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Sure internal damping is what strikes me the most when softer grade wire is mounted. I am so used to more conservation of energy that I perceivevthat as a hole in the dwell

With time some hardening occurs.

The damping favour an imnediate stablilsation , straightening the tone, it is not the same effect than comparing bichord and trichord unison, but I appreciate those when enough iH is present, and relate that to low tensionning.

[s]

Ah, so the designers who used the short angled separate tenor bridges were onto something. They heard the odd tones and made accommodation for it, even though they did not know the technical reasons for it. This is a very useful tidbit.

Of course, we are not talking about a characteristic of the piano wire per se, instead we are bringing in a motional characteristic of the bridge. The diagonal crossing prevents or discourages a certain motion in the bridge, thereby preventing the undesireable tones caused by anomalies in the best vibration modes of the strings. Got it. Now come the complexities of supporting a separate bridge and preventing distortions in the sound board, etc., etc.

Oh, what a tangled web we done wove here!

(Sorry to range too far afield, here.)

Sure L mode is present in tone, when i used the "rubbing with rosin impregnated cloth" method to analyze the pitch of the Lmode on a string (so to compute a theoretical Young modulus (?)

I heard what part of the tone it is , it is possibly "tuned" in modern design, I seem to recall a scaling software having a parameter for it.

If you have more information on the quadratic effect, and its eventual relation with Lmode, please let us know.

ALl the best

RESTORE PHIL:
Steinway was very proud of the "scale sweep" they used. From conversations with Henry Steinway he remarked to me that scaling the break took an inordinate amount of time to develop. In my opinion the 3 bridge A's trade off the end of bridge effect against the L-mode. The success of the ring bridge is it counteracts both problems.

I have converted 3 bridge A's to 2 bridge combining a bolt in capo to maintain strike ratio with a hockey stick extension at the bottom of the tenor. I maintain wound tri-chords but designing the hockey stick to minimize rocking is tricky because of the mass increase.

OLEK:
Ellis's book can be ordered from several US supply houses or from the PTG.org website. Ellis was not able to develop an accurate formula for predicting L-mode frequency, the variables because of bridge/soundboard interactions preclude it in his opinion. Conklin and Ellis both have Patents on some aspects of controlling L-mode behavior, but neither discloses a precise formula for calculation that I have seen. I'll get back to you when I think I understand what this "Quadratic effect" and "Phantom Partials" are. Do not think I have ever heard them although Conklin has spectrum analyzer pictures.

Ed, thanks,

How I understand it it occurs audibly above a certain range of dynamics, and then the percentage is eventually strong vs the usual partials.

I tried to have more information and was referred to the AJAS at last to find extracts or resumes.

At stronger force, I perceive a very different tone that is sometime really hidden at more moderate level of play.

it have been said to me that there is reinforcement of partials of course (more hard felt ) , the quadratic effect, different action noise, but also rotations of the vibration plane of the strings can occur.(may be that last gives that strong vibrating move perceived by the pianist at high level of power)

The mass solution perhaps being drill-throughs to reduce the weight?

I hear a voice crying out,

"Pics, please, pics."

well...
That was a lot of information, and debate, nad I thank everyone who tried to penetrate my ignorance.

Let me see if I have got some of this straight.

I was mistaken to think that a stronger wire pulls any harder than a weaker wire in similar notes. The difference lies in how close to its individual breaking point each wire is taken when pulled up to pitch. The weaker wire will be pulled more stiffly than the stronger wire and so produce less inharmonicity. This is called the wire's solicitation.

BDB said that the results of rescaling are subtle. Oleg pointed out that the choice of wire can have a dramatic change; the need to drop two wire sizes in order to keep inharmonicity near original levels. It seems to me that the choice of wire is one of the most consequential decisions to be made in a piano. For fully modern pianos, standard wire is probably fully adequate. But when it comes from pianos built during the developmental era of piano wire, it seems that it is now possible to install either a too hard wire or, equally, a too soft wire and create an inharmonicity curve that is not according to the makers intent. It seems to me that this would change the whole voice of the piano.

