String coupling.

[Richard Brekne]

Roger Jolly wrote:
> 
> >
> 
>            At least you restored my sanity, well the little that I never
> had. I have also noted similar results as you have indicated.
> With a new set of hammers, very carefully mated to the strings, I have
> noted that the partial pattern is very different on the centre string, by
> single straight line needling up the cup line to pop the cup and then re
> mating, similar patterns were obtained on all 3 strings.

Interesting... do you use the Pianalyser to check each string individually
to do this ??


> The ETD unison will now both show  and sound correct. The only conclusion
> on my part is that the ear is a remarkable instrument,  in that it can
> compensate in a manner that is amazing, when dealing with slightly false
> beats and mis aligned partials.

I personally am convinced that if ETD would provide us information about
more then one partial at a time (as in 3 or 4) we could learn an awfull lot
about this process. You might try an experiment that will quickly show one
of the great weaknesses in present ETD's Take tunelab and after doing your
temperament tune a series of perfect 4:2:1 octaves all the way up. You can
do this by setting tunelab to read the fundemental, and select the double
octave up from the lowest note, and zeroing the display on that note. This
then becomes the reference frequency to tune the octave and double octave.
Start with the "reference note" as the lowest note of a single octave
temperament.

As you get up past one full 12 note series of double octaves in this
fashion you of course will start to overlap 4:2:1 double octaves, and thats
where things become interesting. Just keep tuning 4:2:1's to you come up to
the top. Retune any "1's" that were previously "2's) to fit the present
4:2:1. 

When you are done start back at the begginning this time just observing
what tunelab shows for each note. You will notice that there is quite a
weird "curve" if you will caused by all the retuning of the middle octave
notes. You can spend as long as you want and be as accurate as you want.
But dont fudge. Tune "perfect" 4:2:1's all the way.

I'd be interested to hear your comments on this little experiment. And you
can also subject an RCT generated tuning curve and then an aural tuning to
this same "analysis". Food for thought I guarantee you.



> The stiffness of the bridge due to notching, (gut feel tells me, enters the
> picture) although I have no proof in this regard.
> The quest continues.
> Please pass the straight jacket.
> Roger
> 
> Roger Jolly
> Saskatoon, Canada.
> 306-665-0213
> Fax 652-0505

-- 
Richard Brekne
Associate PTG, N.P.T.F.
Bergen, Norway