Abstract: Systems and methods are provided for measuring the distortion and muffling caused by a face mask. For example, in one embodiment a simulated voice source produces a sound. The sound is then acoustically coupled to a simulated vocal tract and a face mask. A microphone receives sound and produces a signal and an analyzer receives the signal from the microphone. A manikin head or other facial structure may also simulate fitting of the face mask onto a face. The analyzer may further produce a quantitative assessment of the distortion and muffling of the face mask, for example, by comparing at least one spectrum obtained with the face mask and at least one spectrum obtained without the face mask.

Abstract: An acoustic face mask reduces the distortion and muffling of speech sounds by a face mask wall. The distortion and muffling of speech sounds by a face mask wall may be reduced by reducing the acoustic coupling of the vocal tract and/or nasal cavity to the face mask chamber, which causes a reduction in the intelligibility of the speech. The acoustic coupling of the vocal tract and/or nasal cavity to the face mask chamber may be reduced, for example, by reducing the reflected sound energy caused by the face mask wall. For example, one or more sound absorbing members or acoustically transparent members reduce the reflected sound energy caused by the face mask wall.

Abstract: An acoustic face mask reduces the distortion and muffling of speech sounds by a face mask wall. The distortion and muffling of speech sounds by a face mask wall may be reduced by reducing the acoustic coupling of the vocal tract and/or nasal cavity to the face mask chamber, which causes a reduction in the intelligibility of the speech. The acoustic coupling of the vocal tract and/or nasal cavity to the face mask chamber may be reduced, for example, by reducing the reflected sound energy caused by the face mask wall. For example, one or more sound absorbing members or acoustically transparent members reduce the reflected sound energy caused by the face mask wall.

Abstract: A method and device is described for estimating the subglottal air pressure during speech or singing from the intraoral air pressure in essentially real-time by using a type of peak detection and extrapolation means that holds peaks in the low-pass filtered pressure signal for a period of time sufficient to allow their interpretation as real-time subglottal pressure. An electronic circuit suitable for implementing this function is described.

Abstract: A method is described for correcting and improving the functioning of certain devices for the diagnosis and treatment of speech that dynamically measure the functioning of the velum in the control of nasality during speech. The correction method uses an estimate of the vowel frequency spectrum to greatly reduce the variation of nasalance with the vowel being spoken, so as to result in a corrected value of nasalance that reflects with greater accuracy the degree of velar opening. Correction is also described for reducing the effect on nasalance values of energy from the oral and nasal channels crossing over into the other channel because of imperfect acoustic separation.

Abstract: A system is described for providing biofeedback to hearing-impaired persons as to the degree of nasalization of vowel-like sounds in their speech, in order to monitor their own nasality and thus correct inappropriate nasalization. In a preferred embodiment, this feedback uses tactile vibration, with the vibration frequency or amplitude reflecting the nasalance of the speech.

Abstract: A method is described for correcting and improving the functioning of certain devices for the diagnosis and treatment of speech that dynamically measure the functioning of the velum in the control of nasality during speech. The correction method uses an estimate of the vowel frequency spectrum to greatly reduce the variation of nasalance with the vowel being spoken, so as to result in a corrected value of nasalance that reflects with greater accuracy the degree of velar opening. Correction is also described for reducing the effect on nasalance values of energy from the oral and nasal channels crossing over into the other channel because of imperfect acoustic separation.

Abstract: A system is described for providing biofeedback to hearing-impaired persons as to the degree of nasalization of vowel-like sounds in their speech, in order to monitor their own nasality and thus correct inappropriate nasalization. In a preferred embodiment, this feedback uses tactile vibration, with the vibration amplitude reflecting the nasalance of the speech.

Abstract: A method of and device for the diagnosis and treatment of speech dynamically measures the functioning of the velum in the control of nasality during speech. Various components of oral and nasal airflow are separated and selectively analyzed including (i) the fundamental frequency component of each airflow during voiced speech, (ii) a plurality of voice components that cover a frequency range encompassing at least the lowest vocal tract resonance (the first formant), and (iii) the subsonic and infrasonic components of at least the nasal airflow. By comparing the nasal and oral airflow components at the voice fundamental frequency, a nasalization measure for voiced speech sounds is formed which emulates methods that compare low frequency nasal and oral airflow during voiced speech, while eliminating or greatly reducing the problems associated with comparing these low frequency airflows, and which improves upon previous methods based on measuring and comparing nasal and oral radiated sound pressure.

Abstract: A system and apparatus for teaching prosodic features of speech senses and extracts prosodic or suprasegmental variables of a user's speech segment. Prosodic features of speech include pitch and loudness variations, as opposed to articulatory or sequential features of speech which are the primary determinants of phoneme variations. Once prosodic variables have been extracted from a speech segment, the variables are used to modulate a quasiperiodic waveform such as a sinusoid, a pulse-train, or a synthesized vowel-like waveform, or the parameters can be used to modulate a random-noise-like waveform. A modulated waveform can be played acoustically, and the user can hear the variation of the prosodic parameters without interference from the articulatory parameters of a complete waveform. This auditory feedback can be combined with visual feedback of the speech segment to teach proper prosodic speech formation.

