Hi, DOn, Newton here. Joel is right with what he said. I would add that there is little merit in changing wire size up or down unless you know how that will effect not just tension but inharmonicity as well. If you have a particular problem with a piano it's scale must be evaluated in it's entirity, not just one or two notes. If you replace a set of bass strings from a US string winder you are likely to get a set that is entire unsuited for the piano. Mapes and Schaff tend to leave an inch to an inch and a quarter unwound at the agraffe end. Inharmonicity goes up by the fourth power of the distance unwound. I now rescale all pianos I restring in order to control the inharmonicity, tension, power and breaking per cent. I supply the string winder a table of winding specifications that way I get what I want and any mistakes are mine. The core wire controls inharmonicity more than wrap does, except unwound ends. If you must use a universal (I do NOT recommend it) then you must choose the core wire that matches the core of the original (disregard the effect of hex cores) then if you have a choice pick a matching wrap. If the old string is still there, splice it. A splice in the speaking length of a bass string cannot be heard unless the wrap is damaged. I have peeled back the wrap a few turns to give me room to splace. Splices should be as small as possible. The loop in the bass string should be as small as possible, the loop in the splice wire should be small enough to allow free movement over the wrap. The loops can be bent so that they are at near ninety degrees to the rest of the string. This allows splices to slip togather without damage to the wrap. As to the tone change, you are hearing a loud fundamental or first partial, which is not necessarily the tone intended by the designer. It is especially lacking in higher partials and the tension may be too low and will cause strings hitting each other when played. This is probably more than you wanted to know about strings and their behavior, but it is important to know this and much more when considering changing a piano scale. My best to Ken, Emil and to the graduating class. Newton Hunt nhunt@jagat.com
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