All this leaves me right where the firs few posters sent me. I have to investigate the original wire. Breaking strength seems to be the most direct corrolary, so I guess I'm going to build a wire snapper. Any tips on this would be apperciated.

Oddly enough we have just gained access to a full scale Rockwell Hrdness tester( and a man who knows how to run it) Do you think that this type of test might prove relevant?

hi ! do you have pics ?

breaking strain of original wire is of little value , but you can imagine the kind of wire by looking to the lengths and tensions.

I have a spreadsheet allowing to compare the tensions with different type of historical wire, and notation (gauges differ till Poehlmann on European pianos)

I wish you could test modern Roslau wire #15 and thinner, just to verify the breaking strain.

You will have difficulties with a standard Rockwell tester for hardness measurements on music wire for various reasons. First of all music wire is composed of a gradiant of hardness that increases from the center out to its surface. A by product of surface work hardening from the drawing process. Your reading will be in doubt because it will be an average of this gradiant. Secondly, the smallest tip on the gage is ~ 1/16". It will be very difficult to stabilize a small cylindrical surface within the 2 degree perpendicularity required for the test and and typically the most accurate readings are done on flat surrfaces, not radiused ones. The support backing of the wire will need to be a V shaped diamond anvil. Thirdly, there needs to be sufficient metal thickness for the tip to do the initial preload referance indentation and then do the secondary deformation indentation and then to reset on the rebound material for the actual reading. ASTM A228 music wire is rated 41-60 Rockwell C by industry because as the wire increases in size, the gradiant average changes accordingly for hardness.

Go here to get more info...
http://optimumspring.com/technical_resources/materials/carbon_steels/music_wire_228_spring_wire.aspx

For the break strength measurement (much more useful)I would suggest using an appropriate electronic load cell strain gage. It would be best to utilize something similar to a tuning pin coil for the endpoints of the wire on the test. Any knot or small small radius bend point could easily skew the results because these can easily become weakpoints. The loading of the wire needs to be extremely slow and fluid in motion. Any jerky or fast movements would relay spikes on the gage reading.

If your interested in the strength of the wire, I would suggest finding the source maker of the wire and request a copy of their testing results. It seems somewhat futile if you are trying to emulate the wire from a century past or more. That wire has degraded with time and subject to long term creep if strung with tension on a piano.

Back ten years ago I had tested a sample of german music wire by slowely lifting an increased succesion of weight from my weight lifting equipment. The wire deformed and broke within 10 lbs of the calculated point using the calculated information from the above mentioned link.

I was just tuning one of my pianos today, (a 5' 7") which has a "hybrid wire scale". The lowest two plain wire unisons are Pure Sound stainless and the six above are Paulello type O.

I don't use an electronic tuner these days so I haven't pulled mine out to measure partials to see how inharmonic the notes are. But, when tuning I notice that the fifths of the Pure Sound and the type O notes, (the fifth formed has the hybrid wire as the low note of the interval,) have no noticeable 6-4 beating and I know that if I had fully modern piano wire on those note I would hear that little beat at the 6-4 even when my 3-2 matches were perfect. The M3s' also seem quicker. This indicates to me that the inharmonicity of the Stainless and type O wire must be lower. But according to the inharmonicity formula that we use that was derived by Schuck and Young-since the modulus of elasticity of the type O wire is the same as modern piano wire-the inharmonicity should be the same.

Anyone else hear this? If I am hearing correctly this might mean the formula is flawed. I do know that the string terminations affect the calculation and Schuck and Young had to average the differences between clamped and pivot termination. But that difference should only be seen at the fundamental which is irrelevant to our work in general.

