As a piano tuner, I apply stretched tuning whenever I tune by ear the fundamental frequencies of the higher strings to match the overtone series of the lower-to-midrange strings. I do this on-the-fly without consulting a manual as to how much to raise the top octaves and lower the bottom octaves -- it is all done by ear.
As such, I tune in order to make the piano sound "natural" to my sense of hearing. Restated, if one hears the higher notes to be out-of-tune with the lower notes' overtones ... by virtue of using an electronic tuner to dial in the so-called correct pitch of any given high note -- then by definition that high note will sound "flat" in pitch even though it is tuned independently of the other notes.
I apply only enough pitch stretching such that the constructive/destructive interference in two simultaneously sounded double- to triple octave notes has been eliminated. Smaller pianos, including grands and uprights need more correction than do longer-lengthed concert grands.
Here is another way I would put this: I can always tell when an amateur tuner (or relatively inexperienced professional tuner) has tuned all of the notes of a piano using only an electronic tuner set to equal temperament without listening to the job he did on the piano! EDIT: In my opinion, if a piano tuner insists on using an electronic tuning device, then he should only use it to "lay the bearings" in the middle two octaves -- and then tune the rest by ear in octaves to the middle notes. End Edit Surely, such a piano tuner may protest by saying, "well, my tuning job matches what the electronic tuner described as being perfect".
Aside: Some tuners feel they need to apply an excess of stretched tuning because they believe it is "the thing to do". This results in pianos whose highest octaves are over-tuned a quarter-tone to a semitone too high! (Don't laugh; this occurs wayyyy too often in my experience!) I brought this point up to a so-called "professional tuner" who retorted, "So what? Nobody plays those high notes anyway!!" I just walked away without arguing with that old fool.
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Now, how does this apply to Pianoteq? Well, since most of Modartt's pianos are concert grands with the exceptions of the Steinway B, U4 upright, and some of the smaller historic pianos, I believe the stretch tuning slider is more of a "cure without a disease", a nicety! Why? try playing any two of the same notes approximately 3 octaves apart and listen for constructive/destructive interference in the overtones. If you don't hear anything out of the ordinary (which I DON'T generally hear), then no stretching adjustments are required!
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Regarding harpsichord strings and the need (anti-need) for stretched tuning: The strings of a harpsichord are extremely thin in comparison with corresponding notes of a piano. Therefore, the end conditions of inharmonicity (the resultant boost of higher frequencies of the various overtone series) usually does not play a part in the sound of the instrument. EDIT #2: In addition, harpsichords do not boast 7-1/2 octave ranges of modern pianos; therefore, their limited number of octaves also preclude what little inharmonicity effect there is in their strings. End Edit #2 If you were to adjust the Pianoteq slider -- to the point that stretched tuning becomes noticeable to your ears when playing the same note 2 to 4 octaves apart -- then you have gone too far. So, simply do not apply that amount of stretch to the tuning!
My two cents EDIT #3 (cents in terms of money rather than cents as a fraction of a semitone). End Edit #3
Joe
Last edited by jcfelice88keys (20-10-2018 04:41)
