C88 length, was relevance of bridge pin spacing

Ron Nossaman rnossaman at cox.net
Tue Jan 1 10:46:30 MST 2008


> The nominal C88 standard for the Hamburg D used to be 53 mm. They appear 
> to have reduced their C88 length to 49 mm in their latest iterations 
> (since at least 2000). I'm rebuilding a circa 2000 piano at the moment - 
> in which we're completely re-scaling the treble sections.
> 
> Their latest Ds are heavier in the hitch plate area (which I prefer), 
> and the scale is fully revised to be shorter than previously, but still 
> does not conform to an accurate log-style scale. While overall it looks 
> to conform more or less to log style, there are significant note to note 
> variations. The breaking percentage with the new scale is even lower 
> than previously at note F21. So I don't suppose we can expect to see a 
> scaling improvement in the clones any time soon.

Wonderful... advancing to the rear.


> I also note that some piano 'designers' have been known to shift the 
> front pin row instead of the back pin row, to avoid intersection 
> conflicts. They should be referring to some basic piano-design 101 rules 
> here. The disastrous effect this practice has on tunability and 
> stability should be more than obvious.

Yamaha moves the entire unison in some models, maintaining the 
row spacing at the expense of the length progression. I 
haven't taken a scale from one of these, so I can't say what 
it does to tensions and break%. As I recall, it's done at a 
wire size change, so the tension changes may be minimal.
Ron N


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