A few considerations on the music of Messiaen - a fellow synaesthete - that resonate with the Streamland idea.
"The bird's ritournelle (ritornello) not only defends a terrain, it also establishes continuously the terrain by encircling it with song. It is the bird's "song of the earth," linking place and color with sound, weaving together ornamented terrain (patterns of leaves, etc.) with ornamented rhythm. The ritournelle is simultaneously pure expression and a returning "fold" that wards off death and other threats and becomes also a song of courtship."
The relevance of this for Streamland is simply in the aesthetics - I get a sense of this 'ornamented terrain' often when I make music. Patterns of leaves, the light in the spaces between and the colour of bird-songs are recurring inspirations and atmospheres that I sense myself within.
"If one reverses a retrogradable series as follows: 1,2,3,4, 4,3,2,1, then the entire unit of eight elements is itself non-retrogradable, palindromic… these palindromic devices were associated with magical conjuring formulae and Messiaen spoke of a "good magic" that concerns the ability of music to invoke the cosmos in a new way and to evoke and alter human emotion."
This idea of the palindrome relates to the technique in the Streamland instrument of sample reversing - flipping the playspeed of a sample backwards and forwards, effectively mirroring fragments.
Pickstock, C. 2007, “God and Meaning in Music: Messiaen, Deleuze, and the Musico-Theological Critique of Moderism and Postmodernism” in Sacred Music, 134.4, pp40-62