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Paulello wire

  • 1.  Paulello wire

    Registered Piano Technician
    Posted 16 days ago
    I have been fascinated reading a recent thread discussing the use of Paulello wire particularly in the tenor sections. If if I understand correctly, the Paulello wire is higher tension than Mapes or Roslau? I wonder if those who have installed Paulello wire notice any difference in pitch stability in the low tenor compared with the above brands?
    My reason for this question comes from observation that low tenor plain wires always react more to environmental changes than the wound wires (higher tension?) located side by side on the bridge. When plain wires are the only ones on the tenor bridge, I observe that the lowest wires are the most affected by environmental changes.
    Anyone care to comment?

    Joe Wiencek
    NYC


  • 2.  RE: Paulello wire

    Member
    Posted 16 days ago
    There is no difference in tension between the different types of Paullelo wire and Mapes or Rosalu of the same diameter. The tension remains the same.

    The Bp% changes.

    I almost always use Paullelo types 1 for a few notes in the low tenor and type O up to the mid alto. The lower tensile strength type 1, when appropriate according to the BP% reading, will be more stable, and, in my experience, the tone will be superior. My low trebles are consistently some of the nicest parts of my scales, tone-wise...this is in numerous pianos or different makers, and over a number of years. PLus, very often, it eliminates the need (not always, though) for wrapps in the low tenor, which I try to avoid as much as I can. I want to hear plain wire trichords down there.




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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 3.  RE: Paulello wire

    Registered Piano Technician
    Posted 16 days ago
    Joe,

    So it turns out that there is an optimal range in the tension of a string/wire in which it vibrates "better" than in other ranges. If I'm not mistaken, this "Goldilocks" zone is in the general realm of 40% to 60% (sometimes a little more) of the tension at which the wire would otherwise break.

    Ideally, the scaling should progress with higher and higher tension as the notes get lower, and the wire gauge gets larger. However the reality is that since the length of the wire has a limitation as the notes get lower, therefore the tension to achieve the proper frequency must be reduced.  This results in suboptimal tensions in that part of the scale. But since the goldilocks zone remains the same these notes with suboptimal tension are often very much out of the "zone" particularly because our modern wire is actually significantly stronger than the wire of 100-140 years ago, making the goldilocks zone even harder to achieve since it is a % of the breaking strength of the wire.

    Paulello wire is made in varying "strengths" therefore changing the relative % of breakage, making it more possible to get these suboptimal tensions back up closer to, or into the "zone". So it's all just a matter of relative strength of the metal making it closer to the type of wire prevalent when the pianos were designed and scaled.  The notes sound better, tune better, and stabilize better under these conditions.

    HTH,

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 4.  RE: Paulello wire

    Registered Piano Technician
    Posted 16 days ago
    Peter,
    Thank you for the metallurgy lesson. Very interesting to note the difference in wire strengths of now compared with when a lot of wire scales were designed.  

    Joe





  • 5.  RE: Paulello wire

    Registered Piano Technician
    Posted 16 days ago
    Thanks for clarifying that bit about BP % Jim. I realize I didn't think very carefully about the tension and wire diameters before posting the question. Is it the increase of mass in the wrapped strings that contributes to them being more stable through seasonal or humidity changes (compared with their neighboring plain wires?)

    Joe





  • 6.  RE: Paulello wire

    Registered Piano Technician
    Posted 15 days ago
    Try this as a thought tool:

    1) As the wire comes closer and closer to its breaking point, its behavior becomes closer and closer to "perfect;" i.e. the inharmonicity approaches zero so that the wire can convert the chaos of displacement into a perfectly harmonious sound, and it requires relatively greater changes in tension to produce a noticeable change in pitch. [Imagine inharmonicity as "harmonic disagreement" in the moving wire.]

    2) Now reverse the idea and compare it to what you experience in the lowest plainwire notes: As the tension of the wire drops further and further from the breaking tension, inharmonicity increases, the sound becomes weak and erratic as the "harmonic disagreement" in the wire behavior becomes greater. The wire cannot co-ordinate its partials in a way to move the soundboard vigorously and musically. The perceived pitch of the note changes noticeably with small changes of tension.

    There is a range of % of breakpoint tension which gives a familiar "piano sound," and reduces the chance of wire breakage to minimum. Historically, people have accepted surprisingly awful sound at the low tenor break. I don't think 1920s Steinway pianos were any better about this than they are today. Bechstein produced a 5 foot piano in the 1920s with a plainwire B2, dreadful sound, but if you tune carefully the owner doesn't seem to notice because they are used to it.

    Paullelo wire is the first practical solution to this problem, and the results are stunning. Visit Paullelo's website to learn more. It has a spread sheet with which you can analyze and calculate the best possible Paullelo scale for any piano.  <http://www.stephenpaulello.com/en/cordes>

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    Ed Sutton
    ed440@me.com
    (980) 254-7413
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  • 7.  RE: Paulello wire

    Registered Piano Technician
    Posted 15 days ago
    To add to the good work above I would like to point out that the Paullelo wire is all the same alloy of steel but it is the annealing process that differs. The lower strength wire types are annealed more to make them softer.

    In Jim Ellis's book on L-mode he compared same size wire samples of modern wire and the no longer made Pure Sound stainless wire. The measurements showed the L-modes were lower in stainless wire and of less magnitude. Paullelo wire was not available then.

    This suggests to me and my unmeasured ears that the tone improvement from using Paullelo "soft" wire in the low BP sections of piano scales is due to reduced L-modes. I think L-modes can "distort" T-modes when they mix at the bridge so reducing their strength is a bonus.

    The modulus of elasticity of all the types of Paullelo wire is the same. This should mean the inharmonicity is not affected by annealing. In my early practice of Hybrid Wire Scales, I used Pure Sound wire in the lowest BP sections. I did notice a slight change to the beat rates expected from the higher inharmonicity low BP produces.

    You can also use Paullelo soft wire for cores on wound strings. This opens up a wide range of scaling options the industry has never had before in any organized way.

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    Edward McMorrow
    Edmonds WA
    425-299-3431
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