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GH-1 Rescale

  • 1.  GH-1 Rescale

    Posted 02-09-2019 15:40
    Has anyone who does hybrid scaling examined a Yamaha GH-1 for improvement?  I know that ideally it should get several wound strings in the low tenor to ease that transition, however I'm just wondering if anyone has already made an improvement on one simply by changing wire types and perhaps a few gauges.

    I don't have one ready to be done, but knowing that there is plenty of room for improvement I thought perhaps someone else already has.

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 2.  RE: GH-1 Rescale

    Posted 02-09-2019 18:40
    I am not a rebuilder but am very interested in seeing a demonstration of just this sort of improvement that I understand can be achieved with proper rescaling software and Paulello wire. Your chapter has several folks who are doing this with high end rebuilds. I've been encouraging NEECSO to have such a class but so far nobody's done it. John Schenke (at the last annual PTG Convention) had a small Chinese grand on which different sections of the bass and tenor had Paulello and Mapes wire for comparison purposes.

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    Patrick Draine
    Billerica MA
    978-663-9690
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  • 3.  RE: GH-1 Rescale

    Posted 02-09-2019 19:00
    I've rescaled a GP-1 which is like the lowest of the low Yamaha grands...discontinued after 3-1/2 minutes.

    Brought type 1 down to note 30 plain wire tricords. That worked fine.

    Had Mapes make me some Stainless wound trichords 29-27 which is the end of the long bridge. Evidence was inconclusive down there. I have had small diameter wraps produced competently by other vendors, notably Heller and Grandt. However, that was after this job. Mapes doing a small wrap of stainless (.175-.225mm wrap wire diameter) was not successful. The wires were very noisy with plenty of internal beating. This can happen with small diameter wraps, but, like I said, heller and grandt were successful.  So, as to whether the fix worked...not sure.

    Plain wire to the end even with type 1 will not work...wraps are needed. I did not scale 27-29 as bichords, because I find bichords at the end of the long bridge tonally unsatisfactory on small grands...they tend to quack, with way too active mid partials. Their 10th partials beat wildy in octaves above.

    I do service a couple of G-1's, and frankly though I have to tune that area first, so I can come back several times and tweak, I have gotten them stable in a way that surprised me. The GP-1 was a different story. Board way way too stiff...tough beast.




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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 4.  RE: GH-1 Rescale

    Posted 02-09-2019 20:24
    If my memory serves me well, the GH1 had serious stability issues. I believe it wasn't so much of a scaling issue but a structural issue. Has anyone had issues with this model?
    Roger





  • 5.  RE: GH-1 Rescale

    Posted 02-09-2019 21:57
    Roger,

    Yes, these little things do have serious stability probs, but although I have not analyzed the scale, I have long suspected that it was mostly scaling that brought about the issues.

    For instance, in a piano of that size it was long ago demonstrated that wound bichords in the tenor should be SOP, and many other pianos of that size range are scaled that way.

    Anyway, I was hoping it had already been looked at by someone. When in tune they actually do sound quite good (many of them)...they just don't stay that way for long.

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 6.  RE: GH-1 Rescale

    Posted 02-10-2019 10:42
    There is a class on rescaling using paulello wire at the PTG convention this July. 





  • 7.  RE: GH-1 Rescale

    Posted 02-10-2019 11:31
    I did go to real significant personal cost to bring an Aeolian era Chickering 501 grand rebuilt and rescaled by hybrid Wire Scale Protocols to the Lancaster Convention.

    Switching our very low break point plain wire for Type O and even Type 1 wire types is a very simple way to improve these pianos. Some are better done via rebuilding that allows installing wound tri-chords on type O core.

    John Schienke of J.D. Grandt Piano makes wound strings on type O core. Does a great job. Mapes can do it too, but you must provide the core wire to them. The quality of their fine wounds does vary widely. I think some of their winders pull on the wrap wirre too hard when winding.

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    Edward McMorrow
    Edmonds WA
    425-299-3431
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  • 8.  RE: GH-1 Rescale

    Posted 02-11-2019 16:31
    Yamaha used to sell a conversion kit that added a few wound bichords in the tenor. I installed a couple many years ago. Yamaha has apparently discontinued the kit and the parts department had no idea what I was talking about the last time I inquired.

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    Paul Rice
    Asheville NC
    207-721-2659
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