Recording instruments and live electronics

I have written a number of pieces for solo instrument and live electronics over the past decade or so. These have included semi-improvised works, works with hardware electronics, interactive electronics, pieces where the electronics is performed with either a score or instructions. In every case, the electronics and the instrumental sound have been recorded simultaneously, irrespective of whether the recording has been in a concert hall or a recording studio. It has never occurred to me to do otherwise: it is like recording a duet or ensemble - there is a need to capture the interaction.

However, I recently needed to pay a performer an hourly rate to do a session for me, and so to save time I decided to record the piece without the electronics with a view to adding it afterwards. The piece (for Piano and electronics), uses sound as the medium for interaction between the performer and electronics - there is no electronics score, no physical control.

Under normal circumstances, with this type of piece, I wouldn’t consider recording the acoustic instrument separately, but in retrospect it makes some sense. The piece uses what I would call ‘high risk’ techniques in the the electronics, i.e. there is a strong possibility that at times, the electronics will not work as desired. This is fairly common in live electronics works that involve an experimental or ‘research’ component. Recording the instrument separately, and adding the electronics in the studio avoids this, enabling the electronics to be presented as intended, without the small idiosyncrasies that occur in a live performance. The illusion of interaction can be achieved through editing…

It seems that people expect recordings to be perceptually flawless and polished, whilst in live performance they tolerate a degree of error in return for an added element of excitement. This seems reasonable in the context of the majority of performances and recordings, because recordings need to endure repeated listening whereas performances are ephemeral. However, the problem for me is determining what constitutes a flawless recording in the context of live electronics. The more flawless we make the recording, the closer to the composer’s intended sound world, the closer it gets to becoming a piece for instrument and tape.