Quarter tones The last decades it has become more common to use intervals smaller than a semitone in contemporary music. Quarter tones is the most frequently used micro-tone, and appears in different musical settings, also for brass instruments. Playing quarter tones accurately is a challenge for most musicians, both technically and musically. For brass players (except trombones) the normal method for playing a note in between two semitones, is to “bend” the semitones. This usually have a tendency to affect the sound of the instrument negatively, especially in the higher register. On the euphonium there are several strategies for playing quarter tones, depending on register, musical surroundings, and tempo.
For rapid passages it is useful to find alternate fingering combinations that enables approximate quarter tones. From the middle register on the euphonium it normally is possible to find fingering combinations that brings forth fairly correct intonated quarter tones.
Today it is common to produce euphoniums with a trigger on the main tuning tube, and though this trigger is not originally meant to help playing microtones, it can be helpful in some cases.
The Melton factory has constructed an instrument for the Wikiphonum project especially built in order to handle microtonality and quarter tones. The instrument has five rotary valves in a row with no compencatory system. In addition it has a very fast and flexible trigger on the main tuning tube. The fifth rotary valve lengthens the instrument with three quarters of a tone.
Microtonal music can be defined as all music that contains intervals that are smaller than the conventional semitones of western music. The term includes most forms of tuning/colouring of tones that deviate from equal tempered tuning. Many forms of folk music uses non equal tempered tuning. In this document mainly describes the microtonal phenomenon quarter tones.