ON PITCH RAISING


Pitch-raising of the last few years has been turned into a bit of a circus. There is nothing inherently wrong with this as there has been much good accomplished in the way of technique, world records, and written words about the subject. What seems to have been neglected is the fact that, for so many of us that go out there day after day to make a living, pitch-raising is no game but a function of our activities that saps our energy and stresses our minds and bodies.

Occasionally, I am tightly scheduled for two or three weeks at a time. When I encounter a piano that is flat, and that I know will not stay in tune and on pitch with only one tuning, I have to work harder to do the two tunings during the same time I had hoped to do but one. What this means is that I have to decide what the fall rate of this instrument will be and raise the pitch to compensate. I must tune the piano well enough so that, when I go through it for the second time, it will require less energy than in a regular tuning, will stay where I want it, and will leave me feeling confident that it reflects the skill I brought to bear.
I schedule four tunings a day: one at 9:30 am (to avoid the rush hour), the second at 11:30 am, the third at 1:30 pm, and the final tuning at 3:30 pm. I allow 90 minutes to go in and do the work required, and then 30 minutes to move on to the next job. If I am unable to do the work necessary during that amount of time, I decide what work can be done and what work can be postponed to another time. I have never deferred a pitch-raise, although on some doubtful pianos I have not raised the pitch at all.
I generally take 20 to 30 minutes to raise pitch and then another 45 to 50 minutes to fine tune. The pitch-raise time may seem excessive to some, but my objective is to finish with a piano in tune that requires a fine polish only for the second tuning – without more rough cutting.
At one time I was tuning so many pianos of one make and model that I was able to pitch-raise them up to 30 cents in 20 minutes and have it in such good tune that it was almost criminal to charge for the fine tune. Few of us tune just one make and model but encounter a wide variety of instruments, each with its own characteristics.
When assessing a piano for a pitch raise, one of the more difficult decisions is what the fall rate of the piano is likely to be. This judgment must take into account several variable factors, each of which will have its influence.
AGE
New pianos tend to be less stable and if they are left a little sharp, all the better for the next tuning (unless standard pitch is a requirement of the job). There is a very large safety factor that permits a degree of hammer swinging freedom. This is, of course, true of pianos that are several years old and have not been tuned since they left the dealer’s floor.
Not-so-new pianos are generally more stable, if you have tightened the plate screws. They have an adequate safety factor against string breakage. Older pianos also tend to be more stable but have a limited safety factor. More care must be exercised so as not to overcompensate. You must be cautious not to overpull the strings because of the loose tuning pins.
STRUCTURE
A solid, heavy, and strong structure will give less and will have a lower fall rate; whereas a light design will be less rigid and require a larger compensation factor. The difference from one extreme to another can be as much as 50 percent. That is to say, if one piano should be pitch raised by 10 cents, another may require 15 cents for the same degree of flatness.
QUALITY
The quality of design and construction is a factor that is not always related to structure. Some very fine and expensive pianos have a fairly flexible structure as an element of their design, so a larger compensation factor needs to be used. Other high quality instruments are very rigid and the use of a high factor would necessitate a pitch lowering.
For many pianos, structure and quality are so closely related that a one-to-one relationship nearly exists. It only remains for you to make an estimate based on your experience and observations of the structure (plate, back, rim, case, etc.) and its quality (engineering, workmanship, materials, etc.).
FLATNESS
The amount of flatness is the factor that is going to have the greatest influence on your work approach., In the C4-A4 region, 1 bps is equivalent to about 5 cents. In most cases, 8 is the outside limit for a nonpitch-raise and, even at that, tuning instability creeps in so that a pitch raise would be necessary for a concert situation.
The maximum limit that a piano can be raised above pitch is about 40 cents. Pitch raising any more than this on new strings risks approaching the elastic limit and destroying the long-term resilience of the string. With older strings the risk is breakage. A piano that is 150 or more cents flat will require three tunings, and if it is a new or restrung piano, maybe four.
CONDITION
Cracked plates, pinblock back separations, extreme age, severe corrosion, and severe abuse are factors that would prevent one from attempting any tuning. The worst cases aside, a tightened plate, reasonably free moving strings, a degree of care and caution, some understanding of the limits, and a few technical points are the basics for experience leading to proficiency in pitch raising.
The usual fall rate for the average piano is 25 percent of the degree of flatness. By adding or subtracting one or two percentage points for each of the listed factors, one should be able to arrive at a compensation factor close to what is needed for a good job. When a piano is found to be flat, check the C4-E4 or the A3-C#4 third (depending upon which fork you use) to make certain that the beat is about what it should be. Tune your reference note (C4 or A3) to the fork and check the third again. A pure third indicates 12 to 13 cents flat, and a third that sounds right but contracted indicates about 25 cents flat. A half tone is easy to determine (as is a quarter tone, 50 cents) by comparing the reference note to the adjacent note upward.
If a 10-year-old (+1 percent) studio piano (+1 percent) in the 3000-pound-Sterling (-1 percent) category is of medium weight (+0 percent) and of a basic good design (+1 percent) but is 20 cents flat, I would use 25 percent (with nothing added or subtracted) as a compensation factor and raise my C4 to 5 cents sharp so that I have either a 1-bps beat with the fork or so that the beat of the C4-E4 third is just less than halved. I would then tune a good 4-minute temperament and start tuning the treble, giving each octave a little extra stretch.
If the piano is in rather good tune but just flat, I will stretch the octaves about one-half beat per second; however, if it is below pitch (most are), I will put about one-half beat per second in each octave as I go up until I reach the C5 region. Here I will use a little more stretch until about CB, at which point I start to taper off until the CB octave is tuned pure.
If it is an American or European piano, I will pull in the bass so that the octaves are tuned when slightly contracted (just enough so there is not a discernible beat) and then I will pull in the middle unisons. (I use a temperament strip only in the middle section.) If it is a Japanese piano, I will pull in the middle section unisons first and then tune the bass as above.
At this point, I will begin the fine tune. I pitch raise a little slower, but my aim is a better end result, which is – after all is said and done – the purpose of it all. It really doesn’t matter how one goes about it, but time and effort conserved is well earned.   
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