I admit to some initial skepticism as well. However, I have tested two varieties of Paullelo’s wire on my string frame and, when compared aurally with strings of identical size and length using Mapes IG wire and Roslau wire, there is a clearly audible difference.

At least there is after the wire has been on the frame and at pitch for a couple of months. It seems to change slightly over time. (I have no explanation for this at the moment.)

I don’t yet have spectrum plots of these tests—my accelerometer preamp decided to stop cooperating with Windows XP a couple of weeks before I started the test—but I’ve had enough verification from other technicians to convince me I’m not just hearing things.

As soon as I can I’ll be getting a new preamp to go with my new computer—don’t you just love how “progress” always means replacing everything and starting over—and I’ll repeat the tests and see what the spectrum analyzer shows. In the mean time I’ve used the same two types of Paullelo’s wire on several problematic bass-to-tenor transitions with reasonable success. It’s easier than converting to bi-chords and, while I don’t find it quite as effective, it is better than doing nothing.

ddf

The Ih lower, on my scaling spreadsheet, when I use less stiff wire. (but the e-modulus is less in the table, possibly it should not(?)

I believe this allow to ascertain the global level of iH beginning with the one at A49 that could be around 0.6 at max for soft wire ,(not too small piano, on verticals it is often more) and that raise much if modern wire is used.

Seem to me that lowering the level of sollicitation the wire is subjected to (changing the pitch) raise the level of iH.

Less iH, more in tune partials, that makes a more brillant tone, at the same time less bodied.

I like soft wire where the lenghts are shortened. seem to me that the energy is adbsorbed sooner when the wire is softer, and that with time some hardening occur that raise the thickness of tone.

Those strings are very stable in pitch and very soon.

Roy123
The difference in using Pure Sound stainless, Type O and Type I wire in the foreshortened plain tri-chords, and in the lowest single and bi-chord wounds as core, verses using fully modern wire is readily heard. The only logical explanation is the difference in how these softer wires propagate and sustain Longitudinal mode. James Ellis's work on L-modes shows lower frequency and amplitude of L-mode in the stainless wire he tested. Paulello's wire was not available then.

I have an article titled "Hybrid Wire Scales" to be published in the PTG Journal sometime after my coming March article titled "Fully Tempered Duplex Scale". There are several Tech's working on these protocols in the US now and for some time in europe. They beat us there. Paulello has done some amazing work.

I tried some 25 years ago the get Mapes to soft anneal select sizes of wire to do some work along these lines-although my thinking at the time was that the inharmonicity would be lower. I seem to be mostly wrong on that prediction. Evidence now shows that L-mode is a more significant source of objectionable sounds than inharmonicity in the piano than previously thought.

I've been playing with this question in my own work...namely, in a full rebuild, am I chasing my tail by correcting scaling problems by redrawing the long bridge & laminating a custom long bridge. Previous to the availability of Paulello and Pure Sound wires, when BP% could only be manipulated within certain limited parameters, yes, the redrawing of the long bridge definitely made sense. But having BP% now as a flexible design parameter, I am seriously questioning my assumption that lengths also had to be addressed.

One thing though that stands out for me in this mental calculus is that the design of the board's structure gets you most of the way there. Blow the structure, and no wire will really fix the problem beyond small hard to detect incremental improvements. But get the board right where it counts, and slight weaknesses in the string scale are much harder to get worked up over. Whatever length generated string scale weaknesses remain seem to be more technician oriented than musician oriented.

So the question I'm working on for myself is, if the board is appropriately designed, and the existing, flawed long bridge and bass bridge are partially corrected with BP% manipulation, are the remaining challenges in the string lengths musically worth the expense of designing and fabricating new bridges...by the way, rather than presenting the above as a statement, this is all a question I'm currently challenging my own assumptions with...haven't decided yet where I am on this...still experimenting.

What I really appreciate about the new wires is the ability to experiment with what the lower tension limits of a modern piano really are, specifically as they relate to small venue/home, fine musician pianos.

