Signals Intelligence has a double meaning. Signals intelligence is the surveillance and collection of electronic transmissions, and now constitutes the largest component of the American security apparatus. It is ominous and omnivorous. In the search for extra terrestrial life, we scan the heavens in search of a transmission from a distant planet. Were we to ever receive such a transmission, it would signal the presence of intelligence by being ordered—non-random—and yet we would have no way to determine it’s meaning. We would be able to only listen, and wonder.

Signals Intelligence explores the experience of hearing an electronic transmission in which order is clearly audible but the information density is too high for any human to parse. The experience is one of being made aware of that which is always just out of reach, just beyond comprehension. Two related algorithms are employed to generate melodic material using from one to six pitches. One algorithm generates a self-similar series which replicates itself when played at different speeds, in effect comprising a mensuration canon in compound melody. The second algorithm generates a self-similar series which is also non-retrogradable (identical when played in reverse order). In the solo version, the results are applied to six indefinitely pitched objects, while in the ensemble version these are mapped to shifting pitch sets and presented in combination with indefinitely pitched instruments.

The ensemble version of Signals Intelligence was commissioned by the Duke University Department of Music for the Milestones 2002 Festival. The "virtuoso" solo version which combines the solo version with part 6 from the ensemble version was proposed by Kyle Forsthoff.

The ensemble version of Signals Intelligence has been released on the CD Epilogue for a Dark Day (Tzadik, 2004) and the solo version on Ecstatic Volutions in a Neon Haze (Innova, 2008)

Ensemble version performed by:
Williams College Percussion Ensemble, dir. Matthew Gold
University of North Texas Percussion Ensemble, dir. Christopher Deane
nief-norf Summer Festival ensemble, dir. Mike Truesdell and Omar Carmenates
Cerebus Percussion Trio + guests
Ensemble 64.8, dir. Morris Palter
McGill University Percussion Ensemble, dir. Aiyun Huang
University of Kentucky Percussion Ensemble, dir. James Campbell
red fish blue fish, dir. Steven Schick
Eastman School of Music Percussion Ensemble, dir. Michael Burritt
Tennessee Tech University Percussion Ensemble, dir. Eric Willie
University of Tennessee Percussion Ensemble, dir. Andrew Bliss
University of North Carolina Percussion Ensemble, dir. Lynn Glassock (premiere)

Discussions about the ensemble version in the Interpreter's Forum

Solo version performed by:
Seorim Lee
Eric Retterer
Alex Lipowski
Robert Dillon
Pedro Carneiro (premiere)

Virtuoso solo version performed by:
Kyle Forsthoff
Eric Retterer
Sean Dowgray

CORRECTIONS TO SOLO VERSION

Close scrutiny of the solo version has revealed a few mistakes. Some scores may still have these errors, so please check your copy. Numbering the objects "1" through "6" from lowest to highest:

m. 32, beat 3, 3rd 16th: should be "1"
m. 35, beat 1, 4th 16th: should be "1"
m. 36, beat 3, 4th 16th: should be "1"
m. 61, beat 3, 2nd 16th: should be "4"
m. 73, beat 1, 4th 16th: should be "6" (thanks to Tom Johnson for finding this one)
m. 82, beat 4, 2nd 16th: should be "1" (thanks to Kyle Forsthoff for finding this one)
m. 104, beat 3, 2nd 16th: should be "4"

CORRECTION TO ENSEMBLE VERSION PARTS

In 2011, a discrepancy between the score and parts was identified by Mike Truesdell. m. 176 of part 5, on page 6 of the part, was incorrectly transcribed. The score is correct. Anyone who has purchased the parts or performed the work may request a corrected page.