Ullmann, one of the most active and inquisitive saxophonists in the German jazz scene and the pianist Hans Lüdemann had both experimented independently with microtonality. The music of mikroPULS lives in the space between the extremes of discovering new worlds and returning to the roots of African-American music. The group's experimentation with microtonality is both an intellectual challenge and a bridge to the music of the African-American experience from which jazz grew and to which all four musicians of mikroPULS feel connected: the blues. Every one of us lives with a tonal system in our head. The diatonic-chromatic-enharmonic system that has long dominated Western music was codified at an early stage through the use of notation. Later, around the beginning of the 17th century, major/minor tonality superseded the old church modes and has influenced our perceptions of harmony ever since. These perceptions are, however, constantly evolving. When blues, jazz and other forms of African-American music brought the first "blue notes" to Europe in the early 20th century, they created quite a stir, because neither their pitch nor their harmonic function fit into the conventional tonal system. Our musical sensibilities are nonetheless learned, not innate. Even if we do not understand music theory, we feel the way the dominant resolves to the tonic; we sense whether chords are more consonant or dissonant. We find our ability to remember melodies that conform to our tonal system self-evident, but are astonished when people form other cultures do the same with their own music.