David,
Another possibility other than the string scale itself is that the soundboard is so stiff down there (and if DB is also high), coupled with short (stiff) back scale on the extreme low end, that the structure is acting as a (high pass) filter.
If she really wants to improve the piano and is willing to spend the money to do so I would pursue the following (in order):
1) Send representative string sample data (i.e., overall length, speaking length, winding length, core diameter, winding diameter) to a recognized expert such as Gregor Heller for analysis. If he says there is huge room for improvement then you have the starting point of your recommendation to the client.
2) If however he asserts that there's actually not much wrong with the scale itself, that it "should" sound great, now you need to look at other things (i.e., downbearing and soundboard stiffness).
3) Or, simply have him make a set optimized for the piano, use German eyes to improve flexibility, Paulello wire where warranted (he knows his stuff), etc. Then when all strings are removed for replacement analyze downbearing (you want very little, if any, in the bass) and make whatever adjustments necessary to achieve it.
4) If all of the above does not noticeably improve the piano then you likely have a stiffness problem in the soundboard and will need to thin it or float it (or both).
My experience tells me that it rarely is just one factor, but rather a combination of factors needing attention. It's not a quick process to redesign a piano.
Peter Grey Piano Doctor
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Peter Grey
Stratham NH
(603) 686-2395
pianodoctor57@gmail.com------------------------------
Original Message:
Sent: 07-05-2024 22:59
From: Steven Rosenthal
Subject: Untunable bass
As Peter Grey suggests, a rescaled set of bass strings might help.
I've had some success, just to get through a tuning, by lightly touching the wire right near the agraffe to kill some of the higher partials and try to work with that.
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Steven Rosenthal RPT
Honolulu HI
(808) 521-7129
Original Message:
Sent: 07-05-2024 22:47
From: David Pinnegar
Subject: Untunable bass
Thanks to all
The lady was slightly confused between going out of tune within a week of tuning and really horrible harmonic mess
Pins were tight enough to all intents and purposes but a couple which were looser or had a visible hole in the keyboard side I treated with ÇA for good measure to eliminate the possibility.
The harmonics were awful. One really couldn't pick out the harmonic series and choosing one harmonic to focus on didn't bring accordance with any other
My diagnosis on stiffness at the termination came through having tried fitting a temporary string with inappropriate windings causing asymmetrical mass distribution along the length. Here the copper must be adding stiffness very close to a point where maximum flexibility should be needed.
So expert opinion here is that not even new bass strings would make the instrument happier?
Best wishes
David P
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David Pinnegar, B.Sc., A.R.C.S.
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+44 1342 850594
Original Message:
Sent: 7/5/2024 9:18:00 PM
From: Wim Blees
Subject: RE: Untunable bass
I don't think bass windings or other fixes have anything to do with the bass going out of tune. If I recall, Toya pianos are not very good instruments. It might just be a structural problem, which can't easily be fixed.
In the mean time, what or how exactly is going out of tune? Could this be a placement situation, like sitting next to a heating/AC vent, or close to the kitchen and/or washing machine?
Wim
Original Message:
Sent: 7/5/2024 6:43:00 PM
From: David Pinnegar
Subject: Untunable bass
Client with Toyo grand complained that her bass kept going out of tune. I tuned it but couldn't get a fix on harmonics. A previous tuner had meddled with a pin leaving the a bushing proud of the plate and there was filing on a pressure bar. Client said I was the third person to tell her it couldn't be tuned…
Going to the other end of the instrument gave the game away …
Would unwinding excess copper be possible or is it simply a matter of new strings?
By the way, as two tuners haven't spotted the problem if anyone here doesn't, it's because the copper is too near the bridge and causing stiffness at the end of the string which needs to flex most
best wishes
David P
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David Pinnegar BSc ARCS
Hammerwood Park, East Grinstead, Sussex, UK
+44 1342 850594
"High Definition" Tuning
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