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Figure 5. Top: Hammer like those found in a c. 1800 piano; the wooden hammer head is covered with multiple layers of leather. Bottom: Hammers from a modern piano; these hammers are composed of felt covering a wooden core. The smaller hammer head is from a note in the treble and the larger hammer head from a note in the bass. From Giordano (2010) with permission from Ox- ford University Press.
er—a dulcimer is played by hitting the strings with hammers. How- ever, the dulcimer hammers famil- iar to Cristofori were probably just wooden mallets, and the hammers in Cristofori's known pianos were quite differ- ent. Of course, it is possible that Cristofori may have tried using wooden hammers and found them unsatisfactory, but the state of Cristofori’s origi- nal hammers is not completely clear. In any case, at least some of the hammers de- signed by Cris- tofori were very
Modern pianos continue to use felt covered hammers, which are very similar to those used in pianos after about 1860.
Action Design
The part of the piano that has probably seen the greatest change is the action. The action designed by Cristofori was incredibly simple, and some of its aspects can be seen in the modern action. Even so, he would probably be amazed to find that the modern action contains dozens of different parts for each note. We will not try to describe or explain the modern action in any detail here but refer the interested reader to the references for information. A nice animation of the workings of the modern piano action can be found on YouTube at www.youtube.com/watch?v=vFXBIFyG4tU, and drawings of the action for pianos from different eras are given by Clinkscale (1999). Here I only mention some gen- eral features of the evolution of the action.
By about 1760 there had developed two main schools of pi- ano making, one based in London and another in Vienna. The instruments developed in these two regions evolved in broadly similar ways for the strings, etc., as described in the previous sections. However, the two schools developed two very different action designs that came to be known as the English and Viennese actions. The English action eventu- ally evolved into the design that is now found in virtually all modern grand pianos (and it maintained that name, even though its final form was due to a Frenchman). In the Eng- lish action, the hammers are all mounted on a rail that is above and not attached to the key lever and the rest of the action. The key lever only pushes on a series of other inter- mediate levers to set the hammer into motion. The Viennese action was quite different with each hammer on an axel that was mounted on its corresponding key lever. Both action types had their proponents and were favored by different makers, but eventually the Viennese action was phased out by around 1900.
Pianos for the Home:
Design of the Upright Piano
Our discussion has so far focused entirely on the grand piano. Early piano makers after Cristofori also developed a more modest instrument intended for the average home. An example of the first "home" instrument is shown in Fig- ure 6. These were called "square grand pianos" even though the case was really rectangular. This shape for the case and the layout with the strings running roughly parallel to the keyboard are similar to several types of plucked string in-
different from those that came later. In one of his pianos he mounted a thin cylinder of parchment on a wooden shaft with a layer of felt on the side facing the strings (Pollens, 1995; Giordano, 2010). These hammers seem quite fragile when compared to the others shown in Figure 5. By 1750 until the mid-1800s, piano hammers consisted of one or more layers of leather glued over a wooden core (Figure 5). There is some evidence that Cristofori experimented with this design too.
After about 1850 the hammer design changed to using lay- ers of felt instead of leather (Figure 5). This change was probably made for two reasons. First, the increase in string tension meant that more durable hammers were needed, and the limit for leather was probably reached. Second, the technology for fabricating felt with a very consistent and re- producible density was only developed in the early to mid- 1800s. While felt was available much earlier, this advance in fabrication methods made it then usable for piano hammers.
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