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F. Y. I. What else? Thats why. ENJOY because this Technology I've developed will change the face of pianos forever, and enable all artists to write new piano composition you couldn't do on ANY other acoustic piano no matter the variables, soon I will post the out come of several more pianos that are within a few moths of completion so when the Baldwin 9 foot concert grand roars, that will send the bar of performance thru the roof..

Keep in mind these pianos I'm retrofitting only concludes my reasearch coinsiding with my patents I currently hold but I have certain manufactures that already have shown intrest to create a series of stonetone lines when I haven't even heard the outcome of the new pianos I'm working on now that have soundboards with a full crown and brand new....So I can't wait to hear them myself !! Life is great , Be creative in life it's healthy for the soul

Have a great day


We'll see, 2010's a benchmark for Stonetone to go public after all the R & D

Keith, Thank you for your valuable input, That video was done on a moments notice since we had access to an identical Baldwin as ours with exception of the age difference varying less than 20 years apart, even tho the mics were't the same and so on.

The video served us well for what it was used for but since then our approach on how to make as close a comparison Richard Bosworth suggested to make comparisons like the chopin clips I posted, critics and the like will have something to say no matter whats done, If anyone is close to Naples Florida come listen for yourself. Any day or time would be fine by us.

Thanks again Keith,
Robert Di Santo

Robert, thanks for posting these examples. I enjoyed the sustain and tone of your Stonetone piano.

The results are VERY OBVIOUS to anyone with ANY kind of musical ear. One can hear the difference between your granite-bridge piano and the normal piano, different pianists, recording venues and techniques notwithstanding.

I look forward to hearing more about your invention! Continued success!!

A search of the US Patent Office database shows no patents issued to anyone named Robert Di Santo or Robert DiSanto. Have these patents not been issued, or were they submitted under a different name?

Granite's hardness varies depending on its composition, but is roughly equivalent to that of steel, whose hardness also varies depending on composition. Granite's density is about the same as aluminum, though it's modulus is somewhat less, meaning that aluminum provides greater stiffness. A wooden or aluminum bridge capped with steel agraffes should be able to provide the same mass and hardness at the string termination as a granite bridge. I wouldn't expect one or the other to provide very different tone. Of course, various design elements other than mass, stiffness, and hardness can affect the string termination.

Aluminum and steel are much easier to form and machine, so I would expect that they would provide more options for string termination than would granite. On the other hand granite sounds so exotic.

Roy,

Keep in mind that they are making the entire bridge from granite, not just the cap. It is very massive and stiff. It appears that they are using very fine grain black granite, often used as decorative surfaces and counter tops and such.

I'll be interested to hear a better recording at some point of this bridge design on a newer / better piano.

Don Mannino RPT

Hi Don,

I understand that, and my comments apply to that case. Consider that a string bears against a bridge over a tiny area. If that bearing point is against, let's say, a steel agraffe, the agraffe can then spread the force of the string over a much larger area, at which point the agraffe could then bear against aluminum or a hard wood. Remember that the Young's modulus of granite is not higher than aluminum. If a large mass is one's goal, the steel agraffe could bear against a brass or bronze bridge, both of which are denser than granite and have a higher Young's modulus than granite.

The purpose of my post was to point out that granite isn't really that special. Additionally, it is brittle and hard to work with. I would be surprised if very heavy bridges were somehow just what was needed for improved tone, but even if that's the case, I think there are more suitable materials to use than stone.

You needed to search the application database:

PIANO HAVING DENSE SOUND-ENHANCING COMPONENT

and

AUDIO DEVICE HAVING DENSE SOUND ENHANCING COMPONENT

I wonder how you keep a granite bridge attached to a soundboard, as a grand bounces on its side in a truck? Can you attach screws through the soundboard?

Since impedance matching is important to prevent energy loss, wouldn't there be a nonlinear effect with a very dense material along its whole length? Manufacturers like Baldwin have attached weights to the bass to improve response, but wouldn't it be counterproductive in the treble? Is it both bridges, or just the bass?

