Showing papers in "Journal of the Acoustical Society of America in 1963"
TL;DR: In this paper, the theory of highly directional receivers and transmitters that may be constructed with the nonlinearity of the equations of fluid motion is presented, and the theory is extended to the case of a single antenna.
Abstract: This paper presents the theory of highly directional receivers and transmitters that may be “constructed” with the nonlinearity of the equations of fluid motion.
908 citations
TL;DR: In this article, an exponential function is used to describe the extent to which formant frequencies in the vowels reach their target values as a function of vowel segment duration. But the results suggest an interpretation in terms of a simple dynamic model of vowel articulation.
Abstract: Measurements of formant frequencies and duration are reported for 8 Swedish vowels uttered by a male talker in three consonantal environments under varying timing conditions. An exponential function is used to describe the extent to which formant frequencies in the vowels reach their target values as a function of vowel‐segment duration. A target is specified by the asymptotic values of the first two formant frequencies of the vowel and is independent of consonantal context and duration. It is thus an invariant attribute of the vowel. The results suggest an interpretation in terms of a simple dynamic model of vowel articulation.
808 citations
TL;DR: In this article, the authors examined the attenuation of the frequency spectral density and of the cross-spectral density associated with the second-order moments of the pressure field and showed that attenuation caused by the finite size of transducers is generally more sever.
Abstract: The finite size of a transducer‐sensing element limits its space resolution of a pressure field associated with a local turbulent flow. Such pressure fields are translated at a speed comparable to the characteristic velocity of the flow. Consequently, a lack of resolution in space causes an apparent inability to resolve in time. This problem—an example of the mapping of a random function of several variables by a linear operator—is examined here. With the help of a formalism which has been previously discussed and of some recent experimental information about the spatial structure of turbulent pressure fields in boundary layers, the mapping or distortion of statistical quantities associated with the second‐order moments of the pressure field is given. The attenuation of the frequency spectral density and of the cross‐spectral density is given explicitly in table form and in asymptotic form. The numerical results indicate that the attenuation caused by the finite size of transducers is generally more sever...
717 citations
TL;DR: In this article, a quantitative black-box model was developed for interpreting certain data on binaural masking level differences, and it was applied to data in which the signal to be detected consists of a pulsed tone, the masking signal consists of loud, broadband, Gaussian noise, and the only differences between the stimuli presented to the two ears are those of time delay or amplitude (the interaural amplitude ratios being restricted to unity or zero).
Abstract: In this paper, a quantitative “black‐box” model is developed for use in interpreting certain data on binaural‐masking‐level differences. The basic idea of this model is that the auditory system attempts to eliminate the masking components by first transforming the stimuli presented to the two ears so as to equalize the two masking components, and then subtracting. In order to obtain results that are quantitatively realistic, this processing is assumed to be corrupted by various types of errors. The model is applied to data in which the signal to be detected consists of a pulsed tone, the masking signal consists of loud, broad‐band, Gaussian noise, and the only differences between the stimuli presented to the two ears are those of time delay or amplitude (the interaural amplitude ratios being restricted to unity or zero). The results indicate that the ability of the auditory. system to control interaural intensity ratios and interaural time delays is limited to accuracies of about 1 dB and 150 μsec and that the auditory system has difficulty in compensating for interaural time delays greater than the time it takes for sound to travel a distance equal to the width of the head.
416 citations
TL;DR: It seems reasonable to conclude that responses to mechanical displacement of the skin are mediated by more than one receptor system, although direct evidence is still lacking.
Abstract: Vibrotactile thresholds were determined as a function of frequency, contactor configuration, and contactor area. It was found that contactor area is a more important stimulus parameter than the gradient or curvature of displacement. The absolute threshold for vibration seems to be independent of frequency when very small contactors are used and independent of area at low frequencies. For higher values of these parameters, it strongly depends on both. It seems reasonable to conclude that responses to mechanical displacement of the skin are mediated by more than one receptor system, although direct evidence is still lacking.
378 citations
TL;DR: Pitch perturbations were computed by measuring the differences between the durations of adjacent fundamental periods from recorded acoustic waveforms as mentioned in this paper, which may reflect variations in the waveshape of the glottal area wave.
Abstract: Pitch perturbations were computed by measuring the differences between the durations of adjacent fundamental periods from recorded acoustic waveforms. Sound‐synchronized high‐speed motion pictures of the vocal cords were also taken with a laryngeal mirror. It was found that pitch perturbations reflect variations in the waveshape of the glottal area wave, as well as variations in glottal periodicity. Perturbations having an absolute value ⩾0.5 msec are apparently induced by transients in the air‐pressure drop across the glottis, which may in turn be caused by changes in vocal‐tract configurations. Speakers with longer fundamental periods tend to have larger perturbations. The pitch perturbations of 23 speakers with pathologic larynges were measured. Certain of the speakers who had pathologic growths on their vocal cords had larger pitch perturbations than did normal speakers with the same median fundamental periods. The “perturbation factor,” which was defined as the percent that perturbations ⩾0.5 msec oc...
