International Journal of Speech Language and the Law, Vol 22, No 1 (2015)

Impact of mobile phone usage on speech spectral features: some preliminary findings

Slobodan T Jovicic, Nikola Jovanović, Miško Subotić, Đorđe Grozdić
Issued Date: 8 Jul 2015


The manner of using a mobile phone in voice communications can significantly affect the spectral characteristics of the speech signal. This article presents preliminary results of the analysis of the long-term average speech spectrum (LTASS), the long-term formant distribution (LTF) in voiced sounds, and vowel formants F1, F2 and F3 of six speakers in five modes of mobile phone usage. These modes are: normal holding of a mobile phone (NOR), with a bonbon (sweet) in the mouth (BON), with a cigarette between the lips (CIG), with the mobile phone between cheek and shoulder (SHO) and with the hand covering the mobile phone and mouth (HAN). The results show that each mode has an impact on spectral features and that the modes HAN and SHO have the greatest impact. The most striking results are the relative displacement of F1, which can reach 30% (e.g. vowel /a/ in HAN mode for males), formant F2, near 15% (vowel /i/ in SHO mode for males), and formant F3, about 5% (vowel /u/ in CIG mode for females). These findings suggest that forensic practitioners should exercise caution in interpreting formant measurements in speaker identification cases involving mobile phone transmission.

Download Media

PDF (Price: £17.50 ) HTML (Price: £17.50 )

DOI: 10.1558/ijsll.v22i1.17880


Boersma, P. and Weenink, D. (2011) Praat: Doing Phonetics by Computer (Version 5.2.26). Retrieved from

Byrne, C. and Foulkes, P. (2004) The ‘mobile phone effect’ on vowel formants. International Journal of Speech, Language and the Law 11(1): 83–102.

Fant, G. (1970) Acoustic Theory of Speech Production (2nd edn). The Hague: Mouton & Co.

Fecher, N. (2014) Effects of forensically-relevant facial concealment on acoustic and perceptual properties of consonants. Dissertation, Department of Language and Linguistic Science, University of York.

Flanagan, J. L. (1972) Speech Analysis, Synthesis and Perception (2nd edn). New York: Springer-Verlag.

Guillemin, B. J. and Watson, C. (2008) Impact of the GSM mobile phone network on the speech signal: some preliminary findings. International Journal of Speech, Language and the Law 15(2): 193–218.

Ito, T., Takeda, K. and Itakura, F. (2005) Analysis and recognition of whispered speech. Speech Communication 45: 129–152.

Jovičić, S. T. (1998) Formant feature differences between whispered and voiced sustained vowels. AcusticaActa Acustica 84: 739–743.

Jovičić, S. T., Kašić, Z., Đorđević, M. and Rajković, M. (2004) Serbian emotional speech database: design, processing and evaluation. Proceedings of the Conference SPECOM-2004, St Petersburg, Russia: 77–81.

Künzel, H. J. (2001) Beware of the ‘telephone effect’: the influence of telephone transmission on the measurement of formant frequencies. Forensic Linguistics 8(1): 80–99.

Künzel, H. J. (2002) Rejoinder to Francis Nolan’s ‘The “telephone effect” on formants’: a response. Forensic Linguistics 9(1): 83–86.

Lindblom, L. and Sundberg, J. (1971) Acoustical consequences of lip, tongue, jaw, and larynx movement. Journal of the Acoustical Society of America 50(4): 1166–1179.

Nolan, F. (2002) The ‘telephone effect’ on formants: a response. Forensic linguistics 9(1): 74–82.

Nolan, F. and Grigoras, C. (2005) A case for formant analysis in forensic speaker identification. International Journal of Speech Language and the Law 12(2): 143–173.

Rose, P. J. (2002) Forensic Speaker Identification. London: Taylor & Francis.

Shewmaker, M. B., Hapner, E. R., Gilman, M., Klein, A. M. and Johns, M. M. (2010) Analysis of voice change during cellular phone use: a blinded controlled study. Journal of Voice 24(3): 308–313.

Stevens, K. N., and Keyser, S. J. (2010) Quantal theory, enhancement and overlap. Journal of Phonetics 38(1): 10–19.


  • There are currently no refbacks.

Equinox Publishing Ltd - 415 The Workstation 15 Paternoster Row, Sheffield, S1 2BX United Kingdom
Telephone: +44 (0)114 221-0285 - Email:

Privacy Policy