single vs. three string unisons (long)

[FSSturm@aol.com]

Jim,
Thanks for your response. I figured you would have done some careful testing
and analysis before making such a statement. Not having an RCT yet, I can't
try to duplicate your tests, but I am certain they were carefully done. I'm
glad you were unable to detect any evidence using the SAT, either. It gives
me a little more confidence in my ability with that machine.

I'm still not sure that you have really confirmed Virgil Smith's assertion,
however. It seems to me that a phenomenon that can only be measured when the
three strings of a unison are within a .1 cent tolerance is not going to have
much if any practical application. You write that tuning within a .1 cent
tolerance is awfully tough to do. I echo that statement wholeheartedly. I
even question whether it is possible to tune a three string unison so that
all three strings are within a .1 cent tolerance without the help of an ETD.
If you can't get that fine a resolution aurally, then an argument for an
aural tuning method based on a phenomenon that only occurs (or at least is
only measurable) within that tolerance range has little if any basis in
fact/experience.

I still think Virgil is tuning to produce pure triple octaves (maybe even
some quadruple, though I am skeptical, at least for most pianos), and then
checking back and finding that the intervening double and single octaves are
too narrow to fit into his overall scheme, and need to be expanded. Thus, he
chooses to begin by tuning his octaves wider than his ear finds really
acceptable in order to "prepare the ground" for those later triple octaves.
The assertion that this is done because three strings are flat of single
strings is just a psychological devise to overcome the aversion to the sound
of those somewhat too wide sounding octaves.

I don't mean to say that I disagree with that tuning method, or with the
result. I tend to be a bit more conservative in my stretching, at least on
most of the pianos I face, but I may change my mind yet. What I am arguing is
that I hate to see the notion that there is a pitch difference between single
strings and the three string unisons they constitute take hold as one of
those hazy "truths" that tend to be misapplied more often than not. Let's be
clear that if this is a fact, it is only true within very tight parameters,
and is unlikely to affect our everyday tuning.

One thing Virgil's article did for me, and as you write, for yourself as
well, was to get me interested in analyzing the pitch of three strings played
together. (After tuning the first note with the SAT, then tuning the other
two aurally, look at the machine to see what you've got. Or even after tuning
each string individually with the SAT, checking how the three read together).
It has made me a bit more careful in what I accept, and has led me to a
better "reading of the lights". I find that reading the three strings
together often helps considerably in deciding how to interpret doubtful
strings. I'll be quite interested to use the RCT one of these days, to see
how it is different.

I don't mean to be negative. I appreciate your integrity in doing careful
measurements and following whatever results you got, whether you liked them
or not. I just think we should put this in perspective, and if we agree that
there actually <is> a measureable pitch difference between a single string
and a three string unison of which it is a part, we should always footnote
the observation with a statement that it is a negligible one, and would have
little practical bearing on everyday tuning, except under the most exacting
of conditions.
Warm regards,
Fred S. Sturm, RPT
Albuquerque, NM