To Bill Spurlock: Dear Bill, In responding to your question about repetition in wippen support springs: We routinely modify Steinways with support springs with great success. Acceptable repetition can be had even when springs are working hard. The limit for balance weight reduction is about 25 grams with the 0.7mm heavy renner support spring. We have balanced actions to a balance weight of 30 grams that repeat very well. It is my observation that wippen support springs work very well with full projection weight hammers and full leverage. The substantial hammer mass requires a stronger rep spring and gives the repetition lever something substantial to push against. The low amount of key lead facilitates return acceleration of the key as well. Were I see support springs not working is in many Korean makes were the ratio seems to range anywhere from 5.5 to 6.5. When the ratio is 6.5, too much lead is put into the key and repetition suffers. David C. Stanwood
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