--Cy--

The patent application shows screws. To be able to screw into granite, you typically make a hole and then embed a metal threaded insert.

Adding mass does not cause a nonlinear effect, but your point is a good one--additional mass may be helpful in some areas of the scale and not in others. Given that any number of people have experimented with adding mass by using it in selected areas of the bridge, it seems unlikely to me that adding mass everywhere would be desirable.

Many people have also experimented with adjusting the stiffness of the soundboard, so using a stone bridge to make it stiffer everywhere also seems unlikely to be universally applicable.

Another possible issue is the fragility of granite. Like many types of stone, it is strong in compression, but weak in tension. That's why granite can be cracked into blocks quite easily during the quarrying process. A long thin piece of granite such as a piano bridge would be very easily cracked.

As you've noticed, I'm skeptical of the idea, but the proof is in the performance, so final judgment must be reserved until further testing is done.

Greetings everyone. Most of my comments will not be this long but has background in here since this is my first appearing on the scene. The last two paragraphs deal with the subject if you wish to fast forward and skip the backgound data.

Per the request of the inventor of putting granite in musical instruments(Robert Di Santo)I have joined the Piano Forum to help those with questions that prefer this medium to share and talk about the granite enhancement in PIANOS. I have been studying this for more than 5 years and own the only company (Naples Piano Company) that is producing this granite enhancement in pianos worldwide. Currently I will be contacting a lot of the larger city "dealers" around the United States and some foreign countries eventually to start putting our product out there and get feed back from those of you that love piano music and many are experts and frankly see what your valued opinions are. This has been a very interesting and mind blowing journey for me as time and time again I have to rethink what I know and it has changed for the good.

My history and back ground is that I tuned pianos with zero training (other than hearing a blind piano tuner tune our piano at age 13)and started a few years later (since our piano was out of tune then) and it seem to come natural to me. With many good comments from those who I tuned for, I decided to work as an apprentice for a Baldwin Dealer... and so the journey began. At the age of 19 I was tuning on stage for professionals and love the art of tuning. I also learned rebuilding and restoring pianos since that age and enjoy making something beautiful out of an old relic, and bring life into the instrument again. I've played with my dealership on more of a industrial/showroom setting as it seems my talents are ok as a salesman but not polished in that area. I found my notch though and it worked for me.

Concerning this tread and comments of screwing the bridges with metal threads I can comment on that and many many more things. In this study we have tried a variety of ways to do things and are always keeping an open ear to new ideas. We have experimented with different ways to adhere the sound board to the granite bridge and they all work fine. In the end though it will become more of the easier way for the manufacturers to roll them of the assembly line and still hold firm, and that will dictate which method they finally accept as their favorite. My favorite so far is to glue it just like the wooden bridge did but just bond the granite to the wood instead. Many reasons for this as if someone didn't glue it there would always be a point of rattle possible. Screwing is optional... as the glue has proved to us to hold way beyond my dreams, so holding the bridge in place is not the problem, but getting it apart if you ever wanted too is. Although we are still looking into many ways and this book is not closed yet as this is in the R&D stage... although many ways will work we will keep open minds to the special one that comes forth as most prudent.

You will find most of what we do is experimental, and we have asked many experts in their field questions and are open to suggestions as we all make things better with quality information. The piano guild is an excellent example of sharing ideas between those professionals as we each benefit with the discussion. I find these forums to be similar without the investment of actually being a piano tech or dealer so that the public can talk right with the experts and break down the barriers that once existed.

To reply to some of the questions here with our current study (which is always growing) we can glue or screw the granite bridge on to the sound board, although gluing so far has bonded the two to becoming one that screwing is optional since they have bonded so well that it has amazed me. We are still studying this and in the R&D stage so the book is not closed yet as we discover together the future "best way". The manufactures will like one way over another for ease of installation I'm sure, and that will dictate what we/they do.

