Steinway Duplex Placement

[Richard Brekne]

Hi Ed.

Yes... well I WAS actually just clarifying the point that in theory the 
duplex lengths are supposed to be pre-determined fractional lengths with 
purposed length relationships to the speaking lengths.... and not trying 
to justify whether or not the system works or not.  My own tinkering 
around indicates to me there is more to the idea then is most often 
heeded credit here on pianotech... but then that's (both points really) 
are completely different subject matters.

It was intended I presume as the patent describes, not so much as an 
overall effect.  Elstewise it is hard to explain some of the refinements 
of the principle that have popped up through the years... most recently 
the Schimmel so called Tri-plex system.  Clearly some folks believe 
enough in the basic idea that they go to great lengths to maximize the 
effect and accuracy.  Equally clearly as you point out... Steinway of 
today and reasonably recent past seems to have placed less weight on the 
exact accuracy of the speaking length to duplex length relationships per 
sé.  But then.... as I said... all thats another discussion

Cheers
RicB


        I wrote:
         > The staggered lengths formed by the Steinway system are
         > >obviously not to scale, so I suppose that the overall effect was
         > >more important than the ratios  of individual notes to backscale
         >

            JD replies:
             > What are you saying!  The duplex lengths are obviously
            intended to
             > be, and are in fact, in a simple numerical relationship
            with the
             > speaking length in order to produce a partial of the
            fundamental.
             > That's why they're called "tuned partials".  <<

     >
    In theory, fine, in practise, not so fine.    I have yet to find a
    Steinway
    duplex bar that will accurately produce partials that are related to
    the notes
    they are on for more than a few of the notes per bar,   the rest are
    wildly
    off.   With individual string rests, it is possible, but with
    precast duplex
    bars, it is more of an average than particularly matched to the
    strings.   To
    have it exact, the notching on the distal side of the bridge would
    have to be
    equally exact, and that just doesn't happen with Steinways.   
       Walk through a dealership and see how well matched the backscale
    pitches
    are to the speaking length. When I last did that, the ratios were
    all over the
    map.
    Regards,     
     >
     >


    Ed Foote RPT
    http://www.uk-piano.org/edfoote/index.html