Jim Ialeggio

Hi Jim Ialeggio,
I have been thinking the same. Why change a working bridge/soundboard layout. The challenge with the bridge/soundboard is characterizing how they are reacting to L-mode. You can have a decent set of strings regarding elongation etc and be plagued by hoots, whistles and barks that bridge/soundboard modes are influencing.

In my opinion, yes, it is still worth that effort assuming you are already in there, the string frame is out of the piano and you're already doing some amount of bridge work.

Where I appreciate this wire is when not all of that work is otherwise being done. You're not going to fix a GH-1 scale with any of these wires but you can make it less bad.

ddf

I have done many plain trichord conversion to wound bichord back in the day to improve the inharmonicity curve and increase unison tension and string elongation. What these conversions usually do though is change the tone color (thinner more nasal) because you no longer have 3 unison strings coupling. This is readily perceived when you are playing music that has a melody prominent in the bichord region. They also can have louder L-modes that are more reinforced by the rocking bridge motion that can occur.

These new "softer" wires offer many more options to designing a wound to plain transition than we have ever had in the piano industry. Mapes now also offers stainless wrapping in the finest sizes which enables more consistent fine wound strings than is possible with the finest copper wraps.

Skilled piano engineers should now be able to produce small pianos that have exceptional dynamics, tone color and tuning stability, that was not possible before.

Ed
That is an interesting tidbit about Mapes with the stainless. The implications for redesigning small grands are interesting. There might be a possibility of using trichords with fine stainless wraps in the tenor section on some pianos for a few unisons, then go to Type O wire with no wrap for a few more unisons, etc. then resume normal M type wire.

On the same piano, the upper end of the bass might respond to a slightly higher gauge of core wire wrapped with the stainless for lighter loading, but the same tension. This could be an interesting experiment: Since Mapes is considerably less expensive than some of the upper tier string makers, I may order alternative strings for both these portions of the scale on the "Dainty Grand" which I soon to restore. The cost to double up on a dozen to twenty strings, ordering them all at once with two different specs, would be worth the flexibilty.

The tone could be tested with either/or/both to see what tone combination was most pleasing.

Longitudinal mode seems to becoming another buzzword, used without really thinking about what it means. It should mean the elongation and shortening of the string. It has to coincide roughly with the maximal and minimal displacement of the transverse motion of the string. But somehow there are those who would have us believe that it is something entirely separate from other the motions of the string.

All this division into different modes and harmonics tends to confuse one truth: There is only one sound wave coming from a string at a time, which is the combination of all these various factors.

L-Mode originates where there is a localized increase of tension in a string. This predominately occurs at the striking point.

BDB, I assure you I didn't just fall off the turnip truck when it was hit with an L-mode. I have been studying all the literature and running experiments in my shop, and communicating with acoustics researchers for many years.

If you are interested you will be able to read about how I am controlling some L-modes in the March Piano Technicians Journal. It is an article about a Patent I have pending titled "Fully Tempered Duplex Scale".

The work of James Ellis in describing how L-modes couple into and out of T-modes has been very illuminating. I believe that I did play some role in encouraging him to investigate them when we talked about what was known about L-modes in the late 1970's. I lack the requisite electrical engineering prowess to construct monochords with sensitive magnetostrictive transducers. Jim worked at Oakridge Nat'l Laboratories building measurement equipment used for Nuclear controls. He started tuning pianos when he was in high school and serviced them part time during his working career as a scientist. We are so fortunate that someone like him could help us when he retired from Oakridge.

It is precisely how the L-modes interact with the T-modes and the string termination conditions that are very complex and interesting. Mr. Podelsak who did some Piano research that was published in the Journal of the Acoustical Society of America has stated in the past that "much remains to be investigated about the influence of L-modes on piano tone".

BDB, sorry this topic seems to bother you but others seem very interested. It's all just a matter of taste eh?