is too easy to design around. Second, it is too difficult to tell if someone is stealing your technology.

A good reason why testing this with a concert-sized grand piano is a bad idea. The treble stays much the same, no matter what the size of the piano.



Another good reason why testing this with a concert-sized grand piano is a bad idea. If you can make it sound any way you want, you should be able to make a household sized piano sound like a concert grand.

That piano is interesting, but it didn't really impress me with the sound. It might be the way they recorded it.

True, but nobody will get excited about building another 6 foot piano. Crowdfunding is all about creating excitement. Also, in order to move forward, I need to build something that can be sold to fund future activities. To sum it up, a boring piano won't attract the funding in the first place, and won't yield a valuable instrument.

I disagree. Build me a 6 foot piano that I can disassemble and put in my van myself, light and practical, that will hold a tuning well, or even better ... really well.

If it does not sound like a piano, but serves it's purpose really well as an acoustic instrument. Give it another name.

I won't argue and probably will be really excited to try it out.

On second thought, if you can make it 5 feet long and about 200 pounds, I will buy it.

All the best.

The piano which came closest to that ideal was the Lindner grand: 6 feet, light, practical, simply constructed, capable of being moved through doorways by one person without extra equipment. Its drawback was probably not its design, but the failure of the upright Lindner.

Actually, it would be a good design to emulate to test a soundboard, since the soundboard is easily replaceable. You could probably make a dozen of them for the cost of making a single concert grand, with various soundboard designs, find the one that works best, go back and change the rest to match, sell all of them quickly, and use the proceeds to get them into production faster than you could sell a single concert grand, particularly one of unknown pedigree.