Around a Spectral Round
for multi-channel sound // duration: variable, for 1x2: 4'11"
stereo mix, duration (1x2): 4'11"
This piece is actually a collection of pieces, for which different versions can be realized according to different harmonic series contraction parameters. The main gist of it is to construct a spectral mensuration canon (after Tenney [after Nancarrow]), where progressively contracted harmonic sets are played in sequence, according to a temporal offset that is calculated to ensure simultaneous arrival at each set's last remaining pitch at the end of the piece. Some large initial harmonic set is contracted iteratively by mapping the frequency of one of the partials in the curret set onto the highest partial of a new set, and then decrementing the number of partials that comprise the new set by some factor. This process can be manipulated by varying the partial-number offset (how many partials away from the current highest partial will become the frequency of new highest partial), and by varying the contraction parameter (how many less partials will comprise the new set?). Any number of (integer) values for these two parameters can be explored, within some threshold of hearing in order to realize a unique version of the piece. The version that can be heard here is 1 by 2; that is, the frequency of the 87th partial of a set containing 88 partials, becomes the highest frequency in a new set comprised of 86 partials. Each set is then played according to the order of partials (stepping up the series) and in retrograde (stepping down the series). Partials are then played against each other as simultaneities, such that the 88th partial is paired with the first, the 87th with the second, and so on.