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"Nor am I asking anyone to do any expensive, difficult, and inconclusive work to try to prove claims that I make, like so many people have asked me, like Mr. Truitt." -BDB.

Let's see - you have never heard or used hybrid wire, but you have already decided that the results will be "inconclusive"? Can you say, confirmation bias?

As for difficult, I thought you already know how to change piano wire, but I guess I was wrong. I'll be happy to type up some instructions for you and send them along. I would even be willing to send you some lengths of different wire to you for free.

Sheesh, you browbeat us for not doing the hard science, but refuse to do it on your own.

I have a different view than you regarding Ed's intellectual property. My understanding is that Ed's process is something that has evolved and been the result of some hard thinking over a period of about 30 years. I don't see his end result as having been a small undertaking. You should also know that it is a significant investment of time to set up for and implement FTDS in a piano, although I am sure Ed is much faster than I am at this point.

It has always been my way to share my own ideas freely with other technicians, that I choose to do of my own free will. But I am also quite happy to compensate Ed for his intellectual property. His fee is nominal, and I can assure you that he has been quite generous with his time. He's a good dude.

Just for the record, I too have heard and isolated v bar noises, which are quite common. String noise leaks past the v bar into the duplex section, and it goes away when I put my finger on the offending duplex length of wire. Imagine that....

Will

As a person of science, I learned long ago that even the most thoughtful testing methodology misses some variables. As a result, it is difficult to prove that that any single change in a test/design (e.g., shape of capo bar) is the single reason why the results changed. In the act act of reshaping the capo bar, new portions of the alloy are exposed - unevenly - as is the nature of an alloy. The string replaced on the newly shaped capo bar can never be at exactly the same tension or physical placement. The time it took to make the changes causes minute changes in the whole of the piano due to age, temperature, humidity, dust, etc.

And the most important change of all - We expect to hear a change, so we do.

All this is not to say that, on average, making changes in scale design, hammer weight, string terminations, and such like, do not change the sound. They do change the sound. Why it changes, however, is not easily provable.

IMHO, Until some form of as yet unknown testing method, free from human bias, is devised, no claim that a single change to a single part of a piano is responsible for the resulting change in sound is good science.

BDB,
So when I encounter a piano with string buzzes in the capo section, and I carefully remove the existing strings, reshape the V-bar to a true V-shape, and carefully reinstall the original strings with the result being no more string buzzes; that is still an insufficient proof? Occam's razor my friend. What other explanation is simpler?

Same for buzzing agraffe.

Ed, I have great respect for your work.

But, the better test of what you mentioned above would be to carefully remove and then reinstall the original strings without doing anything to the capo bar. If the buzzes return, then reshaping the capo bar would be the next test.

If the buzzes do not return, then the simplest explanation is not so simple any more. What action caused the buzzes to go away? Did they all go away? Was the partial structure of the struck strings the same as before? Were the strings in fact exactly replaced in the same positions on the capo bar as before? DId the measured downbearing of each string on it's bridge terminations change? Did the twist of the strings at the points of termination change? ...

Prout, I appreciate where you are going with this, but Ed is still correct in his assessment of cause and effect. Many technicians, including myself (and likely Ed) have let tension down on an area in the treble section, carefully removed the wire coils from the tuning pin, and set the wire aside in order. Then they take a file and carefully reshape the capo bar to the desired configuration. They put the coils back on the pins, add tension to the wire, space it, and finally tune it.

In the shaping process, they have also removed the string grooves from the capo bar surface.

This is such common practice with consistent results that there is little controversy regarding cause and effect.

Also, it is the practice of some to move strings slightly away from the grooves to get a cleaner sound, although this is not as commonly practiced. This also works.

I think that it is important to say at this point that we are practicing piano technicians and rebuilders, and not scientists. It does not seem reasonable to ask us to hold ourselves to the same standard as a practicing scientist would. We have other fish to fry. It is enough to know that doing a particular thing will give us repeatable and consistent results. Ideally, we will have a good understanding as to why that is so.

