| When a key on an acoustic piano is pressed down, | | | | expected from the hammer. |
| the resulting sound continues for a considerable time | | | | It will be remembered that the key has two |
| after the press of the key has taken place, and stops | | | | mechanisms depending upon it, namely, that for |
| when the key is released and allowed to rise. This | | | | producing the tone, and that for stopping it. As long as |
| elimination of sound is caused by action of a second | | | | the key is held down, it is doing a part of its work, as |
| piece of piano mechanism, called the damper. The | | | | soon as the key is allowed to rise a change takes |
| dampers are small pieces of wood with felt attached | | | | place and the tone stops. |
| to them. | | | | It has been already shown that the work of the |
| This mechanism is so connected with the key that the | | | | hammer is completed at the moment of the stroke. It |
| latter cannot be moved without occasioning a | | | | must therefore be the work of the damper which the |
| movement of its own damper. Each key is thus the | | | | keeping down of the key is instrumental in furthering. |
| means by which both a hammer and a damper are | | | | As opposed to the hammer's work being finished as |
| moved to action, the hammer for producing tone, the | | | | soon as the key is down, the work of the damper is |
| damper for stopping it. (In the case of a few of the top | | | | not completed until the key rises. The work of the |
| keys of the piano, the damper mechanism is wanting.) | | | | damper is to stop the tone; and as that stoppage |
| The damper lies constantly touching the string, except | | | | cannot take place until the string is re-touched by the |
| during the holding down of the key, when it is removed | | | | damper, which touch cannot take place until the key |
| from its place and kept off the string as long as the | | | | comes up; the work of the damper is therefore not |
| key is held down. After a pushdown of the key, if the | | | | finished until the key is allowed to rise. |
| key is kept down, it will be noticed that (1) the hammer | | | | The positive action of the hammer takes place when |
| resting at its half-position and (2) the damper removed | | | | the key is pushed down. The positive action of the |
| from the string. When the key is allowed to rise, the | | | | damper takes place when the key is released and |
| hammer falls completely back, and the damper returns | | | | allowed to rise. The negative action of both hammer |
| to the string, and, by touching it, stops the tone. | | | | and damper, namely, their leaving the string, gives the |
| If there were no provision for the stoppage of tone, | | | | latter freedom to vibrate after the stroke. While |
| the effect of any performance would be the same as | | | | therefore both the hammer and the damper begin their |
| that produced when the right foot pedal is held down | | | | work at the same moment, they complete it at |
| during playing. The putting down of the pedal causing | | | | different times, the hammer instantaneously, and the |
| the removal of all the dampers from the strings, and | | | | damper not until the piano key is allowed to rise. |
| creating in consequence the effect as of each | | | | All work done between the completion of the |
| separate sound floating about among all the others. | | | | hammer's work and the completion of the damper's |
| In the case of the hammer, it was pointed out that its | | | | work is done by the sounding board of the piano; but |
| complete work is finished in the shortest possible time, | | | | as this intermediate work is altogether beyond control |
| that it is finished instantaneously, and that although the | | | | of the finger, it cannot come under any consideration |
| key be kept down (and therefore may be understood | | | | concerning the manner of touching the keys. |
| to be fulfilling some function), still nothing more must be | | | | |