RCT

[Roger Jolly]

Hi Paul,
            I also am one of the beta testers for Dean, my contribution
although small is in the area the spectrum analyser usage, aka inharmonicity.

  Through my studies of inharmonicity, it has become clear that several
factors come into play that can change inharmonicity results in real time.
they are as follows. I have confirmed the PAZ results with a frequency
counter and filters. PAZ now has a frequency counter in the latest
editions, just click on the cents inharmonicity column, it will convert to Hz.

Hammer hardness or elasticity. See the results of my May article on steam
voicing.
Dwell time, the length of time the hammer is in contact with the string.
Jack position and height, this effects the efficiency of energy transfer
from hammer to string.
Phasing, and leveling of strings.

  The point I am making is that aural tuning, no matter how good, is loaded
with subtle compromises, each compromise compounds the errors. Depending on
the notes sampled on an ETD and its harmonic content, will depend on what
type of curve the device will compute.
  On fine concert pianos (being paid premium rates) I sample a large number
of notes for harmonic content and voice accordingly. The harmonic series
crudely follows a parabolic curve in the bass and should smoothly change to
an exponential decay towards the treble.
this is an over simplification, but if you do some samples for yourself you
will get the picture.

  I am always in awe with the top aural tuners, in the way they compensate
for poor scaling, bad regulation and voicing. With the grands that I
regularly service, I take a more holistic approach, minor reg and voicing
with every tuning, and charge accordingly.

  The bass/tenor break is always the bogie man area of most pianos. Let's
exclude sound board impedance since we can't change the board in the field.
String mating, (phasing) is a frequent sore spot, switching from steel to
wound strings adds another dimension. If you service the inconsistencies
prior to tuning, then both aural and ET tunings will be smoother.
What you will be doing is smoothing out the inharmonicity.
It is interesting hearing the reactions from members of the Beta team, all
well respected techs, but all with different taste, for things like stretch
and intonation.
Just think back to the tune off with Virgil and Dr Jim. No real conclusion,
but the tunings were different.
This is the reason that I will offer no conclusions, beauty is in the eye
of the beholder, so to speak.
Separating the tuning, from the condition of the piano is not possible A
perfect tuning is as elusive as a perfect voicing job, I know I have never
achieved either, nor will I ever, but I'll keep trying.
Just my take on the subject.
Roger
>
>Roger,
>
>Sounds like you have done this.  Would be interested to know what you
>found.  I'm still trying to figure out how to get RCT (or any other ETD)
>to agree more closely with my aural tunings.  My stretch preferences
>tend to differ from RCT's, mainly in that I seem to like more stretch in
>the bass and that I tune the intervals across the wound/plain string
>transition wider than RCT does.
>
>However, this is not consistent, depending on the size, scale design and
>condition of the piano (esp. strings and hammers), and occasionally I
>even prefer slightly less bass stretch than RCT does.  I realize that
>RCT adjusts to differences, but those adjustments don't always agree
>with the way I would adjust aurally.  I also realize that I have a
>choice of octave stretches and can vary ad infinitum within any preset
>stretch, but I'm never quite sure what will agree best with my aural
>tunings unless I first do a complete aural tuning and then see how to
>tweak RCT to match it.
>
>Which is what I guess you are suggesting.  However, I would not feel
>comfortable about generalizing about my preferences vs. RCT's without
>doing this exercise on at least several dozen pianos and keeping close
>tabs on the results.  Isn't there an easier way?
>
>I know Dean does this sort of thing all the time and that RCT is based
>on his research.  I also know that he has solicited the results of many
>testers like Don Mannino and incorporated that into his design.  The
>result is impressive and the tunings are very good.  However, they don't
>yet feel as much like my tunings as I would like them to be.
>
>Of course they are much closer to my preferences now than they were when
>I started using RCT three months ago, and I'm sure that my proficiency
>with it will only increase.  But am I missing something that might make
>my tunings conform more closely to my aural preferences without
>investing a lot of research time on my own?
>
>Paul S. Larudee, RPT
>Richmond, CA
> 
Roger Jolly
BaldwinYamaha Piano Centre
Saskatoon and Regina
Saskatchewan, Canada.
306-665-0213
Fax 652-0505