Hi Joe Thanks. Let me see if I understand you right. You are saying to compare the old scale lengths with the new, determine the ratio of the difference between each, and offset the hammers accordingly ? I suppose one takes the existing strike point on the strings and duplicate that in terms of the ratio of the string length to striking point on the new strings ? Looks to me like the most significant change will be in the higher treble. I'm looking at two alternatives before placing and notching the new bridge. The top string A85 was 48 mm long. A very short scale to say the least. One scenario has that going to 54 mm and the lowest bass string increasing 3 mm in length so as to make possible as smooth a transition from the longer (new) high treble to the tenor section. The other is a much more moderate change keeping the tenor and most of the treble lengths the same, but increasing the top octave lengths a little... with A85 going up to 50.5. In both cases tho it would seem to me that any change in striking point would be most significant in the high treble... yes ? The former of these two alternatives was designed by a fellow who uses a completely different scale program then I've seen before. It uses a parameter called "Harmonicity" (as opposed to inharmonicity). As I understand it is a parameter that uses an idealized inharmonicity curve as a base line and graphs how far off this idealized line the scales actual inharmonicity is. The idealized inharmonicity is based on the scale length as a whole in some fashion I couldnt quite discern. I'd be curious to hear thoughts or of others experiences with this parameter in scaleing design Thanks Joe Cheers RicB RicB said: "Hi Folks. I have a question to put to you all. When one decides to change the string lengths as part of a rescaling endeavor, how does one account for the need to re-figure the striking point for the hammers ? On the surface of it a very modest change in lengths would not seem to require much in the way of changing the strike line.... at least in the bass, but how exactly does one proceed ?" Thanks Ric, I'd check to see what the the "ratio" for the original string lengths were and off-set the new hammer lines to that ratio. I assume most of the new lengths are in the lower end of the piano, so there should be sufficient room to re-establish a new hammer line to the "designed" "ratio". Of course, if you did something really radical, then all bets are off. In that case a lot of compromising would take precedence.<G> Regards, Joe Garrett, R.P.T. Captain of the Tool Police
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