Given enough curiosity and skill on the part of its player, any instrument can reveal itself as containing sonic multitudes. Part of what made the avant-garde and experimental music of the last century so compelling was the exploitation, by composers and performers alike, of orchestral and other instruments’ potential for producing diverse and sometimes uncanny worlds of sound. Far from having exhausted itself in the creative burst of the postwar period, interest in the sonic potential of acoustic orchestral instruments continues, often with quite exciting results.
Italian trombonist Carlo Mascolo’s My Tubes is an intriguing set of fifteen brief pieces—most running between one and three-and-a-half minutes long—for prepared trombone. All emphasize the physical process of creating sound through a brass instrument with breath, mouth, tongue and voice. For example, Slided takes a single pitch divided by micro-variations and embellishes it with vocalizations mimicking the rhythms of speech, traces of unpitched breath, and durations embodied in quasi-Morse code divisions of time. As its title announces, Mouthpiece emphasizes the role of the trombone’s mouthpiece as it captures and slightly distorts Mascolo’s humming. LFO’s approximates an electronic effect by staging multiple sounds in a kind of out-of-phase,  autocounterpoint. One of Mascolo’s intentions with My Tubes was to make his acoustic instrument sound like a synthesizer or oscillator, and on this piece he does just that.
Like Mascolo, the Norwegian duo of violinist Vilde Sandve Alnaes and double bassist Inga Margrete Aas play a music of timbre that draws extensively on extended technique. And as with My Tubes, Silfr consists of a set of fairly compact individual pieces each of which is centered on a fairly well-defined set of sounds or techniques. The opening track is a rough-edged pulse piece that foregrounds the raw bite and bounce of bowhair on the strings; another pulse-based track, Sprø Glimmer, features the glassy, skidding sounds of sul ponticello bowing. For nearly purely pitchless sound, there is Røykkvarts, whose irregularly rhythmic antiphony is played on the breathy rasp of muted bowed strings. Other pieces work within the close intervals of a semi-tone or less, with very widely spaced pizzicato notes, or build an icy lattice of densely-packed harmonics.
https://www.sofamusic.no/album/silfr
https://www.creativesourcesrec.com/catalog/catalog_409.html
Daniel Barbiero
Avant Music News 