Non-unison string course scordatura

Tuning at least 1 of the strings within a dichord or trichord course to another pitch than the other(s), creates a non-unison string course scordatura.
Not only do the pitches change, but the timbre changes as well.
By pressing only one key, one can create beat tones, micro-clusters and, with a more radical detuning, even small chords.
If one applies a similar non-unison string course scordatura to other keys as well, a ‘second instrument’ within the piano can emerge.

Micro-clusters

Tre corde. Middle range.

  1. forte
2. piano
Arpeggio
Chord
One of the strings is raised by a quartertone.  
One of the strings is raised by a quartertone, while another one is raised by an 1/8-tone.
One of the strings is raised by an 1/8-tone, while another one is raised by a 1/16-tone.

Using the una corda pedal in combination with non-unison string courses, opens up to several possibilities, and one may read more about this under the technique ‘Use of the una corda pedal’.

Examples of works including this technique: