'Spectral Synaesthesia' is a piece of music written for a string quartet, which was used as part of an art installation exhibited at the Institute of Ophthalmology Art Competition 2006. The composition represents the ongoing interest of the composer to amalgamate science in art and illustrates how music itself can be visually interesting and a work of art in its own right and how most artistic experiences involve a combination of the senses. In particular, this piece deals with the how the senses are disorganized in a group of people who experience synaesthesia (eg some people can see different colours or patterns when they listen to music) and the visual system in humans.

Each light sensitive pigment (opsin) expressed in the human retina is tuned to detect red, green or blue light (within cones) or to measure the intensity of light (within rods). Thus, each protein sequence was converted to a particular note by a simple algorithm generated by the composer and set within a string quartet where each instrumental part represents each human visual pigment: Violin I represents the opsin sensitive to red light (562 nm); violin II represents the opsin sensitive to green light (534 nm); the Viola represents the opsin sensitive to the intensity of light (498 nm), and the Violoncello represents the opsin sensitive to blue light (420 nm)). In all cases, the composer possessed complete control over the rhythm and the dynamics, and some control over the pitch (a range of a major 3rd) of each note.

The piece consists of contrasting sections of dissonance and harmony that utilise different techniques (eg pizzicato, bowing of the string with the wood of the bow etc) typical of string instruments. The change from one section to another is accompanied by a change in time signature and metronome marking (the latter of which represents the wavelength of light absorbed by a particular opsin (eg 56.3 beats per minute is used to symbolise the absorbance of red light at 563 nm)) and is timed to coincide with a change of polypetide domain (eg transmembrane domain) within the tertiary structure of visual pigments when reading from the amino to carboxy termini. The composition begins and ends with an average metronome marking of 50.4 beats per minute, which represents the average wavelength of light absorbed by human opsins. Trills are also included to show all the major tuning sites know to date that are involved in spectral sensitivity.

Overall, this unique piece is filled with scientific information yet this does not distract from some interesting and evocative music.