In works which involve prerecorded sound to be played concurrently with live orchestral instruments or voices, the conductor has to identify the sounds on the tape in the course of rehearsal and performance. Some scores provide basic graphics which symbolise the tape part while others simply identify numbered cues for each tape entry. In either case it is imperative that the prerecorded tape be learned thoroughly by the conductor. Only with this preparation can the co-ordination of prerecorded tape and live instruments be achieved. This process is represented in several scores by Jonathan Harvey. His Inner Light 1 demonstrates a remarkable sensitivity and imaginative blending of both elements. The composer has included a graphic representation of the prerecorded tape which includes specific cues for the conductor to identify.

When the notation for the instruments is free or spatial, as in Example 33, an aspect of learning the tape part relates to determining the events as they are introduced by counting in seconds. In marking up my own score as it appears in Example 33, at the bottom of the page I have specified the duration in seconds between each cue on the tape. Above this, in brackets, I have marked the instrumental cues (also in seconds) in a secondary system for signalling the instrumental entries. This is a safeguard which accommodates the very quiet entry of each sound on the tape. It is essential that each tape entry should complement the live instrument. Simply learning the tape sounds without a breakdown in seconds can create poor co-ordination.

As in many such works the tape does not function in instrumental episodes. The electronics performer will stop running the tape and restart at a subsequent section. It is very important that the conductor cues each new entry for the electronics performer with a left-hand signal. Raising the left hand high at least two bars before the cue provides an assured re-entry of the tape. As each entry has a track number, it is not a problem for the electronics musician to start at any point in rehearsal if a bar number is specified by the conductor.