Electro-acoustic chamber ensemble Sonic Generator returned to the Woodruff Arts Center’s Rich Theatre stage on Tuesday to perform music by Mario Diaz de Leon, Daniel Wohl, Nathan Davis and Michel van der Aa. The concert was promoted as “Four Under Forty,” because all those composers are under 40 years old. But in the end, that topical title wasn’t really needed to conceptually bind the concert together for the audience; the music itself did that quite well.
The opening work was Mario Diaz de Leon’s “Mansion,” composed in 2009, performed by flutists Jessica Sherwood and Christina Smith and percussionist Thomas Sherwood. A driving percussion part and swirling lines on the amplified alto flutes were set against a dense and mostly raw-edged audio track. At several points in the piece, the pre-recorded audio part abruptly broke into spates of silence as if someone had simply and ungraciously turned off the noise with a switch for a few moments. The end, in which the alto flutes had the most prominent say, was not so abrupt but died away quickly rather than go out in a long fade.
The next three works were all solos. Pianist Tim Whitehead performed Wohl’s “Aorta” (2010), a three-movement set that included an electronic audio track made up of distorted piano sounds. In his notes on the piece, Wohl describes the pre-recorded audio part as being connected to the piano part in different ways for each movement: as complements, as mirror images and as gridlocked to the piano part. But the overall impression — that the electronic and piano were intrinsically tied together as if two parts of one instrument — was more important.
The same impression was true of the last of the three solo works, “Oog” by Dutch composer Michel van der Aa, performed by cellist Brad Ritchie. Written in 1995, “Oog” (“Eye”) was the oldest and the only 20th-century work on the program. Just as Wohl did with piano, van der Aa did with cello in deriving the recorded sounds from the instrument itself and modifying them, with the exception of sounds derived from stones. In addition to long tones, varied staccato articulations and occasional whip-cracking bowing, Ritchie was called upon early on to tap out a persistent mechanical pulse on the body of the amplified cello. Van de Aa, who in addition to being a composer is also noted as a film and stage director, calls upon the element of visual illusion, requiring the cellist to pantomime as if playing against the recorded track.
Between the solos by Whitehead and Ritchie, Tom Sherwood performed “Diving Bell” by Nathan Davis. Davis, himself a percussionist, composed the piece as a controlled improvisation for triangles that are amplified and subjected to live digital audio processing. Sherwood used a hand-held microphone in his left hand like an audio probe, capturing at close proximity an array of timbres and harmonics naturally derived from striking or stroking the triangles at different places with a variety of beaters. The processing of sounds through a laptop computer was controlled by Sherwood with a set of foot pedals, adding a palette of shifting, ghostly swoops to the natural tinkly ringing of the triangles.
The Sherwoods, Ritchie and Whitehead were joined by violinist Helen Hwaya Kim and clarinetist Ted Gurch for the finale, another work by de Leon, titled “Gated Eclipse.” Intertwined with the electronically developed four-track audio, the live instrumental parts were relatively sparse, mostly sustained tones and frequently utilizing extended techniques to achieve less familiar timbral effects. But the overall effect of de Leon’s music was a broad, rich swath of sonic tapestry with plenty of clearly perceptible detail..
It was a consistently strong, aesthetically focused concert that seemed, especially in “Aorta” and “Oog,” to well integrate acoustic and electronic aspects into a feeling of musical singularity. One was left with a sense of ease and assurance with which the Sonic Generator musicians performed these works and with the creative voices of the composers.