Optical computer music system - translates light changes to the series of computer codes, controlling the way the computer music sequences are performed. LTTS (Light Time Triggering System) was designed on Yamaha CX5M computer, later developed on Atari ST computer.

LTTS system was used in following compositions:

WYSYG (What You See You Get) (1989)
for light and computer

BEAUTY AND THE BEAST(1991)
for voice, light and computer

SHA BA DEL'MANA (1994)
ballet

DOUBLES (1994)
for voices, instruments and computer

RIVER DART (1995)
for voices, strings and computer

WYSYG is a new form of audio-visual performance art based on a unique "light conducting" system. Changes in lighting, achieved by the movement of a hand-held lamp, are measured by a set of light sensitive resistors attached to the head of the performer. Each controls a different musical parameter of a pre-programmed score, which resides in the computer. The behavior of the system is as follows:

- the relative duration of simple and complex sound structures corresponds to the frequency that the mouth is opened
- the "orchestration" and sound transformation corresponds to the quantity of light directed at a sensor fastened to the neck

- the localization and spatialization of the sounds corresponds to the quantity of light directed at the ears

In WYSYG there are two abstract energies - light and sound. Light figures are translated into musical phrases. Literary, what you see you get.

Doubles for light, voices and computer was composed in 1994. There are pairs of many elements which works on opposite polarities:

- Material: known material - voices, instruments and unknown material - synthetic sounds and structures

- Style: folk and romantic against atonal and abstract

The most simple relations are the basic idea of the piece. There are many interactive systems used in this piece: light baton, face interface, voice processing, AudioTimeTriggeringSystem etc.

River Dart is the last poem by the Austrian poetess Ingeborg Teuffenbach (1914-1992), which she wrote in May 1992 for her son, Fritjof Capra, a physicist and professor at California's Berkeley University, and well-known in Poland as an author of popular science books. The composition River Dart, for voices and computer was commissioned in 1995 by the Avantgarde Verein from Schwaz, and premiered by Olga Szwajger and Marek Choloniewski at the opening of the 3. Internationale Akademie für Neue Komposition in Schwaz in the Tyrol on 31st August 1995.
The composition, inspired by I. Teuffenbach's poem, is written in the "ambient" convention. The musical layering draws on Fritjof Capra's holistic philosophy, and in particular on some elements of it contained in his two publications Tao of Physics and The Turning Point. It uses several original resolutions which are fundamental to the form of the whole work:

- microtonal harmonies (achieved by the superimposition of the fourth-tone scale on a glissando structure)

- it is performed on an ATTS system (constructed by M. Choloniewski in 1989): tapping batons (chopsticks) at specific points on the graphic score generates consecutive fragments of music stored in the computer's memory.

- the majority of these structures have a temporarily continuous nature and while fading in and out are transformed "live" by the continuous movement of the baton on the music stand where the score is; this movement is transformed by an interactive optical system into glissando cycles the length of the original sound structures.

- the text of the poem, recited in a whisper inaudible but visible to the audience is subjected to a sound delay transformation and transposition and is then mixed with a computer layer of sound; in this way the text becomes audible only after a certain length of time, and in a slightly altered form.

Space and metaphysics are two elements fundamental to the completed form of this piece. This composition also exists in a version with an added group of strings led by a conductor whose reactions to the taps of the chopsticks are slightly delayed. The result of this distortion is a natural delay between the computer instruments and the strings (the computer instruments react immediately to the baton taps, whereas the strings receive somewhat delayed signals from the conductor). The de-synchronization of the two groups of instruments is a conscious manipulation of the composition. This effect is similar to the process of voice transformation, both visually and with regard to the sound production. (WhatYouSeeIsNotAlwaysWhatYouGet) - WYSINAWYG (!?!)