Posthorn
Valveless signal horn of mail coaches.
What it means
The posthorn is a valveless signal horn that was formerly blown on mail coaches. It is usually coiled in a circle or oval and has a narrow tube with a cup mouthpiece. Because it has no valves it can play only the natural tones, that is, above all triad notes and signals. The posthorn announced the arrival of the post and served as a signal.
Musical use
As a symbol of the post it is still known today. Musically it appears as a tone color of distance, for example in Mozart's Posthorn Serenade (K. 320, 1779), in which it sounds in the trio of the minuet, and in the third movement of Gustav Mahler's Third Symphony (1896), where a posthorn solo sounds from afar. In the orchestra it is often replaced by a flugelhorn or trumpet.
The posthorn should be distinguished from the French horn, which is played in the orchestra and has a wider compass, and from the fanfare, which consists of signal figures on several instruments.
Performance practice
When you play the posthorn, keep the tone even and restrict yourself to the clear natural tones. The effect lies in the simple melody and in the soft attack from afar.