Innenraum is a work for alto saxophone, piano, percussion (one udu and one tam-tam), and live electronics that was commissioned by the Swiss ensemble Werktag and premiered in June 2015.
The composition deals with the idea of treating the instruments primarily as acoustic spaces, which are variably connected to one another by means of the live electronics. Each instrument contains both a microphone and a loudspeaker or transducer: A small electret microphone is placed in the neck of the saxophone and a small loudspeaker is placed on its bell. The saxophone can thus both be played conventionally and be used as a filter in a signal chain between speaker and microphone. A transducer is played on the soundboard of the piano and an electret microphone is hung close above the strings. The tam-tam is excited by a transducer placed in the centre of its back and, when playing the tam-tam, the percussionist holds an electret microphone that he or she uses to focus on different areas of the instrument. This is similar to the way the microphone is used in Karlheinz Stockhausen’s seminal work Mikrophonie. Finally, the udu contains a microphone hanging freely inside it and the percussionist holds a small loudspeaker whose distance from the udu’s neck opening alters the feedback. There are thus feedback loops within the interior spaces of the instruments. In the course of the piece, moreover, these loops are extended and different instruments are connected to form new composite spaces.
In Innenraum, sound is not primarily a result of the actions of the performers; rather, it is conceived of as a primary agent that traverses the different instrumental spaces. Since the basic excitation of the instruments is often caused by the feedback or delayed sounds from other instruments, the instruments and the actions of the performers function at times rather as transformations of the existing sound than as its immediate cause. The electronics make heavy use of multiband compression and non-linear distortion techniques, which are also used in Reflexion/Glas.
The piece consists of six large sections, which are characterised by different instrumentations:
A. The piece begins with a 3’30”-long solo saxophone section. At the beginning the mouthpiece is not in the performer’s mouth. After 1’10” the performer takes the mouthpiece in his or her mouth and varies the lip pressure, which changes the acoustic space and therefore the feedback. At 1’28” the performer first starts blowing into the instrument and creates teeth-on-reed sounds and eventually multiphonics. The whole section is a transition from initial outbursts of feedback to steady pitches and finally to a noisy texture that is also diffused over the other instruments.
B. The first part is followed by a 1’35”-long section for solo piano in which the pianist’s actions have the function of altering the electronics by deflecting them in various ways. They function as triggers pushing the electronics into different states.
C. The third section, in which piano and udu play, also has a duration of 1’35”. Both instruments form a common space and the coordinated instrumental actions trigger events and parameter changes. The piano actions are harmonics, scratching the strings, and beating the strings with the flat of the hand. The udu actions are beating the tone hole and subsequent damping of resonances by holding the palm slightly above the tone hole, as well as textural elements consisting of scratching and scraping noises.
D. The fourth section, which has a duration of 1’58”, grows out of the previous section. The udu remains and plays a series of detached gestures and textures that control the articulation of the feedback. They stop, trigger, and alter it. Moreover, the instrumental sounds are recorded and delayed, and towards the end of the section they are diffused over the other instruments, which thereby re-enter.
E. Section five has a duration of 3’20” and is a duo for saxophone and piano. Throughout the section the saxophone’s breath sounds are greatly amplified and played back over the piano; the piano actions are mainly silently held chords that filter the resonances that this causes. The compression controlling the feedback, however, is set up in such a way as to always remain at the border between sounds emerging and dying. There is thus silence in-between outbursts and breath sounds that combine, change in density, and interact in various ways.
F. The final section has a duration of 3’40”. It begins with a solo tam-tam part in which the percussionist moves the microphone according to a described trajectory. After two minutes the saxophone enters and the interior spaces are connected. The saxophone filters what is recorded by the percussionist’s microphone. Finally, the space is further expanded and all three instruments are connected (the only moment in the piece in which this occurs).