Itty Bitty Baldwin

[Stephen Powell]

Good explanation, thanks Ron

Stephen
-----Original Message-----
From: Ron Nossaman <RNossaman@KSCABLE.com>
To: pianotech@ptg.org <pianotech@ptg.org>
Date: Thursday, 29 March 2001 12:25 PM
Subject: Re: Itty Bitty Baldwin


>You'll want to check out Theory and Practice of Piano Construction, by
>William B. White for better detail, but essentially, speaking length
>progressions in pianos are based on logarithmic progressions - sort of.
>Suppose you wanted a C-8 length of 52mm, with a (semi) logarithmic
>progression to 186mm at C-6. EXP(LN(52)+((88-present unison)*0.0531) will
>get you there. Increasing the 0.0531 figure will make the scale longer, and
>decreasing it will make it shorter. This can be done anywhere in the scale
>with your choice of starting and ending lengths, depending on what sort of
>room you have and the string tensions you want. Note that the last octave+
>of a cheap little spinet can have speaking lengths identical to the last
>octave+ of a 9' grand, but the length progression rates change rather
>dramatically from there on down.
>
>I hope than makes some sense.
>
>Ron N
>