The Boehm system and the Oehler system are different designs for the keywork of the clarinet. They have different fingerings.
The Oehler system is very complicated and because of this it was improved to an easier system, referred to as the Boehm system. The Boehm system is now widely used throughout the world., while the Oehler system is popular among players in Germany and Austria.
Since these two systems have different fingerings, they differ in many design specifications, such as tone hole location, key shape and body bore. As a result, the two types of clarinets sound different. The Boehm system is generally said to deliver a bright and perky sound, while the Oehler system delivers a softer and darker sound.
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