On the Relationship between Glottal Pulse Shape and Its Spectrum: Correlations of Open Quotient, Pulse Skew and Peak Flow with Source Harmonic Amplitudes

Christer Gobl, Andy Murphy, Irena Yanushevskaya, Ailbhe Ní Chasaide


This paper explores the relationship between the glottal pulse amplitude (Up) and the amplitude of the first harmonic (H1), as well as the combined effects of Up, the open quotient (Oq) and degree of pulse asymmetry/skew (Rk) on the low end of the source spectrum. This serves to elucidate their relationship to the H1-H2 estimate, widely used to make inferences on changes in Oq and voice quality. It has been suggested that H1 is mainly determined by Up and that the pulse shape has a relatively small impact. To investigate this, a series of glottal pulses were generated using the LF model, where Up was kept constant, while Oq and Rk were systematically varied. The resulting harmonic amplitudes of these pulses show that Up is not the sole determinant of H1. Rather, H1 is highly dependent on Oq and to a certain degree also on Rk. Although the effects of these parameters on the lowest harmonics is rather complex, we find that the H1-H2 measure is broadly correlated with Oq. However, there is also a strong effect of differences in glottal skew, particularly at high Oq values, which could invalidate inferences on Oq and voice quality from estimates of H1-H2.


 DOI: 10.21437/Interspeech.2018-2532

Cite as: Gobl, C., Murphy, A., Yanushevskaya, I., Ní Chasaide, A. (2018) On the Relationship between Glottal Pulse Shape and Its Spectrum: Correlations of Open Quotient, Pulse Skew and Peak Flow with Source Harmonic Amplitudes. Proc. Interspeech 2018, 222-226, DOI: 10.21437/Interspeech.2018-2532.


@inproceedings{Gobl2018,
  author={Christer Gobl and Andy Murphy and Irena Yanushevskaya and Ailbhe {Ní Chasaide}},
  title={On the Relationship between Glottal Pulse Shape and Its Spectrum: Correlations of Open Quotient, Pulse Skew and Peak Flow with Source Harmonic Amplitudes},
  year=2018,
  booktitle={Proc. Interspeech 2018},
  pages={222--226},
  doi={10.21437/Interspeech.2018-2532},
  url={http://dx.doi.org/10.21437/Interspeech.2018-2532}
}