Sonneta Voice Monitor uses the same robust algorithm as Sonneta for Mac® to measure pitch (fundamental frequency) . This algorithm uses a state-of-the-art "waveform-matching" technique  for high precision combined with proprietary logic to improve performance when measuring disordered voices or in the presence of environmental noise or glottal fry. Pitch can be measured in the range 70–1500 Hz.
The semitone scale's origin is set such that the note A4 (440 Hz) = 58 ST.
See also: Comparing pitch apps
Sound Level Measurement
Sound pressure level (SPL) is averaged over 100 ms segments with 12 kHz sampling. Flat frequency weighting is applied to the microphone signal.
See also: Comparing dB apps
 Sonneta Voice Monitor does not provide the same feature set as Sonneta for Mac.
 Goy, H., Fernandes, D. N., Pichora-Fuller, M. K., van Lieshout, P. (2013). Normative voice data for younger and older adults, Journal of Voice.
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