Hi Richard: The variations of inharmonicity especially in the lower numbered partials is something which can be seen even in plain wire strings. There are two 7' pianos in which the second partial of C5 is flatter than the fundamental. This is most unusual. More variation is observed in wound strings in general. The most weird thing is found when the copper wrap is over wrapped for about one inch at the bridge end of the strings. This often causes more than just the second partial to be flatter than the fundamental and makes tuning by any means utterly impossible. This phenomenon was witnessed on one of the most prestigious 6' piano in the world. Jim Coleman, Sr.
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