The 4.44" is correct for Steinways only. Other action type havedifferent geometry so the spread action will be different. To determine the optimum spread action is not difficult. Crefully measure up and down weight of a few keys and then increase spread action. DO the same going in the opposite direction. The best spread is that which creates the smallest different between up and down weight. It is far more likely that the capstan is mislocated, but this can only be determined by using Stanwood's formulus. Also check to see how many weights are in the keys, especially in the bass. If there are only two weights there is room for more. If there five or more then you do indeed have a geometry problem. COmpare the relocation of the new and old knuckles. Newton nhunt@jagat.com
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