[CAUT] St. D Aliquot bar specs

[Ron Nossaman]

On 7/18/2012 6:03 AM, Rob Loomis wrote:
> Thanks -
>
> I've got 2 70's D's and 2 brand new D's with so many problems that I'm
> just trying to tack down any original intentions.
>
> My understanding has been that the back string does not send energy back
> to the speaking length but that if those lengths are 'in tune' they can
> help give a more full tone by ringing sympathetically with lower
> partials. Any possible truth?


Anything's possible, I'm told, but since the entire open back scale 
responds to each speaking length in the piano, odds are that something 
back there will be in some sort of "tune" with any note struck. Some 
techs insist they can hear a difference between tuned and untuned back 
scales, while others report that if there actually is a difference, it's 
not worth the trouble to tune them. My thoughts that if the difference 
isn't detectable, it's likely not worth attention, are not widely 
shared, so the tuned rear (and front, for that matter) will remain in 
the mythology forever no matter what.

Consider also that the segment lengths of the speaking lengths and the 
rear duplex are considerably different, and will go out of tune 
differently with any given humidity or temperature movement, so even a 
rear duplex perfectly tuned to it's corresponding speaking length can't 
possibly stay that way for more than a few minutes at best. Also 
consider that the cast aliquots are supposed to accurately subdivide the 
duplex into precise ratios of their speaking lengths, when the speaking 
lengths in Steinways vary so randomly. Strikes me as a system that's 
sure to succeed.

The only real benefit I can see to the tuned rear duplex is that it, as 
Ed Foote said, gives you a last chance means of making bearing 
adjustments after the piano is strung by ignoring the tuning and moving 
them to where they'll do some good in some fashion.

One more. Pluck the shortest tuned duplex length in the piano, listen to 
the resulting "dink", and envision how that will enrich the tonal 
spectrum of anything else in the piano. I sure never could.

Ron N