Monday, May 30, 2011

How Pianos Work

Have you ever looked at a piano and wondered how it makes a sound? Most of us have played a piano at one time or another (making music or just pressing the keys). Let's look at some facts about pianos:

• Most modern pianos have 88 keys; 36 black keys and 52 white keys.

• Pianos were originally called "pianofortes" because of their abilities to play soft and loud. 

• The first modern piano was made in the early 1700's, by an Italian man named Bartolomeo Cristofori. 

• There are over 10 million pianos in American homes, businesses, and schools.

• Pianos can play 7 octaves, which allows them to be one of the most versatile instruments!

• The moving parts of the piano are called the action, which has about 7500 parts.



But with so many parts, how do pianos manage to make noise? First, we need to know that there are many strings inside the piano that are different lengths and tensions. Depending on the length and tension of the string, there will be a different pitch (sounding note). Kind of like a guitar or violin!

Now what? Let's say you want to play middle C. When you press down on the middle C key, a tiny hammer will strike down on the middle C string. The key acts like a seesaw, but much longer on one end. Pressing down on the middle C key will make the seesaw move, striking the hammer against the middle C string. The hammer is underneath the string. 

When you press down and hold, the hammer will remain on the string and continue making sound. After you release the key, the hammer will move off of the string, allowing the damper, which is on top of the string, to stop the note. Watch the video below. You will hear the hammers striking the strings. The black, moving parts are the dampers which stop the sound. 




Piano gets it name because it can play loudly and softly. When the hammer strikes the string, it creates a vibration. Our ears here these vibrations as sound. To play loudly, you strike the key harder. This will cause the hammer to strike harder, making bigger vibrations (larger sound waves). Pressing lightly on the keys, will do the opposite: making a softer sound. 

Here's a photo the the dampers above or on the strings. You can see that some of the dampers are raised, meaning those strings are being struck by a hammer. The others are sitting against the strings, keeping them from vibrating.



There are more things that go into making a piano sound like it does, but now you know the basics! Next time you play, take a minute to look under the case and see what's going on.