[pianotech] [CAUT] More Bohemia

Richard Brekne ricb at pianostemmer.no
Sat May 2 17:14:47 PDT 2009


Hi Bernard.

I really don't want to get into making a case for who was first with 
what per sé.  It is enough for me to recognize that others were before 
me when it comes to tuning with the idea of perfect 12ths as a priority 
and not octaves.  I'm really unsure when it comes down to just plain 
listening to the end sound of a piano just how much different your Tunic 
software is with what Virgil ends up with, or what Gary would end up 
with or what I end up with. And, as I said it is here I find the most 
interesting path forward.

I do think tho that in the case of Gary, myself, and you.... we are all 
clearly onto very similar ideas... tho to be sure there are significant 
differences. But lets not over state these. For example... and from a 
purely maths perspective to illustrate what I mean...  you stated in 
your last that 3:1 is not the same as 6^(19/31). This is technically 
true. But the latter does work out to 2.998688889... (:1).  Translated 
to real world mechanics with all the imperfections that implies.... we 
are not really talking about anything different.  In a real piano... 
with real inharmonicity if you take for example D3 and tune its 3rd 
partial to 440, and then tune A4's fundemental to exactly 440 or just 
sooooo slightly less then what the above difference implies... you 
change really nothing in the resulting relationship between A4's 
fundemental and D3's fundamental.  D3's fundamental is a result of 
tuning D3's 3rd partial to 440. So its already fixed.  Tuning A4's 
fundemental to this same 440... or 440 minus the 0.00006297... 
difference 6^(19/31) implies is not even a promile of a cent then in 
relation to that resultant D3 fundemental.

But all this is really academic for my part.  I'd have to actually study 
Gary's article very closely a couple times to completely digest all his 
article intended to convey.  But I am quite certain, and he himself says 
this outright in an email to me, that in practicalities he didn't listen 
to octaves at all when tuning.  Rather he was listening and tuning for 
pure(ish) 12ths and 19ths.  It is this general perspective that 
interested me when I first read it, and that was timed with my 
introduction to ETD's and nearly immediate observation that the 
available single partial ETD's of the time were seriously flawed... a 
stance I maintain today.  They sample a few partials ladders of a few 
tones... predict an expected inharmonicity table for that entire piano 
and off one goes.  All para inharmonicity (which is far more significant 
then we are led to believe) is simply disregarded.  To be sure... this 
approach does yield better results then many tuners can get by ear... at 
least more consistent results.  But it seemed to me at the time that we 
should be looking at several partials at the same time. And I said so... 
which was rebuked by many saying things would get too confusing. A 
comment one could expect from tuners who listen to coincidents at their 
frequencies I might add.  In contrast... Virgil types would immediately 
find something that rhymed here with their thinking..... if first they 
were to equate their thinking into the realm of coincident partials 
instead of the more holistic sound they listen for.  Vertituner came 
out... and it was a definite improvement at least on paper... tho I 
never did manage to get ahold of exactly what tuning priorities were 
applied in the weighting algorithms that dynamically evolve as the 
tuning progresses. 

So I imagined that since we use aural tests that actually emphasis the 
12th as an octave check, which automatically take into consideration any 
inharmonicity and para inharmonicity as well in the case one listens 
holistically, given Gary's writting and a couple other tidbits I ran 
into at the time... that I could simply use Tunelab 97 to impose 
exacting 3:1 12ths on top of a pianos inharmonicity as I have 
described.  And, as you have also found much earlier then I did. 
following a completely different entrance route, this actually does work 
quite well.

My route was empirical  trial and effort most of the way... with a 
minimum of theory involved.  I had no need to look more closely at 
Gary's article at the time... I just read <<tune with 12ths instead of 
octaves>>.  I did run into a very interesting bit about how octaves 
stretch is affected by doing this... something I was pointed towards by 
Jim Colemans review of my initial discussions about this. The area 
between C5 and F6 gets changed stretch wise, while the end stretch 
number of C8 is fairly low... at least by American standards. You end up 
with a stretch that is actually quite moderate....but in some regards 
seem the opposite.  So I plotted this on an Excell spread sheet and 
posted that on a few occasions.  I didn't get much response on those 
postings.

So you see...  none of my work threatens any authenticity issues you 
have.  I really can not answer for what Gary's article means in that 
context as I haven't ever seen the need to draw the needed comparisons 
to form an authoritive opinion... due to the more pragmatic approach my 
own path has been on.

To summarize.... I think it wisest to let you and whomever else is 
actually concerned address those issues if you (and they) feel a need.  
I was clearly last out with any of this and have never tried to claim 
anything else.  But to be honest with you... I'm kind of pleased with 
myself over the whole affair.  Seems my more simple minded approach is 
in line with the more theoretical based paths both you and Gary, each in 
your own way plotted out. Its kind of neat to know that I figured out 
something very cool all on my own... and that it actually worked.  I 
otherwise have no need to take any credit for anything....  I'm not 
interested in such things myself.
But this points to  exactly where we can all bear this further in a 
constructive direction.... namely to forward the whole concept of 12ths 
priority tuning.  And I think a first very important step to take at 
this point in that effort is to quantify in terms of actual resultant 
coincident partials spread how these aforementioned tuning methods 
compare.  And again... I would encourage any of my American colleagues 
that have a few bucks and are interested enough to buy Tunic software. 
I'm quite sure it would be worth the purchase... despite the fact that 
it offers just one single type tuning... or one very specific stretch if 
you like.

Cheers
RicB


 




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