Obbligati II, Op. 13
by Justin Connolly and Peter Zinovieff

scoring: for flute, clarinet, violin, 'cello and piano with electronic sounds
duration: 9 minutes
composed: 1969


published: no

status: manuscript materials in the Justin Connolly Collection; no tape materials extant. Unavailable for performance.


Pierrot Players, conducted by the composer, 10 Feb 1969 (SPNM sponsored fundraising concert for BSEM.)

Pierrot Players, 30 June 1969


none known

programme note:

The artist Muirhead Bone was making a detailed drawing of a bridge, watched by a little girl. She noticed he was using a ruler, and remarked scornfully, "You can't be a real artist; real artists never use rulers." "I know", the old man replied, "but you won't tell anybody, will you?" The use of technical devices as a direct element in the creative process is still a subject apt to generate more heat than light; but it might be helpful to ignore Bone's example for the moment and to explain briefly how we made use of a computer in our collaboration.

he overall mood of the piece, its duration, the pairing of the instruments, and the programming of the computer were the responsibility of Zinovieff; the interpretation of the data and its realization 1n a score for the player was the work of Connolly; the electronic transformation of the recorded instrumental sound was carried out by both composers in consultation. The problem of making the computer produce numerical data usable in musical contexts was a complex one; the various parameters of sound were dealt with in such a way that the probabilistic operations carried out by the computer could be represented in a graphic form. These operations related to the grouping of events, the kinds of activity required at certain points, detailed articulation of the formal structure, and the placing of elements of contrast and 'surpriseĀ·.

A simple example would be the case where the flute wouLd be required to play a high note in a context where the general pattern of events was becoming louder and higher. This note might be one whose duration was fixed by the computer, or it might be open to some modification by the composer. Connolly's instructions for realisation thus included both specific and general elements; where something was already decided by the computer, the composer's task was to accommodate other, less specific instructions to fit the musical situation.

It is thus a question of the composer reading the information from the graphic score in his own way; the same score would provide fifty composers with fifty different pieces, as indeed would a single fugue subject. The total responsibility of the composer thus remains quite unimpaired by his collaboration with a calculating device. However, without the collaboration the piece would have been significantly different in its details; the assistance of the computer operates at a purely regulatory and disciplinary level.

The overall structure suggest by Zinovieff showed a remarkable likeness to that of a work for large chamber ensemble by Connolly, OBBLIGATI I; the more remarkable his being unaware of its existence, let alone its character, which also concerns itselfwwith contrasts between groups of players. We regarded this as a pleasing example of the operation of chance, and adopted the title for the present work. In OBBLIGATI II, five players are heard, so to speak, in triplicate; the live performers being accompanied by two pre-recorded tracks of their own playing. These tracks are subjected to electronic transformation, but in such a way that their instrumental character is not entirely submerged. Live and recorded sounds act as obligate to one another; the piece is in six short sections and lasts about nine minutes.

(Authorship not yet established)


Stanley Sadie, The Times 1-vii-69

other comments:


Programme note: Pierrot Players Programme 30-vi-69, with thanks to James Gardner

Christopher Dromey, The Pierrot Ensembles: Chronicle and Catalogue, 1912-2012 (London: Plumbago, 2013), p. 146