Training instrument and method for increasing the carrying power of the human voice as well as for training support when playing wind instruments

Abstract

A method or device that transmits vibrations in the audible frequency range via a shaker to the subglottal region, i.e., the air space between the vocal cords and the trachea. This control allows for precise adjustment of the subglottal frequencies, which influence the vocal characteristics or tonal expression of a wind instrument player.

Description

[0001] The voice is an essential tool for human communication. When vocal disorders are present, those affected are limited in their social functioning. Various exercises can be used to improve voice function, such as relaxing the muscles involved in voice production or practicing breathing exercises. Particularly in professions that rely heavily on speaking, such as teaching, the prevalence of voice problems is reported to be as high as 30%. This can lead to extended absences from work or even early retirement. Furthermore, a strong voice supports efficiency in teaching and interpersonal communication. Targeted vocal training, including training for playing wind instruments by engaging the subglottal muscles, requires both qualified professionals and extended practice.

[0002] Crucially, the airflow through the glottis, the so-called glottal flow, excites the air column in the vocal tract. The shape of this air pulse can contain frequency components of subglottal resonances (Inverse Vocal Tract Adjustment: Spectral Dependence and MRI Data 2020; Hoyer et al. 2022).

[0003] Playing musical instruments is also an important form of interpersonal interaction. Wind instruments are particularly similar to the human voice. In this case, the glottis, as described above, is located at the mouthpiece, either through a tube, a reed, or through vibrating lips or a specific air distribution. Here, too, vibrations are directed from the mouthpiece towards the wind instrument, but are also supported by the vocal tract and the subglottal space.

[0004] The technical challenge in both cases lies in the inaccessibility of the tube system. Teachers usually compensate by inducing mental images and concepts.

[0005] The areas of application therefore relate to the field of medical technology, particularly phoniatrics and speech therapy. Support for patient rehabilitation is also conceivable, as is the treatment of voice problems in professional speakers, the therapy of voice disorders, and music lessons, especially for singers and wind instrument players.

[0006] State of the art: Measurements of acoustically induced vibrations are generally performed outside the body, either using microphones or pressure sensors on the skin. Measurements of voice-induced vibrations, for example in the facial area, are also known (Chen et al. 2014). In other studies, a shaker was used at the larynx (PHAM THl NGOC and BADIN 1994). Excitation of vocal tract vibrations by a shaker attached to the mouth has been used to analyze vocal tract resonances. Loudspeakers or buzzers can be used for this purpose, either emitting a broadband signal or generating a sine sweep. Measurement can be performed by exciting the vocal tract from the mouth (Dickens et al. 2007).

[0007] Subglottal resonances have been known for some time (Fant G. and Ishizaka et al. 1972). Subglottal resonances have been considered as a possible source of vocal resonances. The activation of subglottal resonances in conjunction with vocal tract resonances originating from the mouth has been analyzed (Noel Hanna, John Smith and Joe Wolfe 2018; Hoyer et al. 2022), and their use in voice training has been secured through patents (DE 10 2017 000 570 B3 2018.07.05 and DE 10 2018 000 554 A1 2018.09.13).

[0008] Supportive devices such as "Acapella Choice" are used to send impulses into the oral cavity, reaching the sublottal region. The positive effects of this training device on voice production are currently being investigated (Andrade et al. 2022). Additionally, tubes are used in so-called tube phonation, i.e., voice production by stirring the tube, either with its opening in a container of water or in the open air, to strengthen the vocal muscles and adapt the vibration of the vocal folds to the tubular system (Lax Vox).

[0009] Low-frequency vibrations up to approximately 50 Hz, introduced through the mouth, are used to measure lung properties (Forced Oscillation technique).

[0010] Electrical impedance tomography can provide information about changes in lung volume and vital parameters by measuring measurements around the chest. Discussion of the state of the art and the problem of the invention

[0011] To date, vocal tract and subglottal resonances have been stimulated from the mouth or by the vibrating vocal cords during phonation, or by an external vibration mechanism such as a kazoo, a brass instrument, or a vibrating tube as in clarinets. The stimulation of subglottal resonances from within the body to improve vocal tone or the sound of wind instruments has not been described.

