[pianotech] Clarification on P-12ths

[Richard Brekne]

Hi Bernard

As per your request here is a brief recount of what Andrés visit to 
Bergen around 2000 had to do with my own P-12th journey.

André was here doing the first of his now well known hammer replacement 
seminars. Not that he'd not done classes before, but this seminar was my 
concept and one that he has developed and refined in the years that have 
passed since then. I'd replaced a set of hammers on a Steinway C and 
balanced them ala Stanwood more or less, and he was to do a regulation 
and voicing seminar. We had 6 participants and 3 days if I remember 
correctly. 

Naturally in the course of such a seminar tuning discussions come up, 
and indeed in one of these André did talk about the major 6th - double 
10th tests for dealing with treble octaves.  And the context was indeed 
octaves.  No mention of 12ths was made and no mention of you or anything 
to do about you was made. This method for getting nice treble octaves 
was one of several tossed back and forth by the participants and nothing 
was really new to anyone. After all... this way of approaching octaves 
goes back a long ways for whatever that is worth. 

It was a timely reminder for my part as I was already on the P-12ths 
path and looking for an alternative to the single partials ETD's 
approach. Indeed I got into quite a spat with a couple folks at the time 
because I'd suggested that the single partial approach available at the 
time was limited at best. I'd already started using Tune-lab to direct 
reference several octave coincident pairs in effort to simulate a kind 
of multi-partials ETD. Rick Baldersin's book had a lot to say on both 
octaves and other intervals tests... including the 12th.  I'd been 
reading in old journals at the same time and bumped into a few articles 
of interest that were also relevant to the 12th interval.... so quite 
naturally I used Tune-lab to simply impose a pure 3:1 12th on a piano to 
see how that would work... and I reported the findings here on pianotech 
and on CAUT.

I remember Ron Koval (I think it was)  immediately shot a hole in my 
first attempt at a 12ths temperament region pointing out that I'd simply 
taken the 19th root of 3 and increasing each successive note from and 
including D3 to A4. The hole was obvious enough... it resulted in a 
straight line instead of the familiar curve.  So I devised a way of 
using Tunelab 97's tuning curve editor to address that.  I tuned D3 and 
A4 to 440, then D4 to a 6:3 octave with D3 and A3 to a 6:3 octave with 
A4, and aurally adjusted the both A3 and D4 so that their respective 
5ths against D3 and A4 were ok to my ear and that their relationship 
together as a 4th was also ok. I then manually sampled the resulting 3rd 
partial of A3, D4 and A4, accepted the 3rd of D3 as 440 entered these 
values into TL97 curve editor and used Robert Scotts then so called 
quadratic interpolation to generate a curve. I had to make three curves 
actually and combine them as the editor only accepted 3 values at a time 
for this. I then expanded this in similar fashion so that the final 
curve was from D2 to F6. 

Now to what degree André can be said to have influenced me in this whole 
process I can not say beyond saying that he told me nothing really new, 
but that combined with all the other things I was reading, thinking 
about, doing it was just one more bit piece that encouraged me along.  
How much one can trace any of this back to your influence on André is 
not for me to say. But in this indirect way, it must be acknowledged 
that through the grapevine you may have indeed created a ripple effect 
that reached my shores.  To be truthful with you tho... I'm quite sure I 
would have headed here anyways.

Personally, I'd say that if you had influenced André in this matter at 
some point, then that fact speaks more to your standing as a respected 
technician in Europe in general then it touches on this issue, and in a 
far more meaningful way... and you have much to be proud about. Both 
Mensurix and your PureOnly tuning software have gained significant 
degrees of respect over here and it should be just a matter of time 
before at least PureOnly starts selling stateside as well... which I 
would encourage and look upon with satisfaction.

Now... I hope you will retract your longstanding accusation that I have 
consciously stolen this from you and admit the obvious, that my own 
P-12ths journey was quite independent of your own, if not completely so 
in reality and that we can once and for all put this side of the whole 
subject matter behind us.

Cheers
Richard Brekne