As far as steel or similar as a bridge... that has been tried in the past by a couple 1929 and in the 60's and it unfortunately failed miserably as it has to do with way more than just getting the signal from point A to point B, although I am not certain of all the reasons yet... I do know that our point of study with granite that it has a lot to do with the crystalline matrix of it and the dense pressure that made it, plus how that transfers the signal in a different form than steel would, but frankly we need a engineer or scientist to nail this one down. We are in the R&D stage and information will come forth as many "have and will" step up to clear things up.

Treble wise the bridge seems to do just what it does in the bass with a large mass of the string, and that is it spreads the signal further sideways (non linear). With a wood bridge you see the signal going more straight down as the majority of the energy is dispelled directly at the spot with little side ward vibrations... but with the granite having a dense material when the energy hits the stone if seems to fill it side ward's also and use the whole sound board to disburse its energy, so we have taken the piercing hurt out of the piano due to this and yet kept the volume up there. You can hear the bell sound of the note and the sustain ability in the treble as it wastes less of the energy in one spot but is like a whole choir surrounding you instead of one person close up singing in your ear.

Putting the two together (stone bridge and wood sound board) has made the strength go up, as the stone helps the sound board to not go down and keep the highly desired crown indefinitely... also the sound board helps the stone to not crack under pressure. It seems the two together are made for each others weakness to make the two stronger than either one apart from themselves. I celebrate the union of the two as a match made in heaven.

The only possible negative that I can think of is that the piano will have a beautiful tone after 50 years when most of the sound board crown's in conventional pianos are decreased and are lacking the beautiful luster... which will keep you from buying a new one if you have stone in your bridge (brand name not important) and be more of a one time purchase for countless generations as long as you keep changing the hammers and dampers as such. So Repeat business seems to be the down fall (if you wish to call that a down fall), although the used piano technicians are going to love the rebuilding of actions for countless generations.

This is a "search" and very revolutionary as we and many more in the future will study this on an ongoing continuation of the known facts we find at this juncture, and it will build from there. It appears we are re-writing the rule book on sound disbursement as so many variable have changed comparing it to just wood.

Hello Keith,

I'm Dan at Naples Piano Company and wish to answer some questions that have come up since you have shown some interest concerning the granite bridges, which as a piano tech I am the one studying and implementing this over the last 5 years with the inventor, so I might be able to shed some light on the subject concerning the piano with the granite enhancement. For many years I was unable to even talk about this with out secrecy agreements and non disclosures but now we have progressed far enough and the veil is lifted as we will be getting the product out there. The inventor is in the stone trade and I have 35 years in my piano trade.

We actually had the reverse affect of percussion. Instead of the piano being more percussive it seems the unwanted percussive part was taken out by the audible sustain. Obviously the hammer hits the string so you do have percussion, but when the volume stays close to the hit volume it minimizes the fall-off and it has the tone still maintaining closer to the hit volume than wood bridges. We will be "playing" with more and less granite to see where the sweet spots are or the desired tonal outcome we desire.

We are in the R&D stage of this invention and I dare say will be for years and years as this is bigger than I could have ever known as new things just keep popping up and amazing me.

I am just now in the stage of lining up certain dealers in different larger towns (only one dealer preferable that has vision) to show our piano enhancements and give us feed back as the study continues. The 20 minute presentation on the inventors or my myspace account www.myspace.com/granitepiano (video with the piano picture as the others are just old copyright songs of wood bridge pianos)shows the first piano we did. This granite enhancement here was our first attempt at a full 88 note piano and still the only one in existence, although we have 4 following that one now... so we are at the beginning of letting people know what we have and get their input as the first one is always improved upon as we go.

