Average/anchor frequency is a term used at our practice to designate the pitch (and by extension, fundamental frequency) that an individual is using during spontaneous, running speech, as determined via auditory perception. We use both “average” and “anchor” together, because some persons speak in a perceptually monotone voice, at which point we consider the pitch extracted via auditory perception to be virtually synonymous with “average” fundamental frequency (proven to be the case in informal study comparing Fo extracted by auditory perception vs. by machine measures).
Other individuals speak with a great deal of pitch inflection. In these cases, we listen for the lowest common pitch to which the voice seems to be “anchored.” When highly inflected speakers become generally fatigued or “depressed,” they tend to default to this pitch, which then becomes more of an “average” pitch for them. Of course, using machine measures of fundamental frequency (primarily using equipment for acoustic analysis), a formal average fundamental frequency can be determined. The ability to determine average/anchor pitch via auditory perception during the vocal capability battery can be learned by clinicians with good pitch perception.