Stopping, known as stopfen, is employed by many Classical and modern composers. Usually, stopping is accomplished with the hand. But this is not always a simple matter, especially in forte passages or in the low register. “Horns too late!” is an often heard comment from conductors, so producing a precise and direct stopped sound is required, as well as good intonation.
The Powerstopf is the stopping mute that gives the horn player the means he or she needs to stop easily and in tune. The combination of aluminum and oak results in a direct sound that is identical to the tone color of actual hand stopping.