[0012] The invention is based on the discovery that the integration of vocal fold vibrations, or the sound production of wind instruments, into resonant systems can also be achieved from the chest area. Through resonant coupling, the vibration is easier and more sustained. A device for amplifying subglottal resonances for voice training or to support learning success in singing or playing wind instruments has not been described previously. The use of other devices for amplifying subglottal frequencies for voice training is also unknown.

[0013] Training to sustainably improve vocal qualities or to adjust resonance for playing wind instruments typically takes months to years and requires continuous support from specialists (speech therapists, phoniatricians, music teachers, etc.). The connection between vocal function and the subglottal space is strengthened. The perception of a continuous flow through the vocal cords or mouthpiece can be accelerated through training with the device or method.

[0014] A further advantage arises from the connection of the device or the method with the patent applications DE 10 2017 000 570 B3 2018.07.05 and DE 10 2018 000 554 A1 2018.09.13. The combination of adjusting vocal tract resonances and the support provided by the subglottal space represents a particularly effective method in phoniatrics, voice training, and support for playing wind instruments. Description of the invention

[0015] The resonances of the subglottal region are broadbandly activated by a shaker / exciter / body shaker / body sound transducer, or by mechanical surface excitation (hereinafter referred to as a shaker) via the skin to the tubular system consisting of the bronchi, trachea, and vocal tract. Shakers are actively vibrating elements that are applied to a surface, thus setting, for example, a tabletop into vibration, so that they act as loudspeakers. They are also attached to seats in cinemas to enable a holistic cinematic experience through low-frequency acoustic vibrations and their perception in the body.

[0016] The shaker is positioned so that it can excite the air column in the subglottal region. This can be achieved, for example, by fixing it to the sternum. Optionally, the shaker's outward radiation can be reduced by acoustic insulation, thus allowing the effect to be particularly pronounced solely through the vibration of the vocal cords or the musical instrument.

[0017] Excitation is achieved, for example, via deterministic noise, where different frequencies are excited. There are two basic approaches. In one application, broadband excitation is used, so that any resonant frequency of the subglottal space can be excited, regardless of whether the glottis is open or closed. The amplification and attenuation then occur primarily via the resonances of the excited space. In the other case, the subglottal frequencies can first be determined, or the excitations can be set to the subglottal resonant frequencies, or the resonant frequencies of the entire air column when the glottis is open, using a standard set of frequencies.

[0018] The excitation waveform can take various forms. For example, sine tones can be applied at specific subglottal frequencies. Deterministic noise allows for broadband excitation. It is advantageous to align the phase of the excitation frequencies with each other to the subglottal resonances. Stochastic noise can also be used as the excitation signal. In all cases, specific frequency ranges can be emphasized for excitation. For instance, if the higher resonance ranges are to be primarily activated, boosting the excitation signal in the range above 1 kHz to 6 kHz is beneficial. This boost can be based on the position of the subglottal resonances, tuned to vocal tract resonances, or applied linearly.

[0019] The shaker should ideally be positioned so that it effectively stimulates the trachea through the tissue. This can be achieved below the larynx, but also by attaching it to the rib cage or by making contact with the skin at relevant points within the tracheal and bronchial drainage area. These areas include, for example, the rib cage, the sternum, or below the rib cage.

[0020] Recording with this surface microphone during phonation allows for the determination of subglottal resonance frequencies, for example, by analyzing the intensity of individual harmonics or by measuring the gain of different frequency ranges during a sung glissando. Using the tube model, the location of higher-frequency resonances can be estimated. This aspect can also be applied to the inventive aid for playing wind instruments. Example of implementation

[0021] An example of how to improve voice quality is in Fig.Figure 1 shows how the shaker stimulates subglottal resonances. The air column vibrates according to its natural frequencies, meaning that areas where resonances occur are amplified, while vibrations in frequency ranges where anti-resonances are present are disproportionately dampened. These resonant vibrations can further stimulate the vocal tract via glottal flow or by influencing vocal fold vibrations. Adjusting the larynx / vocal folds and vocal tract, including the subglottal space and respiratory muscles, allows for continuous vibration of the entire air column with an audible result. This is usually perceptible to users and improves vocal efficiency. It facilitates energy flow through the vocal folds and reduces vocal fold strain.Through appropriate sensitization and training, the vocal cords can vibrate more freely, less force is used for voice production, and the sound of the voice becomes more pleasant.

