Key Weighting

This post is intended to suggest a possibly lesser known “aid” for tuning the entire piano. Not included in this discussion are such basics as temperament, tuning checks to use, methods of tuning and electronic instruments if one is used. This post will focus on “fine tuning” a piano that is already at the A440 pitch level and in fairly good, even tensions in all sections.

While tuning certain pianos, particularly the older uprights, all of us have encountered certain strings, usually the longer tenor ones, that suddenly start to ring or sound while tuning due to sympathetic vibration. It was exactly this situation that prompted further study and the exploration of these “open” strings as an aid in aural tuning. It was further noted that the more in phase the octave being tuned, the louder and clearer the sing-through sound created by sympathetic vibration.

This article assumes that the reader also understands at least some of the physical characteristics of vibrating piano strings, their modes, partials and inharmonicities.

The principal of weighting keys is to deliberately raise the damper, freeing the string to sound sympathetically as related intervals are being tuned. The louder and clearer the sound of the weighted-open note, the better in tune the interval being tuned. This is the main principle of the system. Primary intervals in key-weight tuning are the octave, fifth, octave fifth and the double octave fifth. We hope to stimulate enough reader interest for many to actually experiment with the use of key-weighted open sounding strings in tuning.

One very discriminate college piano teacher once remarked, “I am more interested in the fifth being in tune than the simple octave.” Of course what she was favouring was really the 6:3 octave tuning instead of using only the fundamentals in tuning the octave 2:1. A good example of “fifth” tuning is in the matching of the fundamental and the fifth in bass tuning which is fairly standard and well known by most tuners.

In regard to the type of key weight used, anything of size and shape, heavy enough to hold any key fully depressed to open the dampers, is fine. It must also conform in size and shape to hold only one key down at a time, including the sharps, without falling off easily. It is also suggested that the weight be felt covered to eliminate the possibility of scratching any keytops.

BASS TUNING USING KEY WEIGHTS

After completing a fine-tuned temperament, extend accurately the first few notes up to the first B natural above (B4)*. The reason for tuning up these few notes is to have in tune the first fifths to weight keys open before starting the bass tuning. For example, the first note of the bass section below temperament is E3. Now place the weight on ...

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Prestressing Approach to Pitch Lowering

 Piano tuning has been established as a specialty occupation for over 130 years. Now, more than any other time in our history, rapid and basic changes in other fields are having massive influences on piano tuning.

In the last decades  we have seen the superfast tuner, the precision approach to pitch raising, inordinately accurate tunings, the advent of inhumanly accurate electronic tuning aids, and a better approach to scaling pianos -just to mention a few.

In the next years, we will be modifying many of our approaches to tuning, rebuilding, and resealing. We will see an ever-increasing demand for accuracy by ourselves, of each other, and by the buying/owning public. Competition will become stiffer - especially for those who do not keep abreast of what is happening and who do not incorporate the new and superior methods.

It is the philosophy and intent of this blog to present the more suitable, the improved, the new, or even the novel way that is in keeping with good craftsmanship and work habits. It is the further intent of this blog that such methods mentioned are in agreement with the best practices of piano-tuning.

PRESTRESSlNG APPROACH TO PITCH LOWERING

We might tend to assume the aural art/science that we practice has not developed much in recent years, but one has to admit that the art of aural tuning is still developing.

In keeping with that thought, let me now outline the procedure I have developed to rapidly “prestress” the scale prior to fine tuning when lowering pitch. Let’s change the wording of the familiar old shoe, “You cannot fine tune an out-of-tune piano,” to read, “You cannot fine tune an out- of-balance piano scale.” Since a fine tuning is also a delicate balancing of the scale’s tension, any rapid method of achieving a close approximation of that balance prior to the fine-tuning sequence would be of great benefit.

Suppose a particular piano is 8 cents sharp (i.e., A442), and it must be tuned to A440 for a concert. The iron plate and the soundboard crown would not be offended, if we lower the pitch of every other note 16 cents (twice the required amount) to pre- stress the scale prior to tuning every note. Carrying this logic a step further... 

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Hammer Technique

When thought is given to hammer technique, consideration must also be given to the various elements that taken separately, may not appear to be so very important; but a chain is made of many links and we all know the weakest one.

The tuning hammer, at first glance seems to be just a tuning hammer - but there are a variety available. The first consideration is its length. The average hammer is 10 to 11 inches long without a head. I have seen hammers as short as 6 inches and as long as 15 inches. The short hammer feeds back information more directly from the pin and has less length for flexing, but requires considerable strength and endurance to operate. The longer hammers provide more leverage but tend to flex, causing poor hand-to-pin communication, and the increased weight bends the tuning pin a little more than desired.

There have been several variations on the standard “professional” tuning hammer - the very heavy hammer turned from a piece of drive shafting which gives considerable weight to the matter, and the impact tuning hammer which has gained favour with some for pitch-raising. (These are experimental or special application tools and do not, on the average, apply for fine tuning.)

Having an extension hammer is not entirely necessary for extending t introduces so much flex that all mechanical advantage is voided through lost communication. Extension hammers tend to flex at the tightening ferrule and the shaft turns in the handle. The only advantage they have is that the handle can be removed for stringing or other special applications. The ideal hammer, then, is one that is about 10 inches long, lightweight, rigid, one-piece construction, and made of nice wood if possible.

I should be talking - the disreputable hammer I use is only 7-l/2inches long, but is extended to 11inches overall for tuning...

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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 ... 

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