Abstract: A system and apparatus for teaching prosodic features of speech senses and extracts prosodic or suprasegmental variables of a user's speech segment. Prosodic features of speech include pitch and loudness variations, as opposed to articulatory or sequential features of speech which are the primary determinants of phoneme variations. Once prosodic variables have been extracted from a speech segment, the variables are used to modulate a quasiperiodic waveform such as a sinusoid, a pulse-train, or a synthesized vowel-like waveform, or the parameters can be used to modulate a random-noise-like waveform. A modulated waveform can be played acoustically, and the user can hear the variation of the prosodic parameters without interference from the articulatory parameters of a complete waveform. This auditory feedback can be combined with visual feedback of the speech segment to teach proper prosodic speech formation.

Abstract: The invention extends the capability of conventional computer speech recognition programs to reliably recognize and understand large word and phrase vocabularies for teaching written language skills. At each step of a teaching program, information is supplied to the user such that some responses in the language being taught are correct (or appropriate) and some are incorrect (or inappropriate), with these respective sets of responses judiciously selected to teach some language aspect (i.e., vocabulary, sentence structure). A subset of allowable correct; and incorrect responses is selected such that a speech recognition subprogram readily discerns certain allowable responses from other allowable responses, including each incorrect response being discriminable from each correct response. The meanings of at least the correct allowable responses are made clear by aural or visual information, such as graphic images, printed text, or translations into the user's native language.

Abstract: A system and apparatus for teaching prosodic features of speech senses and extracts prosodic or suprasegmental variables of a user's speech segment. Prosodic features of speech include pitch and loudness variations, as opposed to articulatory or sequential features of speech which are the primary determinants of phoneme variations. Once prosodic variables have been extracted from a speech segment, the variables are used to modulate a quasiperiodic waveform such as a sinusoid, a pulse-train, or a synthesized vowel-like waveform, or the parameters can be used to modulate a random-noise-like waveform. A modulated waveform can be played acoustically, and the user can hear the variation of the prosodic parameters without interference from the articulatory parameters of a complete waveform. This auditory feedback can be combined with visual feedback of the speech segment to teach proper prosodic speech formation.

Abstract: The invention extends the capability of conventional computer speech recognition programs to reliably recognize and understand large word and phrase vocabularies for teaching language comprehension and oral production skills. At each step of a teaching program, information is supplied to the user such that some responses in the language being taught are correct (or appropriate) and some are incorrect (or inappropriate), with these respective sets of responses judiciously selected to teach some language aspect. A subset of allowable correct and incorrect responses is selected such that a speech recognition subprogram readily discerns certain allowable responses from other allowable responses, including each incorrect response being discriminable from each correct response. The meanings of at least the correct allowable responses are made clear by aural or visual information, such as graphic images, printed text, or translations into the user's native language.

Abstract: A pneumotachograph mask or mouthpiece coupling element may reduce the distortion and muffling of the voice otherwise caused by a mask or mouthpiece when measuring the low-frequency components of a volume-velocity of oral or nasal airflow during speech or singing. This improved performance is accomplished by separating the low-frequency components to be measured from the higher frequency or acoustic components by an acoustic filter. The filter passes much of the acoustic energy through the walls of the mask or mouthpiece at a location or locations close to the face. The lower frequency airflow components are funneled by the mask or mouthpiece coupling element through an airflow-measurement transducer. The acoustic filtering can be implemented by a membrane, or array of membranes, in the wall of a chamber located close to, or formed as part of, the mask or mouthpiece.

Abstract: A tracking multielectrode electroglottograph has a number of electrodes that are located about each other in opposed arrays placed on either side of a subject's neck during vocalized speech or singing. Each pair of opposed electrodes within the arrays is coupled to a separate channel of the electroglottograph electronics, which, in turn, provides an output signal which reflects, in large measure, the variation with time of the area of contact between the vibrating vocal folds within the subject's larynx. Each channel has a send circuit containing a signal generator that is isolated from the other channels and which produces a high frequency carrier that is synchronized with the carriers from the other channels so as not to produce beats. Each channel also has a receive circuit with input connected to the output of the respective send circuit and to the respective pair of opposed electrodes. The electrodes and the send and receive circuits can be connected either in parallel or in series with each other.

Abstract: A technique for extracting voice parameters from oral or combined oral and nasal air flow involves having a test subject or patient pronounce a vowel sound that has a high first formant into a pneumotachographic device which produces an output voiced speech waveform that includes the mean air flow. This output signal is appropriately filtered to remove the formant frequencies and produce a smoothed glottal waveform approximation. From the pneumotachograph output waveform and smoothed glottal waveform are derived a peak value P, a minimum value L, glottal wave period T.sub.O and average value M for the glottal waveform. The amplitude and wave center value can readily be calculated, and from these the open quotient Q.sub.O can be derived which represents the ratio of the duration of the open portion B of the glottal wave cycle to the entire period T.sub.O thereof.