[0022] The user trains to amplify frequencies from the subglottal space or to increase the permeability of the vocal cords to these frequencies during phonation. Specific resonance frequencies of the subglottal space can also be targeted for this purpose.

[0023] The shaker's frequency range is advantageously above 200 Hz. Excitation is particularly effective in the frequency range of the so-called singer's formant, i.e., from approximately 2.5 Hz to 3.5 kHz. However, energy bands above this range can also be supported by subglottal resonances, which influence the vibrational properties of the vocal folds and / or the shape of the air pulses used to stimulate vocal tract resonances.

[0024] The intensity of the stimulation can be varied. Training can be adjusted from more support through stimulated subglottal resonances to less stimulation, with stepless adjustments possible. Alternatively, specific intensity levels can be pre-selected to support the training. For this purpose, data from the literature on subglottal resonances can be used, or the subglottal resonances can be individually determined – for example, using a surface microphone below the larynx (e.g., in the pharyngeal notch).

[0025] Furthermore, the use of the device or the procedure significantly reduces the so-called pressing of the vocal cords, one of the most common voice disorders.

[0026] A microphone can document the success of the training and allows a comparison of the voice or the sound of musical instruments before, during and after the application.

[0027] The shaker is electronically controlled and can deliver various frequencies, stimulation functions, and intensities, including individually adjustable ones. It can be equipped with a display that visualizes menu navigation and training sequences, or allows for textual instructions. The device may also feature a speaker that provides audible feedback or instructions.

[0028] The shaker is attached to the skin or thin clothing via a flexible device. With thicker layers of clothing, the coupling of higher frequencies above 1000 Hz should still be possible; that is, the attenuation through the fabric to the skin should ideally be less than 30 dB at 1000 Hz.

[0029] A training procedure can follow the following sequence: 1) Attaching the device in coupling to the subglottal space, e.g. via the sternum. 2) Speaking the text, vocal warm-ups, vocal exercises, recording the voice sound 3) Switch on the device and select an exercise program including predefined frequencies and intensities. 4) Various speech signals are introduced for repetition. 5) The test subject / patient attempts to imitate the language or vocal instructions. 6) The microphone records the vocal signals. 7) The program records the frequency position of the sublottal resonances from the change in the voice signal when subjected to broadband excitation by the shaker. 8) An evaluation of the acoustic result indicates settings where coupling with the subglottal space is detectable. This feedback is given to the user. 9) Specific control of individual subglottal resonances can be selected via the control program. These can be introduced individually or in combination in groups via the buzzer. Frequency ranges / bands can be saved for repeated use. 10) After switching off the shaker, the recordings from step 2) can be repeated. The software compares both recordings. The training effect is evaluated and documented. Feedback to a voice coach can also be provided online after approval and implementation of appropriate IT security features. The before / after recordings can be played back sequentially, or analyses such as the Hammarberg Index or other electronically recorded voice parameters (e.g., the ratio of harmonics in the vocal timbre) can be accessed. Bibliography

[0030] Chen, Fei C.; Ma, Estella P-M; Yiu, Edwin M-L (2014): Facial bone vibration in resonant voice production. In: Journal of voice : official journal of the Voice Foundation 28 (5), S. 596-602. DOI: 10.1016 / j.jvoice.2013.12.014.

[0031] Dickens, Paul; Smith, John; Wolfe, Joe (2007): Improved precision in measurements of acoustic impedance spectra using resonance-free calibration loads and controlled error distribution. In: The Journal of the AcousticalSociety of America 121 (3), S. 1471-1481. DOI: 10.1121 / 1.2434764.

[0032] Fant G. and Ishizaka; K.; -Lindqvist-Gauffin; J. and Sundberg; J. (1972): Subglottal formants. In: STL-QPSR 13 (1).

[0033] Hoyer, P.; Riedler, M.; Unterhofer, C.; Graf, S. (2022): Vocal Tract and Subglottal Impedance in High Performance Singing: A Case Study. In: J Voice. DOI: 10.1016 / j.jvoice.2022.01.015.

[0034] Inverse Vocal Tract Adjustment: Spectral Dependence and MRI Data (2020). ICVPB. Grenoble.

