Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum New Engineering concepts on Piano Sound production

So what was the verdict Robert? How did people respond to the stonebridge experience. Was there some comparative way they could assess the change?

I remember a presentation done at a piano dealers a few years back where he was introducing a new line of vertical pianos which had an open soundboard at the bottom. Several of us techs stood behind a partition as someone went around playing on about 7-8 different pianos and we tried to match what we heard with the pianos listed on a checklist. Most of us were fairly impressed with the piano and it was a really good way to honestly showcase it to us.

My slotted peghead classical guitar produces more "sustain' than my steel string "f" hole archtop
"but" when I attach a small brass "c" clamp to the archtop headstock sustain is dramatically increased
which rivals the classical guitar with open headstock..it would be interesting to see a clamp made of
granite if it would have the same or greater sustain than the brass "C" clamp..

Given the small clamping area of the c-clamp, one would have to assume that you were adding mass, not stiffness to the headstock. The density of brass is over 3 times that of granite.

Emmery,

Our presentation started @ 7 p.m. and ended @ 9:00 p.m. The questions the folks asked were answered in correlation to Dr. Richard Bosworths performance. I also displayed pictures for reference that showed the (patented) internal apparatus that works in conjunction with the facade of the guitars I've produced that had a direct relationship to the bridge pins interacting to the pianos granite bridge.

There were no shortage of questions while every inquiry had several answers for each question directly explaining how, why, and when..

45 minutes before the end of our presentation folks played our prototype piano to get a true perspective while the questions continued as they witnessed several other folks playing at the same time.

The wood bridge comparison piano was a handmade 7' Shigeru Kawai.

This presentation was thorough and informative from a manufacturing level to restoration issues.

There was a full room of folks that left with a plethora of informative facts of the Stonetone® Technologies.

Once this 9' Baldwin is completed, we'll have a better result since were working with a much better quality piano.

With due respect, I don't know that I'd agree with the "thorough" nature of the presentation. In fact, my biggest take away from the presentation was disappointment that there wasn't more thorough scientific understanding behind the product and how it affects the piano. Nearly all scientific inquiry was referred back to comments made by two NASA scientists who were not present and who stated (in quotes provided to us here in this thread) that they themselves were not familiar with the physics of the piano. Several questions received answers that either didn't address the actual question or did so only tangentially. I would go so far as to say most technical questions were left, at best, only partially answered due to a lack of technical knowledge of the piano.

The result of the granite bridge is indeed a marked improvement in sustain (at the cost of tone quality, in my opinion), but the granite itself is incidental after the weight it provides, as any bridge of equal weight would offer similar if not identical results. That granite is "of the earth" offers no benefit in a piano bridge, and plenty of negatives when it comes to mass production and long term care of a piano.

Adam,

You were confused it seems and weren't part of the folks who played the piano afterwards or conversed with Richard Bosworth on any of the performance particulars that were answered pertained to restoration issues etc. like the other folks did. As stated during the presentation, our patent pending application is pending until early spring 2013 so limited information couldn't be divulged @ this time. Stonetone® is here to stay in lieu of any naysayers. Opinions are just that so your entitled to yours and thank you for attending. The piano speaks for itself.

Robert,

Actually I did play the piano afterwards. And I'll probably drop by Pianoforte soon to try it again with less background noise present. Again, I readily agree to the marked improvement in sustain. I do have some concerns about how it affects the overall tone and character of the piano's sound, which is why I'd like to try it again in a quieter setting. I remain unconvinced as to the suitability (chiefly in terms of ease of production, service, and long-term care) of granite for bridge making. Hopefully receiving your patent will allow you to speak directly and at greater length to those concerns.

And no, I wasn't confused. To clarify my earlier comments about questions being answered insufficiently, "it's practically fused to the board" doesn't at all answer the question "what happens in 20 years when the board has changed shape but the bridge hasn't?" "It's not that bad... but it's $30K a slab" doesn't really answer the question of "how practical is this for a mass production application?" (or perhaps it does but not in the way you'd hoped to). And as for my concerns with technical knowledge of the piano, sufficient technical knowledge of the soundboard's structure and function should have been enough to dissuade any further research into granite ribs.

Lastly, I humbly suggest that you find another way of interacting with skeptics than condescension and insults (at least on a message board). If your product is going to have a future in pianos, you're going to need the support of the technical community behind it, and insulting the skeptics (which at this point includes the vast majority of piano technicians) isn't going to help your cause.