We did things to understand the technology better and show a progression of it as we go. An example of this was the bass bridge on this Baldwin Grand has a wooden shelf with a granite cap while the other bridge (treble) goes down to the sound board. The reason for this was to try the bass note side by side and show a wood and granite combo bridge against the straight to the sound board granite bridge sound, and you can do it side by side with the joining notes and see what you like better.

This is a study and not just about making every piano the most perfect at first, but more of understanding the limits of stone and wood when we use them in different areas of the piano then the final mix will be put together and be perfected and usable to the manufactures. I have had to keep an open mind throughout this process and throw out what I thought would happen to actually see what really did. The future will be interesting and I look forward to your comments.

Just curious - how did you discover that this bridge "fills it side ward's", compared to wood bridges having "little side ward vibrations"? Is there something you measured?

--Cy--

Sorry for not getting to this quickly, but I don't seem to know when people respond to my written articles for some reason, and I wouldn't have caught this if the inventor of the granite technologies didn't asked me today to keep up on this and check out if anyone had questions. I guess I thought an email automatically would generate to alert me, but apparently not.

First thank you for you question. For years I couldn't share the internal workings with secrecy and non disclosure forms needed, but now that we are going to get this in the hands of professionals we are happy to share the mechanics behind what we know on some of this. I find with intelligence's and understanding that we enjoy the response more knowing it is truly working, which supports what our ears are actually hearing.

So first I had to look at what does wood do?
I have had many conversations on a factory level with various professional who have studied bridges and some that actually had on going tests and hands on concerning wood bridges and what really happens, and experiments with hollow bridges versus full wood, or just standard things from laminates versus real chunk of wood, and I got many inputs to understand wood better. Also we had our own studies.

As a tuner for many years I have voiced new pianos to have a balanced sound, and it used to bother me greatly that when the piano arrived (for example "new" 9 foot concert Baldwin with acu-just) which I sold in the late 70's and the last octave or so had many inconsistencies concerning the tone. It would get this beautiful bellish tone and then the next one side by side had a lesser or more normal tone. This bothered me greatly, so I brought in the experts at that time to fix this. In the end it had to do with the bridge not sending the signal at the exact same rate to the sound board on every string through the wood of the bridge, and I was told it was the nature of the beast and live with it. So as with other pianos I had to bring down the good notes to even out the sound by voicing them so the over all octaves sounded matched. It did work, but I had heard the good perfect sound and now we had diminished that be "just ok" only. Customer happy but technician not.

So I learned early on that the bridge sends the signal to the sound board at different speeds (quality) and therefore many corrections need to be done because of that, such as making sure the hammer is in line and hitting all three strings even, and last resort voicing. The speed of course has many variables from piano to piano and brand to brand. The harder wood transferred the signal better and the softer wood didn't. Then another thing I noticed was the bass strings were more sustaining on a wood bridge piano and the treble died out to where you do not even need dampers on the last octave and a half, so with the mass of string going down each and every note since they are thinner diameter wise... and also shorter to follow the scale that way... it made it harder to keep that impressive sustain and volume up on the strings. This is very obvious when we look at just 1 string per note in the low bass and then it goes to two per note in the middle to upper bass. Why would they do that and why not 88 strings only for 88 notes? So as the strings get shorter and thinner the transfer through the "resistive" material of wood showed loss of signal, and the side wards traveling through this substance decreased also the farther we go toward the treble. This became very clear and then we had to go to 3 strings per note to keep up the mass as it kept getting shorter and less tone getting to the sound board. Well not to bore you with things you may already know... I will tell you what really proved it.

In our testing I had deadened a sound board contact of a few notes. With wood this destroys most of the tone because we found it was more linear traveling with most of the signal. Even in speakers the bass bounces around and the treble is more directional. If a bridge comes unglued to the sound board in one area would be proof enough for most that had dealt with fixing this. With stone it didn't register that a sound board area was even missing tone, and it actually produce the sound totally normal using the rest of the sound board skipping over the part that wasn't touching. Wild eh? You can actually tap on a wooden bridge outside the piano (if factory and have one) and the vibration from the source of the tap is lessened on the other end of the bridge (five foot down). With granite stone we found very little vibration loss. The inventor (Robert Di Santo) has tested and made a guitar with a harder quartzite stone and the piano will follow in time with better results also expected as we go up the hardness chart.

