Kinematic and Acoustic Changes to Vowels and Diphthongs in Bite Block Speech

Purpose We examined the effect of bite block insertion (BBI) on lingual movements and formant frequencies in corner vowel and diphthong production in a sentence context. Method Twenty young adults produced the corner vowels (/u/, /ɑ/, /æ/, /i/) and the diphthong /ɑɪ/ in sentence contexts before and after BBI. An electromagnetic articulograph measured the movements of the tongue back, middle, and front. Results There were significant decreases in the acoustic vowel articulation index and vowel space area following BBI. The kinematic vowel articulation index decreased significantly for the back and middle of the tongue but not for the front. There were no significant acoustic changes post-BBI for the diphthong, other than a longer transition duration. Diphthong kinematic changes after BBI included smaller movements for the back and middle of the tongue, but not the front. Conclusions BBI led to a smaller acoustic working space for the corner vowels. The adjustments made by the front of the tongue were sufficient to compensate for the BBI perturbation in the diphthong, resulting in unchanged formant trajectories. The back and middle of the tongue were likely biomechanically restricted in their displacement by the fixation of the jaw, whereas the tongue front showed greater movement flexibility.

Binaural speech-to-noise loudness ratio at the speech reception threshold in vehicles

Traditional methods for predicting the intelligibility of speech in the presence of noise inside a vehicle, such as the Articulation Index (AI), the Speech Intelligibility Index (SII), and the Speech Transmission Index (STI), are not accurate, probably because they do not take binaural listening into account; the signals reaching the two ears can differ markedly depending on the positions of the talker and listener. We propose a new method for predicting the intelligibility of speech in a vehicle, based on the ratio of the binaural loudness of the speech to the binaural loudness of the noise, each calculated using the method specified in ISO 532-2 (2017). The method was found to give accurate predictions of the speech reception threshold (SRT) measured under a variety of conditions and for different positions of the talker and listener in a car. The typical error in the predicted SRT was 1.3 dB, which is markedly smaller than estimated using the SII and STI (2.0 dB and 2.1 dB, respectively).

INTELLIGIBILITY OF THE KAZAKH SPEECH WHEN IT'S PROTECTED WITH COMBINED MASKING SIGNALS

The article is devoted to assessing the intelligibility of the Kazakh speech when it's masked by combined signals, including «white» noise and speech-like signals. The phonetics features of the Kazakh language have been considered taking into account the law of syngarmonism and the spectrum differences of speech in the Kazakh language and speech in the Russian language. A technique for assessing the intelligibility of the Kazakh speech when it's masked by «white» noise and speech-like signals is proposed. The aim of the work is to analyze well-known methods for speech intelligibility assessing and applying these methods to assess speech intelligibility in the Kazakh language, taking into account masking by its combined signals. Due to the fact that the use of the articulation method of assessing intelligibility for the Kazakh speech requires a dependence of intelligibility on the articulation index for this particular language (the application for the Kazakh language has not been experimentally tested), the use of the formant approach to speech intelligibility assessing will be examined in more detail. The curried out experimental studies of the spectral density of speech in the Kazakh language made it possible to obtain it's approximate dependence on the frequency and take into account the phonetic features of the Kazakh speech when assessing the security of the speech information using the formant method.

The syllable intelligibility in the system of information transmission by speech signals depending on the intensity of acoustic noise

The paper investigates the effect of the signal-to-noise ratio on syllable intelligibility under the intense influence of external acoustic interference when exchanging voice messages in telecommunication systems of public address systems. The article discusses the effect on the syllable intelligibility of the signal / external acoustic noise ratio, examines the effect of the integral articulation index, the dependence of the perception coefficient of formants on the relative level of formant intensity, the dependence of the formant parameter on the geometric mean frequency of the i-th spectrum of the speech signal. In accordance with the results of studies of the integral articulation index depending on the signal-to-noise ratio, a function of syllable intelligibility depending on the signal-to-noise ratio was obtained, using which it is possible to determine the maximum value of the output signal-to-noise ratio in the audio exchange telecommunications system to obtain a given syllable intelligibility. At the same time, experimentally determined the value of the signal-to-noise ratio in the telecommunications system of audio exchange to obtain a syllable intelligibility of at least 93% for ensure full perception of the transmitted speech information.

CHARACTERISTIC OF SPEECH OF CHILDREN AGED 6-7 YEARS WITH AUTISM SPECTRUM DISORDERS AND DOWN SYNDROME

In this work, the data on the features of speech development in children with autism spectrum disorders (ASD) and with Down syndrome (DS) are presented. Methods of perceptual experiment and instrumental analysis were used. It is shown that in typically developing (TD) children the values of vowel articulation index of stressed vowels in words are maximal in comparison with the corresponding characteristic in children with ASD and children with DS. The words of children with ASD are characterized by high pitch values of words and stressed vowels as well as high values of vowel articulation index. The words of children with DS, besides high pitch values of words and stressed vowels noticed for children with ASD, had maximum duration of words and stressed vowels, low values of the vowel articulation index of stressed vowels. In children with DS, more types of consonant phonemes were not formed compared to children with ASD and TD ones; in addition, children with DS used consonants that do not exist in the Russian language.