You may be too sensitive for this discussion Adam..
Thanks for the laugh, and to those sensitive folks who aren't able to conduct constructive criticism ( which happens) don't bother, because I don't have time to respond to ignorance.
30k for a slab is not what was said.
What was said was that we bonded 2 medias together to acquire the mass needed while we felt using a single mass of 3" thickness would be better but only if we were to do 6 or more bridges would this be applicable and justify the cost.
I think you may need to play the piano many more times to get a grip on really what is happening since Thomas Zoells and Dr. Richard Bosworth both agree this is a revolutionary concept that needs refinement which also was stated during the presentation..

Calling other posters ignorant? Maybe you should leave public relations in your company to others Mr Di Santo.

Ignorance is Bliss Jean don't take it personally, pay attention and you may learn something here.

The bridge ensures a tight connection and optimal transmission of sound vibrations (ENERGY) between the strings and the soundboard.

DURING OUR PRESENTATION and since I have understood the function of the bridge in a piano everyone I have talked with on this discussion calls the bridge everything other than what it actually is. Correct term " Transducer " see below of common descriptions and which one fits this application using stone..





definition of a conductor:

A material or element that allows free movement of electrons and therefore allows easy flow of electricity. Most conductors are metals.




definition of transmitter: 1. a person who transmits
1. a thing that transmits; specif.,
a. the part of a telegraphic instrument by which messages are sent
b. the part of a telephone, behind or including the mouthpiece, that converts speech sound into electric impulses for transmission
c. the apparatus that generates radio waves, modulates their amplitude or frequency, and transmits them by means of an antenna



Definition of a transducer: A substance or device, such as a piezoelectric crystal, microphone, or photoelectric cell, that converts input energy of one form into output energy of another.



Definition of a pressurized transducer: 1) What is a pressure transducer? A pressure transducer is a transducer that converts pressure into an analog electrical signal.

2)Pressure applied to the pressure transducer produces a deflection of the diaphragm which introduces strain. The strain will produce an electrical resistance change proportional to the pressure.

3)
Most pressure transducers feature an accuracy of High stability and high accuracy. pressure transducers can offer errors as low as 0.05% of full scale. Although more expensive than general purpose transducers, they may be the only option if high precision is required.

While it is understandable for you to defend what you've obviously worked hard for, these kinds of responses come across as immature and are not going to win you any friends. Adam has valid concerns, which you are unwise to dismiss, especially since they are shared by other qualified tuner-technicians (including one person on here who actually designs, redesigns, and builds pianos for a living).

While I happen to disagree with Adam about the effects of the bridge being a detriment to tone, I was bothered by the apparent lack of understanding with respect to soundboard physics. Mass and stiffness of a soundboard assembly have immense impact on attack and sustain, and by using a granite bridge, you are adding a lot of both. If you are serious about refining your product, I recommend reading "Voicing the Soundboard with Weights and Riblets", which was published in the PTG Journal in the August 2007 issue.

You should also acquaint yourself with other literature on piano design (specifically soundboards) by Del Fandrich, Ron Overs, or anyone else who has expertise in that area. You need this knowledge if you keep doing these presentations because technicians always ask tough questions, especially if they catch you saying something untrue.

Thank you beethoven986.
I have several sources who have suggested the same as you have and for very good reasons since there will be more presentations in the future.
I am the inventor of the Stonetone® technologies and relize I need to have more perspective on the language used of the folks in these piano forums being I am a jouneyman in my trade than a piano technician.
I work with several piano professionals where they clue me in on pertinent questions as to why and so on.
Thanks again for the informative links.

Pay attention here and YOU will learn something.

Jean, put a sock in it already .. seems you are the one needs knowledge on this topic. Not many folks understand the physics of granite, try the giza pyramids for starters..

Your definition, an uncited quote from WiKi, is incorrect in this application. A transducer changes one form of energy to another. That is not the case in a piano bridge. A piano bridge transmits mechanical energy, vibration, and does not change the form of energy.

It is you sir, who are rude and immature in your insistance to prove others wrong, even though they possess far greater understanding and knowledge of the specific application of a piano bridge.

sir have you played one? thats what I thought. my definition is correct and trumps yours by geological physicists conclusions far more credible than your assumptions. Don't be such a smarty Marty.

Ok I'll bite.

Nah.... changed my mind.

I rest my case.

Our entry level prototype can be seen and played @ the pianoforte Chicago if you need to make your own decision if that is your choice, otherwise these type a comments are moot without the physical prototype in front of you. Good nite