Forty-Nine, Forty-Nine (2011)
for MIDI-controlled Fokker Organ [5:30]

Forty-nine, Forty-nine was written for the Fokker Organ, a microtonal organin 31-tone Equal Temperament, recently restored and installed in the Muziekgebouw aan ‘t IJ in Amsterdam.The title makes reference to the two modes of determining pitches used in the piece—those using the overtone series as a guide (the piece opens with the 7th and 49th partials, beautifully approximated by the Fokker organ, of a low G at around 49 Hz) and the combination of Huygens-Fokker scale steps—49 steps representing a mean-tone 12th, used throughout the piece.

The goal is always to highlight the organ’s unique tuning system with the intervals it best approximates: the just major third, the ‘neutral’ third (9/11), the seventh partial… Later in the piece, arpeggiated ‘spectral’ chords (harmonic series with varying degrees of density and deviation) punctuate a diadic or chordal mid-register melody in an homage to Nancarrow…

The Fokker Organ is also equipped with a MIDI in/out, and can play prepared passages like a player piano or disklavier. Forty-nine, Forty-nine is entirely MIDI-controlled, ‘performed’ by connecting a laptop which plays the MIDI score to the organ.

Forty-nine, Forty-nine was composed entirely in the Maquette environment of OpenMusic, then exported as a MIDI file to be played by the organ.

More detailed information can be found in this IRCAM Forumnet article.

Premiered at the Muziekgebouw aan ‘t IJ in Amsterdam on 27 February 2011.