[pianotech] phenomana - experiment.

[David Renaud]

> 
> The only way it will mean anything is if it is done as a master tuning by a test committee on a piano previously tuned by a test committee as a master tuning at a significantly different RH%, and the recorded tunings compared.
> 
> Ron N

That can be done also, Two master tunings at two times of year, different humidity levels.
It's alot of work, requiring 3 people for two days time span. 

But I am still interested in meassuring inharmonisity samples seasonally for myself. Easy to collect that data starting immediately.  And collecting data with verituner will also show if the actual harmonics are changing or not.  This will prove if the harmonic content of the piano is or is not changing with seasonal fluctuations in the board, and resulting changes in stiffness.

   Since aurally we do actually tune to those harmonics it would change how we tune aurally the same piano in different seasons. 

   A story to illustrate. The first time I ever took the tuning exam I failed.  The examiner had told me I had tuned using F3 as a reference not F2. I asked how he knew that? Because I had tuned it 2.1 cents flat, compensating exactly for the amount that the first harmonic of A 4 was sharp, 2.1 cents. A4 is not in F3's spectrum it was coincidental an octave higher, and I was compensating for the inharmonisity exactly. I retried the A for Jack, using F2, and put it at 0.0 cents. I could tune beats well but was listening to the worng harmonics with a wrong technique.

      The point is if the harmonic was 2.5 cents instead of 2.1, I would have compensated 2.5 cents, if in the winter it does change and it was 1.8 cents, I would have compensated 1.8 cents. When we tune aurally we are following what the actual harmonics are doing weather we listen to one, or a blend, when they change, we change what we do.

       Therefore, proving the harmonic structure of the sound changes seasonally would very strongly suggests the master tuning would change also. It then would have to be tested aurally on the same master tuning twice as suggested. 

         I don't book exam teams to give a whole day for free lightly. In that interest I prescreen candidates to make sure they are ready to have a good experience in the exam room.
Reading measurments of inharmonisity samples, and verituner data is like prescreening before 
Booking 48 free hours .....up to 8hrs times 3 people twice. 

          Seeing positive data on the inharmonisity measurments, and the verituner results would support the hypothesis although not prove it. Still it gives some confidence that the bigger investment of time producingTwo master tunings on the same instrument is a good use of time.
48 hours is allot for me to expect other to give on a hunch.....I'd like to pretest the hypothesis first
For a strong suggestion it is true. 

                                                   Dave Renaud