Recently we had the rare opportunity to have an 1860’s Erard in the shop for a brief period. These are exceedingly rare pianos and this one was in fantastic shape. It had been rebuilt and restored to original condition by a very conscientious rebuilder. I was very excited to open the piano and examine the action which dates from very near the invention of the double escapement action built by the inventor of that very action, Mr. Erard. His action design is what all modern grand actions are based upon.
The term “double escapement” refers to the mechanisms ability to “reset” the hammer jack relationship without having to return the key to the fully upright position. You can re-strike a key on a grand piano after returning the key to about the ½ way point. On almost all uprights, and the 1897 Broadwood grand we had in the shop not too long ago, you must allow the key to fully return before it will play again.
The double escapement allows for a much faster repetition and much more subtle soft playing. This is accomplished by a second lever, sometimes called the “balancier” which is attached to a spring. The spring applies a positive lift to the hammer knuckle and when the key is released and the hammer is freed from the back check it is able to lift the hammer, allowing the jack to slide back under the knuckle before the key has fully returned.
There are a few examples of “double escapement” like upright actions. Fandrich & Sons has developed an action with an extra spring connecting the hammer butt and jack which pulls the jack back under the butt, allowing for a quicker repetition. And as the preacher said: “There is nothing new under the sun.” We are just finishing the complete rebuilding of a 1912 Mason & Hamlin upright with a spring designed to push the jack back under the butt also. If you want an upright which plays and feels like a grand… here you are! The Mason & Hamlin will repeat with even less key return than a grand piano. You can get the key to re-strike with the key less than ½ way returned.