William (and Ed),

I understand completely what you are saying and highly respect the idea that the actions taken produce repeatable results. I am glad they do. Our pianos are better for it. It is also resonable to state, colloquially, that certain effects follow from certain causes, even though the statement would not stand up to rigorous investigation. We often, even scientists, say something is 'true', even though 'truth' is an elusive, unattainable, and ultimately 'relative' concept. They know they are using the word in a colloquial sense.

I apologize for being pedantic. It is a weakness of mine.

prout

Prout,
I understand your wish to make clear the inherent weakness of word meanings. I believe I am as fully aware of the limits to word based thought structures as any one can be. I am also aware that a good portion of the public still carries a desire to believe that Scientists unwillingness to be absolute about truths, means to them that their own "feelings" about what is true are just as significant. The "proof" is in reproducible results. With pianos we can do that.

But as regards my reshaping in-situ as the "proof" of theorem. One also needs to have proven that new strings put on a less than ideal V-bar to "solve" the string buzz problem will solve the problem in most cases---temporarily. (Some V-bars are so flat the new strings will buzz immediately). This is because the bend around the V-bar has not been fully formed. This is why moving the strings sideways works to solve a buzzy bar---temporarily. After very nearly forty years of experience shaping V-bars to a true V-shape, there is no other explanation possible that is any simpler. I still tune the first piano I reshaped the V-bar in-situ and it continues to work flawlessly and it has never broken a string. I have gone on from that first one to shaping something around 400 V-bars over my career so far. Never seen a problem or heard of one from any other tech about the work.

Meanwhile, the piano factories and most rebuilders continue to turn out pianos that have less than ideal string terminations on the plate with the result being the pianos sound less good from the start and most will develop some string buzzes after enough years and the piano wire will fatigue faster in all of them. Not a good state of affairs for a mature industry.

I say to any piano buyer,"would you purchase a piece of complex machinery that has obvious differences visible to the eye in machining of critical features from one machine to the other"?

Thanks Ed, for your keen insight gained from long experience.

I have a question. You mentioned reshaping the V-bar to a more ideal shape. Is it not the case that, after many decades of tuning, the strings will have caused indentations in the V-bar, resulting in less than an ideal shape? I assume this to be the case, but also assume that, starting from the ideal shape, there is some latitude in the ideal shape that the indentations do not completely destroy.

Thanks Prout,
Yes, the strings indent in the properly shaped V-bar but they never produce buzzes. It is the profile of the termination point that allows string buzzes to arise over time as the string bends/deforms around the contact point. They also do this in the brass agraffes. If the string termination point is properly shaped, the string self-machines the exact shape it wants in response to the counterbearing forces/angle. I also suspect some very slight work-hardening occurs at the string groove. The strings will not keep cutting their way into the v-bar like some sort of slow motion cheese cutter. Piano string termination points must be softer than the wire to avoid damaging the wire to the point that string fatigue/breakage becomes a problem.

What is most frustrating to me is that the piano industry has never seriously investigated the engineering of string terminations. I think I am the only one who has done it methodically. I find it depressing to inspect a new piano and find these things still all wrong. And i published a book, have written an article or two, and lectured many times including this material. I have been in several factories and when I point this out they just ignore it. The factory people never really see how a piano holds up over time.

Hi Ed,

This whole subject of proper shape of the capo D'astro V-bar and brass agraffe termination points is very intriguing to me! I have never had the pleasure of reading your book, but it appears that it's greatest benefit is in preventing string buzzes over time... as if it's more systematically guiding the string self-machining and work-hardening process to a more consistent depth, due to the initial pure "V"-shape structure that is formed. A few questions:

1. Does it matter if the portion of the casting of the V-bar has this more ideal shape initially, or is more preferable to performing this machining step after the casting is done? Related question: Are better results achieved with sand-cast frames or vacuum-cast frames or does this not matter?
2. Is this a process that was once known by any of the great makes or scale designers and forgotten after WWII, or is this learning a result of skilled rebuilders such as yourself discovering this? More specifically: Did Golden-Age (or subsequent era) Steinway, Mason & Hamlin, Bluthner, Bechstein, Bosendorfer, Baldwin etc instruments ever contain these features?
3. I'm also curious about the brass agraffes as well... Did any of the above makes ever have more ideal "V-shaped" agraffe terminations? Are any still available? If not, how do you go about shaping these little devils when rebuilding your pianos?