[0035] Noel Hanna, John Smith and Joe Wolfe (2018): How the acoustic resonances of the subglottal tract affect the impedance spectrum measured through the lips. In: Acoustical Society of America, S. 2639-2650. PHAM THI NGOC, Y.; BADIN, P. (1994): Vocal tract acoustic transfer function measurements : further developments and applications. In: J. Phys. IV France04 (C5), C5-549-C5-552. DOl: 10.1051 / jp4:19945118. Patentliteratur: DE 10 2017 000 570 B3 2018.07.05 DE 10 2018 000 554 A1 2018.09.13 ZITATE ENTHALTEN IN DER BESCHREIBUNG

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2017 000 570 B3 [0007, 0014, 0035] DE 10 2018 000 554 A1 [0007, 0014, 0035] Cited non-patent literature

[0000] Inverse Vocal Tract Adjustment: Spectral Dependence and MRI Data 2020; Hoyer et al. 2022

[0002] Noel Hanna, John Smith and Joe Wolfe 2018; Hoyer

[0007] Andrade et al. 2022

[0008] Chen, Fei C.; Ma, Estella P-M; Yiu, Edwin M-L (2014): Facial bone vibration in resonant voice production. In: Journal of voice : official journal of the Voice Foundation 28 (5), S. 596-602. DOI: 10.1016 / j.jvoice.2013.12.014

[0030] Dickens, Paul; Smith, John; Wolfe, Joe (2007): Improved precision in measurements of acoustic impedance spectra using resonance-free calibration loads and controlled error distribution. In: The Journal of the AcousticalSociety of America 121 (3), S. 1471-1481. DOI: 10.1121 / 1.2434764

[0031] Fant G. and Ishizaka; K.; -Lindqvist-Gauffin; J. and Sundberg; J. (1972): Subglottal formants. In: STL-QPSR 13 (1

[0032] Hoyer, P.; Riedler, M.; Unterhofer, C.; Graf, S. (2022): Vocal Tract and Subglottal Impedance in High Performance Singing: A Case Study. In: J Voice. DOI: 10.1016 / j.jvoice.2022.01.015

[0033] Inverse Vocal Tract Adjustment: Spectral Dependence and MRI Data (2020). ICVPB

[0034] Noel Hanna, John Smith and Joe Wolfe (2018): How the acoustic resonances of the subglottal tract affect the impedance spectrum measured through the lips. In: Acoustical Society of America, S. 2639-2650

[0035] PHAM THI NGOC, Y.; BADIN, P. (1994): Vocal tract acoustic transfer function measurements : further developments and applications. In: J. Phys. IV France04 (C5), C5-549-C5-552. DOl: 10.1051 / jp4:19945118

[0035]

Claims

[1] Device and method for improving the vocal sound or the improved playing of wind instruments, whereby resonances of the trachea below the glottis are stimulated by a mechanical surface vibration (wind instrument / structure-borne sound transducer / shaker) in the frequency range of the subglottal resonance frequencies, whereby the stimulation takes place on the skin of the user below the vocal folds. [2] Device and method according to claim 1 characterized by that a major part of the mechanical excitation lies in a frequency range above 200 Hz. [3] Device and method according to claim 1 characterized by that the frequency spectrum can be adapted to the subglottal resonances and / or the resonances of the vocal tract. [4] Device and method according to claim 1 characterized by that the use takes place during phonation or playing wind instruments. [5] Device and method according to claim 1 characterized bythat a microphone and / or an acceleration sensor applied to the skin records the acoustic signal and / or further processes it and / or visually prepares it for the user. [6] Device and method according to claim 1 characterized by that the use with visual stimulation procedures is supported by altered vocal tract settings or altered settings in the subglottal area. [7] Device and method according to claim 1 characterized by that the adjustment of the vocal tract and / or the subglottal area is recorded by an acoustic impedance measurement and / or the shape of the vocal tract or the subglottal area is supported by vibrations introduced via the mouth. [8] Device and method according to claim 1 characterized by that the resonance frequencies are in a defined phase relationship to each other when several resonances are excited. [9] Device for improving the sound of the voice or the improved playing of wind instruments, characterized by that the method features of claims 1 to 8 are implemented in a technical device. [10] A computer program comprising instructions causing the apparatus of claim 9 to carry out the method steps of claims 1 to 8.

Images