Whilst normally dealing with well behaved concert instruments in best condition, sometimes I do favours for friends. Today's instrument was a nightmare in France - a baby grand by Ruch of Paris. It was only afterwards I learned that it had been given to the friend at Christmas after having been stored unplayed untuned in a garage up a mountain for five years.
I use Kellner universally as a viable alternative to ET for everything. For speed I normally use the CTS5 tuner to set the scale over the central three octaves without any stretch and checking the 7 perfect fifths on each as I go. The lack of stretch is critical so as not to widen the tenor C# to treble F fifth harmonic, as exemplified by the opening chord of the Raindrop prelude. My method then is to tune the bass below with a best fit of octave, 3rd harmonic and 5th harmonics to the relevant scale notes in the middle and tenor octave and the result tends to be coherent, solid and very musical.
But this didn't work on the Ruch. The tuning was all over the place and sounded hideous. Years ago I used to use the shareware version of Tunelab but haven't had need of it for years, my current technique in every other instance giving better results than standard inharmonicity measurements and curves. But newly having the trial version of Tunelab on my Android I thought I'd do the inharmonicity measurements to see what might be wrong and measured every note up to treble C.
The strings are old and weren't cooperative in moving with the pin movement and two broke on me just at the start of the coils on the tuning pins. As the graph shows, the inharmonicity was all over the place.
As an aside, I'm not sure of what the green and blue graphs are on the Tunelab display, so any enlightenment from anyone would be really appreciated.
But I explained to the owner that it was the random variation of inharmonicity which made the instrument not sound nice, and I redid the tuning entirely using Tunelab to navigate the mess as probably the easiest way to get the most acceptable result in the circumstances.
The instrument has had new hammers and the action is in very good condition therefore. But the stringing . . .
Were I to tell the piano's owner that the instrument should have a restring, would a new set of strings overcome the inharmonicity variations? And we certainly shouldn't get the existing strings sent off for patterns for the new strings. How might one specify the new strings appropriately and would they make a great difference?
I'd rather stick to concert instruments ;-) but sometimes one can't evade getting one's arm twisted.
Best wishes
David P
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David Pinnegar BSc ARCS
Curator and House Tuner - Hammerwood Park, East Grinstead, Sussex UK
antespam@gmail.comCall for papers - Seminar 6th May 2019 - "Restoring emotion to classical music through tuning."
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