Have you checked with Mason and Hamlin to see if they can restore it? Bösendorfer offers this service. I haven't needed it but they mentioned this service when I toured their factory recently.

Steve
Bösendorfer 170

(Emphasis added)

"Never" (and "always," which goes hand in hand) are usually impossible to prove.

If you use terms like that, I can imagine that the people you are writing off would be inclined to write you off.

Prout--As a technologist and avid follower and reader of science, I appreciate your thoughts. In the subject in question, it might be nearly impossible to conduct a test that would satisfy the most rigorous requirements of science--at least on a single piano over a short period of time.(A double-blind listening conducted by listening to recorded samples of the piano before and after modification might help.)

However, statistical analysis is a valid and often used method of analyzing experimental results. It may be that in a case such as the one under discussion, following some number of pianos over a number of years could yield the information we desire. The experiment would not be simple and would require careful design. Of course, no single piano tech would have the resources and opportunity to conduct such a test. OTOH, it sounds like Ed, by following pianos over an extended period of time, has seen results that suggest his v-bar shaping method is valid. I think the best we can hope for is that more techs will try this method, and that over time its success (or not) will be revealed.

Another avenue to approach the issue would be to formulate a hypothesis as to why the v-bar shaping works. Then, it might be relatively straightforward to test this hypothesis out of a piano in a controlled way.

Thank you Roy123,
I have a hypothesis regarding string terminations on the plate. It is rooted in the concept of pivot termination first occurring in the literature with the Steinwway Duplex Scale Pat. of 1872. It is also rooted in the breakage testing of high-carbon modern piano wire.

So it is the nature of the wire, how the wire responds to the forces it must endure in place, and the way the wire accepts/converts impulse energy into periodic vibration as a result of the hammer strike displacement.

And I and others technicians as well, do shape V-bars to narrow exact pivot point terminations so my observations regarding performance and durbility are agreed upon by more than one person.

Yesterday, a piano technician by the name of Mr. Reggie Hedahl visited my shop. He has been shaping V-bars to a similar shape as I do for quite a few years now. But less years than me since he is 25 years younger. He started doing this without any exposure to my ideas about this. Like me, he came to this conclusion by observing the problems and coming up with a model to solve them.

When I first published my finding regarding V-bar shape a fellow technician relayed to me that a technician/rebuilder friend of his in the San Francisco Bay area upon being told what I was doing remarked that "Shh don't tell anybody".

I think it is well past time to "Tell everybody the news". In this day of very low cost numerical machining, is is so simple for a factory to get this specification perfect every time, no piano should have a less than perfect V-bar. And no agraffe should ever have the string holes wrongly shaped.

BDB,
Glad you have imagination....Imagine if you can.... Imagine no more string buzzes.....it's easy if you can....

Imagine all the pianists.... never hearing strings buzz....you who who who...you may say I am dreamer...... but I'm not the only one....
Shape a V-bar to a V-shape........and the buzz will be gone!

Actually, I imagine all pianists not having to hear that the piano that they spent a significant amount of their savings and income on needs expensive work.

I'm wondering if shortening the contact point of the wire crossing over the V-bar just raises the pitch of the buzz to above our hearing limit.

BDB,
That's exactly my point. We technicians should insist that the factories establish proper specifications for certain common design elements of the modern piano. We technicians should represent the pianists interests. That is part of our job and collectively we have been abrogating our duties.