With respect.... I beg to differ. There are a host of causes for bobbling hammers and ruling out too little jack escapement is very quickly done on an upright. One other point here folks. We dont really have aftertouch in an upright.... not in the sense of the word we use in grands. For many years it was standard to simply not call that after escapement action in an upright <<aftertouch>> at all because it really isn't the same thing. Tho to be sure sometimes the sensation can be made to feel a bit similiar. Still... the key here (in the upright) is jack escapement/clearance. Cheers RicB "Almost all "bobbling hammers" are the result of too little or no aftertouch due to settling of the keys at the balance rail."
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