SQA – Fluctuation Strength

Sound Quality Analyzer conducts Fluctuation Strength Analysis on audio WAV files.

Fluctuation Strength (vacil) – A measure of the low frequency (<20Hz) modulation within a signal.  When modulations are less than 20 Hz, the human ear can perceive the individual modulations as single events.  The ear is most sensitive to these modulations at a frequency of around 4 Hz, so the sensitivity of the metric peaks at this modulation frequency.  Values for Fluctuation Strength are typically less than 1 vacil and may be expressed in centivacils. Fluctuation Strength is not a standardized metric.  The SQA uses the Höldrich method of determination of Fluctuation Strength.


Sound Quality analysis - Fluctuation Strength
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