A formant frequency modification algorithm dealing with the pole interaction

Hideyuki Mizuno, Masanobu Abe

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


When a formant is modified based on the pole of the AR model, a problem arises due to the interaction between the pole to be modified and other poles such as the apparent elimination of the formant, if the frequency of the considered pole simply is modified. To solve this problem, the method proposed in this paper uses the spectral intensity at the pole frequency as a new feature parameter and the spectral intensity at the pole after the frequency modification is corrected to the desired value by iterative processings. To examine the effectiveness of the proposed method, an experiment was conducted in which a phoneme in a word is replaced into the same phoneme in a different environment, and then the formant frequency is modified by the proposed method in order to restore the original speech. The speeches before and after the modification are compared in terms of the cepstral distance (CD) from the original speech, and it is verified that the proposed method is effective in the modification of the formant. An attempt is made to solve the formant discontinuity problem at the concatenation point in waveform based speech synthesis-by-rule and to modify the formant frequency accompanying the modification of the fundamental frequency using the proposed method. It was verified as a result of experiment that the speech after formant modification is better than the speech before modification, indicating that the proposed method is useful in improving the quality of the synthesized speech.

Original languageEnglish
Pages (from-to)46-55
Number of pages10
JournalElectronics and Communications in Japan, Part III: Fundamental Electronic Science (English translation of Denshi Tsushin Gakkai Ronbunshi)
Issue number1
Publication statusPublished - Jan 1996
Externally publishedYes


  • Formant frequency
  • Fundamental frequency
  • Spectral intensity
  • Speech synthesis

ASJC Scopus subject areas

  • Electrical and Electronic Engineering


Dive into the research topics of 'A formant frequency modification algorithm dealing with the pole interaction'. Together they form a unique fingerprint.

Cite this