Clarity is described as a multi-variable scale from clear and consistent to rough or noisy tone. For example, a voice with lots of abduction and FVF constriction is considered low in clarity, whereas a voice that is bright and FVF retracted or neutral is considered high in clarity. This concept overlaps a lot with harmonic to noise ratio.
Harmonic to Noise Ratio (HNR) is the description of essentially how noisy a voice is.
We have harmonics - which are the horizontal lines in the image - and then there’s noise in between, either from constriction, breathiness or a combination. You can see in the image how there is a clean looking pattern on the left, and a noisy one on the right. This can be called the ‘clarity’ of the voice, though it refers specifically to noise and not things like nasality or knodel (tongue root retraction) effects which might also make a voice sound ‘out of place’.
Primary sources of low Harmonic to Noise ratio:
Covers are anything that ‘covers up’ or disguises a part of a voice or acts to modify the overall quality of the voice. An example is nasality.
- tongue root retraction (stitch voice)
- M2 or too low weight