The proper servicing of a piano has three main aspects: Tuning, Regulation and Voicing.
It is important that your piano is tuned regularly. Manufacturers recommend that pianos be tuned twice a year. The frequency of playing, as well as the effects of seasonal changes, temperature and humidity fluctuations within your home are the major contributing factors in your piano going out of tune.
Concert Pitch (A4 ut pitch– 440 Hertz) is a given tone height which will allow different instruments to play together. Due to negligence and infrequent tuning intervals, pitch can be lost to an extent that your piano tuner will not be able to raise it with just one tune.
Although the pitch of a piano may have dropped, it can still be tuned satisfactorily within itself on a flat pitch. This is not harmful to your instrument. But bearing in mind that your piano was designed to be played on and tuned at concert pitch, it will most likely sound its best at A4 – 440Hertz.
Regulation keeps your instrument in optimal playing condition.
The image at left shows the intricacies of a modern upright piano’s playing mechanism. Also called the action, it consists of wood, felt, leather, paper, cloth, lead, metal, glue, and a variety of adjustment screws. Most of these materials are subject to wear and tear.
Regulation will keep your instrument in optimal playing condition. It entails many different adjustments within the playing mechanism and keyboard and will maintain sensitive touch response. The following is a guideline regarding the frequency of regulation intervals:
Concert/performing instruments: annually
Teachers’ pianos: every 3-5 years
Grand pianos: every 3-5 years
Upright pianos: every 5-10 years
Like tuning, voicing concerns itself with a tonal aspect of your piano, namely the evenness of tone throughout your instrument. It involves:
- Maintenance of an optimal shape of the hammer heads
- How and where the hammer head makes contact with the strings
- The adjustment of resilience within the hammer felt
Photo at left shows hammer heads of different size for bass, tenor, and treble section (click to enlarge).
Maintenance of an optimal shape of the hammer heads
Every time a key is played the hammer head strikes the strings leaving a slight mark on its tip. These marks develop into more pronounced indentations, and over time into increasingly deepening grooves which will deform the hammer head and affect tone quality.
A badly worn hammer head shown alongside one that has been reshaped. By reshaping the hammer head the grooves are removed and the original shape is re-established. Whenever this is done, the hammer heads decrease slightly in size and there will come a time when the replacement with a new set might want to be considered. This will give you many more years of playing to look forward to.
How and where the hammer head makes contact with the string
To benefit fully from the tonal potential of your instrument, it is important that all strings of notes consisting of either 2 or 3 strings per not be struck by the hammer in equal measure.
A maladjusted hammer that is hardly striking the right string. Through playing and/or natural movement within the wooden parts of the playing mechanism, the equal contact of the hammer head and strings may become compromised to varying degrees. Shaping may be required.
The adjustment of resilience within the hammer felt
Different densities within the felt need to be adjusted to create a homogenous tone throughout the instrument.
A well-voiced instrument will allow the pianist to control the whole spectrum between piano and forte playing. A new piano should reach you well voiced by the manufacturer in accordance with the brand’s tonal style. Ideally, after-sale voicing for the client should be minimal.
If installation of a new set of hammer heads is required, the process of factory voicing would have to take place again. This requires expertise.
About the manufacture of hammer heads
Hammer head manufacture is a highly artful craft in itself. Most piano makers source these parts from companies that specialise in the manufacture of hammer heads. These are produced to the exact specifications required by the piano maker.
The shapes and sizes of hammer heads, as well as the angle that connects them to the hammer shank, vary not only from brand to brand to brand, but also within a particular instrument.
Piano makers throughout the world have brought into their work their own ideas of tonal aesthetics, leaving us a diverse history of tonal styles.
These styles also changed over time with the advancements of manufacturing techniques and the refinements of materials.
Tone perception is a sensuous and individual experience. What sounds mellifluous to one person may be unpleasant to another. Therefore, when you chose a piano for its tone, appreciate diversity of timbre and acknowledge that even two pianos of the same brand and even the same model can differ in tone. Listen and compare with an open mind, and find out for yourself what sounds agreeable to you.