During the second day of Sound of Stockholm, Jacob Kirkegaard will present Eustachia for Voices – a vocal work composed from tones generated in the inner ear. The ears of only few people are constantly producing faint, but constant acoustic tones: spontaneous otoacoustic emissions (SOAE). Each emitting ear produces something akin to an acoustic fingerprint: whereas the combinations of tones emitted from one ear can be dissonant, microtonal and complex, tones emitted from another ear can be harmonious and ‘in tune’.

Eustachia is created from a selection of individuals’ ears that emit these tones. Recorded and amplified by Jacob Kirkegaard, the recorded ‘ear chords’ are filtered, analyzed, and interpreted for voices in the format of a choir. Thus, the work connects two intimate organs of our body: the ear and the throat. Whilst the ears are the composers, the throat and serve as performers of the sound that is heard. In the spring of 2017, Kirkegaard recorded the sound of emitting ears from Aarhus Pigekor, which he later filtered and organized them as chords into a composition.

The Sound of Stockholm version of Eustachia adds a third layer to the work, which is the copying action of a voice that interprets what the ear is hearing. Thus, the choir reenacts the sound of the absent ear which initially emitted the very tone. Together, the choir sings a composition of tones, which the authoring ears still haven’t heard themselves.  

For this occasion, the choir Birdies joins Jacob Kirkegaard. Birdies is comprised of approximately twenty-five members of mixed gender who have worked together over a ten year period. The choir is led by Lina Åberg, who also writes and composes a majority of their arrangements.