Actually sound transfer through a material being harder has been done for years but we just didn't know it or think about it. From a record player using wood, steal, gem stone, or diamond needle... we always choose the harder substance for longevity and clear tone. In railroad track you listen with your ear to the rail instead of the air since you can feel vibrations and hear them better through steel. A motor boat is heard in the water easier and farther away then in the air because sound travels through a harder medium easier and farther and it is simple physics. If that same railroad track was made out of wood the question is how far would the vibration travel? When two aerospace physicists from NASA studied this for us there comment was stone would work way better than wood as it coupled the energy better with less loss and congratulated us and called our bridge a transducer.

This study has fascinated me obviously since or first full prototype keeps sustaining in the treble and I need 8 more dampers past the last factory one because it keeps sustaining the beautiful tone and won't stop in an allotted decay time that is normal to pianos.

Direct answer to the question is you can measure this with computers, feel it in the substance, and my favorite which is the actual note sound to your ears. We did zero voicing of the new hammers and our tone is very even. The stone being so dense does not have the same grain like wood to follow to get from point A to point B, and on a very small scale is exact and uses the sound board as one entity more as the signal is pre-mixed on the bridge which creates less loss of energy as the sound board is producing the same sounds instead of mixing them across grain. Very revolutionary... but the true test is in playing this piano yourself. Our next step is to put some granite enhanced pianos in dealer's floors or concert Halls, and in a month I will be starting just that as we get the public's view point and comments.

I have several Patents pending and are under disclosure until they mature and can't be accessed until that time. The patent that came up is 1 of 2 that cover the guitar entity.

Any thoughts on how what you're doing relates to the crystal soundboard?

Granite in the sound board is not good as a reflector. Although we may use some granite in conjunction in the sound board, in reality it strength is when you go through it not reflect from it. Case in point is to take your tuning fork if you have one and put it in the center of a granite counter top, and you hear almost nothing. Then put it on the middle of your wooden table and you get a lot of sound reflected. The granite bridge we are doing (and other areas) has to do greatly with point A to point B transportation like your car does. We support where wood is strong, and support where granite is strong. We embrace woods strength's but found out we (as an industry) have been using the wood to transfer through it, and on the bridge for optimal transference of energy granite is preferred. Sound boards in wood we support highly. When 2 NASA aerospace Physicists studied this for us concerning the bridge of a piano they said...

"1) it should minimize loss of energy and 2) it should transfer the string energy over a large area of the sound board. Granite is preferable to wood for both of these since it transmits sound with less loss and more quickly than wood."

Hope this helps you understand the reasons why we use granite and the science behind why it is better as the decision is pure physics. Hearing though is the best way to make your conclusions, and we are doing our best to get these pianos in production and out in the hands of professionals so they can make up their own mind about the science and if it works in their minds or not.

The velocity of sound through a material is a function of its density and its stiffness, (Young's modulus). In this regard, granite is not exceptional--it's modulus and density are similar to that of aluminum.

How well a material transmits sound, i.e., how much loss there is in sound energy as the sound propagates through the material, is a function of the material's lossiness. In this regard, granite is quite poor. Strike a bar of granite, and it will just make a clunk. Strike a bar of steel or aluminum, for example, and it will ring (think of a tuning fork). In fact, granite is often used in precision machinery because of its lossiness--it helps prevent vibrations (i.e.,sound waves) that could ohterwise disturb the operation of the machine.

Forgive me for saying it, but many of Daniel Koehler's remarks reflect fuzzy thinking and technical gobbledygook. I read them as comments from someone acting like a salesman.

I'm an aerospace engineer and am capable of making up stuff just like them, too.



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