The eight extended chamber works that comprise the late James Tenney’s series of Spectrum Pieces are each based upon a single harmonic series and are rigorously worked out in terms of dynamic “graphing”, timbre, and modulations in pitch. The music mainly proceeds in slow motion, although after a few minutes you might want to change that to “no motion”! Sometimes the instruments appear disconnected from each other, yet subtle collisions occur that result in momentary, gorgeous timbral combinations or shimmering chords.
Among my favorites in the series is Spectrum 3, which mostly resembles a chamber orchestra slowly melting, punctuated by a percussive rejoinder, a lone mallet-instrument plunk, or a soft, dissonant piano chord. Spectrum 5 benefits from more animation than Tenney’s Spectrum “norm” as well as from the bass clarinet’s singular timbre and flexibility. The use of a tape delay system in Spectrum 7 transforms a flute, cello, and piano trio into Charles Ives filtered through Phil Spector’s Wall of Sound.
While no one should attempt to digest all eight Spectrum Pieces in one sitting, or even two in close succession, it’s good to have the whole series together in authoritative, decently but not outstandingly engineered performances for reference purposes.