This is the apt question and quite right, Jim.
I am a piano technician not a scientist. So somewhere between theory, experience, and assessing variables based on exagerrating them to a logical extreme, a la Chris Robinson regulating class analysis, is my defense.
I have found frustration in trying to unscramble the tonal (and mechanical) mess I find in a lot of pianos. With the developing of my tools came a means of at least comparing variables to accurate references. I found a fair amount to correct in my own work, which I had considered to be well-executed and had tried my hardest to make "perfect". Making the parts actually work vertically seemed to be a battle that could be undertaken. I come out of a pragmatic school of piano technology, but I hate fighting against myself in my own work. So here are a couple of streams of logic I have decided to go with rather than fight (or ignore).
First of all, I try to frame it "to the extent that" because where is the point at which a given factor is hidden in the margin of error and where can it be clearly identified? On the other hand, accumulated error has clearly been a problem for the regulator and the voicer. And the piano/bench-imperfect-match conflict is a battleground where we have fought against and often given in to the problem.
So one logical question I ask myself is, if I can do something about something, why should I continue to suffer the annoyance of it?
If you have seven things that might be at fault in a situation and three of them can be named and corrected, why not just do it?
And if something is below the radar of what I can measure but I logically think it's not right, do I consider it not to matter? What if it's clearly in concert with other things not right?
To specifics. If one side of the crown of a hammer has less felt than the other, does it interfere with the integrity of the hammer in how it performs. And if the variation is variable from hammer to hammer, is it a voicing issue?
If you have a hammer that tilts a few degrees, is the loss of power to twist a voicing problem, or a mechanical problem? When does traveling funny or bouncing funny become problematic? There are numbers of questions like this that don't have good answers at the same time that plenty of pianos don't measure up to hoped-for potential.
So working the other way around. Instead of proving they are problems of significance in a particular hammer with a particular voicing shortfall, how about just taking care of the potential problems as globally as possible with matter-of-fact, easy-to-execute protocols.
My results have been significantly better since I have taken this attitude. I spend less energy deciding which things to deal with and which things not to deal with, and move faster through grooming out the known suspects by procedure.
If you really twist over a hammer and extreme file it to mate level strings, you can see where the weaknesses of that approach might lie.
If you really travel something to the left, you can picture where the stresses are going to be and imagine the travel pattern back.
From another tact, if you dry fit a hammer and play it fortissimo at varying degrees of off-vertical, best vertical will be a noticable improvement.
The whole business is complicated enough that I feel it is worth considering what the pure form of what we are after might look like. I think it gives us a better shot at coming closer to the mark more of the time. It's hard to prove a very small error, but it's easy to feel, hear, and be bogged down by accumulated error.
But, point well-taken. It was great to be a recipient of your good organization and great Utah hospitality!
Thanks,
Chris
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Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
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Original Message:
Sent: 03-12-2012 16:43
From: James Busby
Subject: string leveling
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James Busby
Mt Pleasant UT
801-422-3400
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Hi Chris,
I know you to be very exacting and "correct" in these sort of things, but do you have any evidence that the below statement is true, or is it a theory? It seems to me that if the hammer is properly mated by filing it would be hitting the 3 strings with the same force and not a "skewed bounce", and then all the other things, wear, lost energy, etc. wouldn't be an issue, except with una corda use. Of course I'm not talking about huge string leveling problems, but the "normal" everyday concert hall matings which are usually fairly small.
Thanks, and it was great seeing you at WestPac.
Jim
<<<<The skewed bounce produced by misleveled strings (or misfiled hammers or non-vertical travel), however, even if hammers are well-mated, will impact reset, wear on centers, speed of repetition, energy lost to stress and wobble, and mating in the subsequent strikes of repeated notes.
Chris>>>>
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Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
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Original Message:
Sent: 03-11-2012 22:13
From: Norman Cantrell
Subject: string leveling
When Fred mentioned that the goal was to "get the strings into a plane" he hit upon a very important point. Keep in mind that the thing that drives leveling strings on a grand in the first place is the Una Coda pedal. If the hammers did not shift from side to side when this pedal is depressed the mating process would have similar options to those of a vertical. While the ideal is to get the strings level if the top of the hammer is filed in the same bevel (ever so slight) as the beveled (ever so slight) string plane you will still get good mating in both the rest and shifted position(s). I once encountered a situation in vertical piano where there was a slight divot in the V bar causing the center string to be out of plane with the outside strings. No amount of bending would remedy this particular offensive note. The solution I came up with was to actually shape the hammer into a slight "V" that allowed for mating and cleaned up the tone considerably. Mating is paramount to good voicing and making a slight compromise in the plane of the strings is acceptable.
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Norman Cantrell
Piano Clinic
Lawton OK
580-355-5003
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Original Message:
Sent: 03-11-2012 16:38
From: Fred Sturm
Subject: string leveling
I taught a new class on these subjects at West-Pac, called "Focusing the Hammer on the String." It includeds procedures for both uprights and grands. I'll attach the powerpoint (converted to PDF) and handout for those who are interested.
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Fred Sturm
University of New Mexico
fssturm@unm.edu
"The true sign of intelligence is not knowledge, but imagination." - Einstein
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