VIBRAPHONE THeORIES (2007)
Vibraphone Theories is a set of three rhythmic pieces for vibraphone and sine tones interference beats. The sine tones are played as a stereo electronic music part during a live performance. Microtonal intervals in the sine tone part create amplitude beats, which have been sequenced to create the rhythms notated in the score. When the vibraphone plays notes close in pitch to notes in the sine tone part, additional beating is created. The similar timbres of the vibraphone and sine tones are blended together to sound like one instrument, where the interference beats sound similar to vibrato.
Vibraphone Theories was performed by Kroumata in Sweden for the 2009 International Society of Contemporary Music (ISCM) festival. This piece was also recorded by Portuguese percussionist Nuno Aroso for his CD Technicolor. It has since been performed in New York by Sean Statser in an ExhAust concert titled 'Sine & Syrinx' (2013) and by Daniel Pate in the New York City Electroacoustic Music Festival (2016).
Melatonin is a short experimental excerpt of music created from the colours and design of the painting ‘Melatonin Shift #3’ (from the series Time—Feeling Time 2003–06) by Australian artist Robert Owen. In this sonification of Owen’s painting, it is used as a score that is read from left to right, from top to the bottom of each vertical column. The colour blocks in the painting were analysed as RGB numbers by Amanda’s sister Jayne Blake, which were then mapped to microtonal frequencies. The RGB value of each square or rectangle is used to divide an octave (which contains 1200 cents). The duration of each note in the music composition is set by the length in units of each colour block. A range of synthesised sounds were used to realise this composition. Interference beats can be heard when notes close in pitch or colours close in hue are played at the same time. Some of the columns were layered in the music composition to create a thicker texture. Interference beats can be heard when notes close in pitch or colours close in hue are played at the same time
Glocken Blocken is a rhythmic and energetic percussion solo that combines Marimba and Almglocken (cowbells). Similar phrases are played on the Marimba and cowbells, highlighting the differences in pitch and timbre between the instruments. The cowbells are slightly out of tune, which creates a microtonal variation of the same material played on the marimba.
Glocken Blocken was premiered by percussionist Claire Edwardes at the Sydney Conservatorium in an Ensemble Offspring concert. It has since been recorded by Claire at the ABC recording studios and has been released on her CD 'Kammerbox'.
LOOM PATTERNS (2018)
Looms Patterns is a contemporary piece for portative organ and an electronic music part made from sequenced sine tone interference beats. The piece has a rhythmic grid of 12 pulses per bar, which acts as a loom for the rhythmic and melodic patterns to be woven through. The electronic music part uses the same pitches played in the organ part and extends the limited range of the instrument. The precisely tuned electronic music part contrasts the unstable pitch and tone of the portative organ and at times may create additional interference beats between the live and electronic music parts.
Loom Patterns was premiered at the Art Gallery of NSW by Bree Van Reyk in the 'Music in This Stillness' concert in the Art After Hours concert series. All pieces in the concert were associated with or inspired by the famous French 'Lady and the Unicorn' tapestries displayed at the time at the AGNSW. Loom Patterns was commissioned by the AGNSW.
Node is a flute solo written for Janet Mckay that is a study in using enharmonic fingerings to play specific microtonal pitches that can be found as natural harmonics on the C and G strings of a cello. Each harmonic overtone has an evenly spaced node along a string. When a natural harmonic glissando is played a sequence of natural harmonics are heard. The melodic material in the piece is made from fragments of adjacent linear clusters of natural harmonics that are found on the C and G cello strings. These separate pitch rows or “strings” of frequency values are used as separate motifs that are developed and manipulated to create the two movements of the work.
Intermetallics are compounds that form when certain combinations of two or more metals are mixed together in certain proportions and react to produce a solid phase that is distinctively different from the constituent elements. In Intermetallic, a range of metallic timbres are combined to create new hybrid timbres. Notes close in pitch are heard by the ear as fused tones with various speeds of pulsating interference beats.
This composition has been specifically composed for the Sixxen instruments made by Synergy Percussion for their 2011 performance of Xenakis’ Pleiades. The microtonal notes of the Sixxen instruments are paired with 12 tone equal tempered notes of the vibraphone and crotales to create interference beats. The exploration of interference beats in this piece was influenced by Indonesian Gamelan music and the beating inharmonic partials of a Tibetan bowl being struck.