>What causes the changes in inharmonicity that, over time, can result in the >two members of a bi-chord becoming very discordant? ------------------------------- >Robin Blankenship Hi Robin, My first guess, with the qualification that the two strings were a good match originally, is corrosion. Two fairly widely dissimilar metals in contact in the presence of an electrolyte will corrode. The steel core is the more electrochemically reactive of the copper alloy/steel combination, and with enough room humidity, will rust slightly over a period of time. The changes in stiffness, density, friction between copper and steel, and between the copper wraps will alter the partial structure of the string. The strings don't necessarily both change at the same rates and in the same manner, so they become harder to tune together, and to anything else, as time goes on. Trichords are at least half again as bad (more, in my opinion), as bichords. That is, if you can get strings made so a wrapped trichord is tunable in the first place. On further consideration, I think that's my second guess too. Ron N
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