The following is partly taken from , p. 129:
``Monitoring is the task of controlling and modifying technical and phonetic characteristics on-line, i.e. during the course of a recording. Validation relates to an off-line (or post hoc) technical or phonetic evaluation of the material recorded. Two on-line monitoring paradigms can be distinguished: one in which any deviation or error is signaled to the experimenter only, and another one in which also the speaker is informed that a particular error has occurred. Some characteristics of recorded speech can only be evaluated after the recording has taken place. In the technical domain such characteristics are the signal-to-noise ratio for the whole material, and an analysis of noises that were recorded with the speech.''