The
*Antiphonal groups* fragments are composed of cycles between
polychoral blocks. A singer is still central for every group.

An irregular sawtooth curve with up to 4 full rotations through the room trigger entrances for the 5 singers. Moderate curves create audible spatial paths, while steep curves blur spatial positions into an overall polyphony.

5 vocal rhythms are doubled by ensemble groups. Gesture type and chord structures are used as inputs added to the vocal rhythms in 5 turns.

Woodwinds perform single multiphonic sounds. Oboe multiphonics are well explored by Peter Veale.

^{1}At times the oboe fluctuates between the possible underblown and overblown pitches, creating transparent sounds.The cello is the only musician to perform rapid figurations, slightly out of sync with the rest of the group.

The rest of the ensemble perform notes with variations of dynamics and playing techniques.

Singers
recite freely chosen texts from *Finnegans wake*.^{2}
3 of them through a kazoo, 2 with live
choir harmonization.^{3}
Through 5 *Antiphonal groups* versions, all singers will sing 2
times with harmonization. Notes of the virtual choirs have individual
dynamic levels, and follow independent spatial paths through the
whole room. The two singers with harmonization will thus have a wider
spatial distribution than the rest of the ensemble.

Chords are ad hoc just intonation transpositions from sung pitch. To clarify this non standard approach, we will look at the choir harmonization for all 5 fragments.

**AN
Antiphonal groups 1**

**Stine**

A sung pitch is used as an input.

All the following ratios are multiplied by the frequency of the vocal pitch.

A resulting chord can be approximated to notation. The harmonization
will still use the more precise overtone transpositions. Pitches will
move in parallel with the voices in these fragments.^{4}

**Eva**

A sung pitch.

Ratios multiplying the frequency.

Approximate chord notation.

**CL
Antiphonal groups 2**

**Liv**

A sung pitch.

Ratios start from the sung pitch, the following notes are all calculated from previous note.

Resulting pitches are different from when all pitches are multiplied just from the initial note. Overtone relations can grow more distant.

**Anita**

A sung pitch.

Ratios start from the sung pitch, the following notes are all calculated from previous note.

The approximate chord.

**BZ
Antiphonal groups 3**

**Maria**

A sung pitch.

Ratios start from the sung pitch, the following notes are all calculated from previous note.

The approximate chord.

**Liv**

A sung pitch.

Ratios start from the sung pitch, the following notes are all calculated from previous note.

The approximate chord.

**DC Antiphonal groups 4**

**Stine **

A sung pitch.

Ratios multiplying initial the frequency.

The approximate chord.

**Anita**

A sung pitch.

Ratios multiplying initial the frequency.

The approximate chord.

**CF
Antiphonal groups 5**

**Maria**

A sung pitch.

Ratios multiplying initial the frequency.

The approximate chord.

**Eva**

A sung pitch.

Ratios multiplying initial the frequency.

The approximate chord.

All these harmonizations by overtone ratios can create resonant chords. If transpositions were equal tempered, we would hear notes separately. Fine nuances of intonation can make chords blend into a single homogenous sounds. Sonorities reach vagueness of sound quality as overtone relations grow more distant than for a spectrum over a deep unambiguous fundamental.

'Expansion
of Grains tuning'^{5}
is created through similar just intonation principles, not optimal
for centered tonality. The organist must continuosly explore
unexpected interval qualities through the keyboard range.

While
Tristan Murial has worked within 'frequency based composition',^{6}
Harry Partch created tuning systems suitable for his microtonal
instruments. Fixed tuning systems, and the always unique results of
acoustic analysis and transformations, have different qualities. Ad
hoc tuning systems exist within single fragments, while other systems
are explored in a variety of contexts. I will not make a choice
between ’fixed’ and ’fluid’ intonation systems, rather see
valuable elements for a larger vocabulary.

Example 62: CF Antiphonal groups 5

1 [Multiple_authors] Peter Veale , The Techniques of Oboe Playing.

2 James Joyce, 1992, Finnegans wake.

3 Ircam's psychoirtrist~ object for MaxMsp.

4 It is also possible to define static harmonizer frequencies for psychoirtrist~.

5 Ruben Sverre Gjertsen, 2013, 3 Manual Microtonal Organ, p. 15.

6 Rozalie Hirs, 2009, Contemporary compositional techniques and openmusic, p. 94.