The narrow phonetic level of representation is the first one where the transcriber cannot avoid listening to the recording and/or inspecting the waveform and spectrogram. This is because it attempts to represent what the speaker actually said at the time of recording. This consideration immediately increases the time and effort necessary, as every part of the speech must be inspected manually.
The inventory of symbols is increased to include sounds that do not have
phonemic status in the language (such as a glottal stop
for English, or a symbol
for aspiration after a voiceless plosive). It is at this level that different
allophones may be represented, as well as devoicing or voicing , and secondary
articulations such as nasalisation or labialisation. One segment at this level
(e.g. a voiceless plosive) may correspond to more than one segment on the
acoustic-phonetic level (e.g. the closure phase and burst of a plosive). There
are potential problems in determining the boundaries of segments at this level,
especially in the case of ``desequencing'' or transposition of two sounds (Barry
and Fourcin, op. cit.). However, this level of representation will be far more
accurate as a record of what was said. This implies that not so much data will
be needed, provided it is accurately transcribed at this level.
It is better not to embark without good reason on this level of representation, which requires the researcher to inspect the speech itself, as this greatly increases the resources needed (in terms of time and effort). If the broad phonetic (i.e. phonotypic) level is considered sufficient, then labelling at the narrow phonetic level should not be undertaken.