Sostenante Pedal

The sostenante pedal is novel sustain pedal for digital pianos developed by George Sioros as a Max for Live device. The pedal selectively controls which MIDI notes are sustained and which are released. The power and novelty of the pedal comes from an intelligent algorithm that releases notes that stand out as dissonant when compared to the harmony formed by the sustained notes. In that way, the pedal adapts to the “overall consonance” of the performance. When the performance is highly consonant, even slightly dissonant notes are released. As the performance becomes less consonant, dissonant notes are more tolerated. At the core of the algorithm lies the Tonal Interval Space (TIS) in which every note or chord is represented by a 12-dimensional vector. In the TIS, the consonance between pitch configurations is relative to their proximity in the space. During a performance, the pedal automatically releases some of the sustained notes or chords based on the relation of their positions in the TIS.

The effect of the sostenante pedal is essentially different form the traditional sustain pedal. For instance, playing loud the notes of a melodic phrase that do not necessarily belong to the harmony of the accompaniment might result in dissonance using the traditional pedal. However, our pedal releases those dissonant notes resulting in a cleaner result while allowing for more expressive performances. The pedal is aimed at professional musicians, prompting them to explore new compositional strategies and musical idioms, as well as amateurs who do not fully master the traditional pedaling techniques.

Below you can find four simple videos examples using the sostenante pedal technique. Examples 2. 3. and 4. depart from three different chords with different levels of consonance (Am, Adim, and {A,D,Eb}, respectively) which regulate the sustain of the proceeding A chromatic scale notes. These three examples highlight the adaption of the pedal to different contexts.

Below you can find two videos of a MIDI rendering of Bach's Sarabande from the Partita No. 1 in B flat major BWV 825 using in the first example a sustain pedal throughout the piece and in the second example the sostenante pedal.