---------------------- multipart/alternative attachment Hi Ed, >The lightest key in the world will not return > very fast if the capstan is too close to the > balance pin. That is interesting to me; The fastest returning keys I have ever seen were on an action that had the capstans moved towards the balance rail in order to reduce the action ratio. This action had no lead weights in the keys at all. Instead, the balance weight was adjusted with magnets. The action ratio was approximately 5.3, if I recall. The key return was so fast that many pianists couldn't get used to the feel of the key following their fingers so closely on the way up. Those who loved this piano were for the most part very fast professional players. The lesson learned from this was that some inertia in the keys is required by most players. That amount is however less than one will find in most pianos on the market. >>In order to achieve that, and still maintain the proper >>static balance weight, the action needs to have a low >>ratio geometry. >Is this to say that the high ratio actions will not >repeat as fast? My experience is otherwise. It depends on the hammer weights. If two actions have same weight hammers and the same balance weight, but one has a high ratio, the action with the high ratio will have slower returning keys because the keys will have more lead in them. >>A stiff spring setting will help return the key faster. >I have not found this to be so. All other things being >equal(and within bounds), there is virtually no measurable >difference in repetition speed between a spring that >throws the hammer off the jack when released from check >and one that simply lifts the hammer just slowly enough >that it can't be felt. When the hammer is in check, the spring pushes the wippen heel against the capstan forcing the key up. While the hammer is checked, neither its weight nor inertia can exert any force on the capstan. That first impetus for the return of the key comes from the repetition spring. As soon as the hammer un-checks, its weight takes over and becomes the restoring force for the key to return to its up position. >However, the former makes escapement a clumsy chore for >pp playing. As I mentioned, it's a compromise. >I still maintain that the major determinate in >repetition speed is the height of check. Absolutely true, the less distance the hammer has to move between the check and the string, the faster it can all happen. Vladan --------------------------------- Do you Yahoo!? With a free 1 GB, there's more in store with Yahoo! Mail. ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/2b/4f/29/12/attachment.htm ---------------------- multipart/alternative attachment--
This PTG archive page provided courtesy of Moy Piano Service, LLC