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The Effects of Percussion on Nearby Horns

A Horn is any family of musical instruments that have been shaped into a conical tube[1], with a narrow end that the musician blows into and a wide end where the sound emerges. Most commonly made of metal, horns have historically been carved out of wood and bone. In more casual settings, the word has been used to refer to any brass instrument and the horn section a mixture of brass and woodwind.

Timpani are percussion instruments. Evolved from military drums, Timpani became staples of a classical orchestra in the 18th Century. They are made of a skinhead stretched over a large bowl.

An ensemble of horn and brass players.


Horns are played by blowing through a mouthpiece attached to the narrow end of a tube. The sound then is amplified by the conical shape and emerges from the wide end. The pitch of the sound produced can be modified in three ways.

  • Lip tension – The most common way to adjust pitch, the horn player chooses to either loosen or tighten their lips. The differing tension in the players’ lips forces the air in the instrument to vibrate at varying frequencies.
  • Valves – Horn players can use any combination of the three valves to change the airflow within the horn, changing the pressure and frequency of vibrations.
  • Changing tubes – While not very common, this method involves manually changing the tubing, often during breaks in a piece. Changing tubes directly changes the length of the instrument, allowing for a large change in pitch.

A type of drum, Timpani are played by striking the head with a specialized timpani mallet or timpani stick. Timpani are tuned by tightenign the skin over the head of the drum.

An example of a timpani

The Effect of Timpani Playing Near Horns

The following effects have been observed when playing a timpani in close proximity to a horn [2] :

  • Change in pitch: Measurements taken in a controlled environment show a slight raise of 20-50 cents (0.2 -0.5 semitones) in the pitch of a horn when a timpani is struck nearby. When being played, a changes of ±20 cents, relative to the tuning of the timpani, have been observed[3].
  • Increase in pressure: Horn players have reported feeling discomfort in their lips after prolonged periods of playing with timpani. When tested in a lab, an observable pressure difference of ~20db was observed[4]. In some cases, horn players have described the sensation as "being hit in the mouth" [5], with several players complaining of injuries after performances.

Application of Findings

The results of the timpani - horn experiment have some use for orchestral arrangements. Horn soloist and composer Douglas Hill recommended "not putting horns in front of percussion" in order to avoid horn players "losing control of pitch" [6].