314 citations
TL;DR: In this article, a nonlinear elasticity theory is used to investigate the scattering of two intersecting, plane, elastic waves in a homogeneous, isotropic medium, and a criterion for the occurrence of a strong scattered wave is derived.
Abstract: Nonlinear elasticity theory is used to investigate the scattering of two intersecting, plane, elastic waves in a homogeneous, isotropic medium. A criterion for the occurrence of a strong scattered wave is derived. The criterion is formulated as a relationship between the first‐order elastic constants of the material, the angle between the intersecting wave vectors, and the ratio of wave frequencies. The exact formulation also depends on the type of intersecting waves, i.e., longitudinal or transverse. The amplitude of the scattered wave is found to be proportional to the volume of interaction and dependent on the third‐order elastic constants of the material. Numerical results are given for wave scattering polystyrene.
251 citations
TL;DR: In this article, the authors proposed a threshold for rectified diffusion of a gas-filled bubble in a liquid to counteract the effect of diffusion for values of the acoustic pressure amplitude greater than some threshold value, which was determined by using computed radius-time curves for bubbles pulsating nonlinearly rather than assumed infinitesimal, sinusoidal motions.
Abstract: A gas‐filled bubble in a liquid will generally dissolve because of diffusion of gas out of the bubble into the surrounding liquid. However, when set into motion by an acoustic field, a bubble may grow by a process called rectified diffusion. This process can counteract the effect of diffusion for values of the acoustic‐pressure amplitude greater than some threshold value. This threshold has been determined by a theory that uses computed radius‐time curves for bubbles pulsating nonlinearly rather than assumed infinitesimal, sinusoidal motions. For radius‐time curves calculated by a digital computer, this threshold has been computed for a sequence of values of gas concentration, bubble radius, and acoustic frequency. [This work was supported by the U. S. Office of Naval Research (Code 468).]
240 citations
TL;DR: In this article, a monaural loudness function was determined for 1000 cps and compared to a previously obtained binaural one, and the empirical evidence does not permit rejection of the hypothesis of a simple interaural summation.
Abstract: A monaural loudness function is determined for 1000 cps and compared to a previously obtained binaural loudness function. Although the monaural function appears to have a somewhat smaller exponent than the binaural one, the empirical evidence does not permit rejection of the hypothesis of a simple interaural loudness summation. The psychophysical methods of magnitude estimation with and without a designated standard and of magnitude production without standards are used. A combination of magnitude estimation and production without standards is accepted as a method with minimum bias and classified under a more general methodological category called “psychological magnitude balance.”
229 citations
TL;DR: For example, this article showed that when a stimulus word is only a few decibels below its intelligibility threshold, many of its features such as the number of syllables, for example, are still perceived correctly.
Abstract: The following interpretation of the word frequency effect—the tendency for common words to be perceived correctly at much lower speech to‐noise ratios than uncommon words—was proposed and verified experimentally. When a stimulus word is only a few decibels below its intelligibility threshold, many of its features—the number of syllables, for example—are still perceived correctly. If enough such features are heard, then only a small number of English words will be consistent with them. Subjects' incorrect responses will be taken from that small set of words, and furthermore they will usually be the relatively common words in the set. If the stimulus is an uncommon word and there are common English words that are phonetically quite similar to it, then these common words will usually be given as (incorrect) responses except at quite high speech‐to noise ratios. This interpretation is confirmed by an analysis of errors in an articulation test. The results show that all subjects tend to give the same incorrect responses, that these incorrect responses are usually more common than the stimuli to which they were given, and that, when a word is not confused with another in this way, its threshold is relatively low regardless of its frequency of occurrence in English usage.
185 citations
TL;DR: Single unit recordings from the eighth nerve of the bullfrog reveal two strikingly different kinds of auditory units, both of which exhibit sharply frequency dependent sensitivity (tuning curves).
Abstract: Single unit recordings from the eighth nerve of the bullfrog reveal two strikingly different kinds of auditory units. Both kinds of units exhibit sharply frequency dependent sensitivity (tuning curves). “Simple” units are maximally sensitive to tone bursts of frequency between 1000 and 1500 cps. Their frequency sensitivity and their capacity to “follow” pulse stimuli are well‐matched to the spectral composition and pitch period, respectively, of the bullfrog's croak. Simple units cannot be inhibited by acoustic stimuli. “Complex” units are inhibited by acoustic signals in the frequency range from 300 to 1000 cps. Some complex units are excited by acoustic stimuli, some are excited by both acoustic and vibratory stimuli, and some are excited by vibratory stimuli alone. Complex units that can be excited by sound are most sensitive to frequencies between 200 and 700 cps. Simple and complex units probably derive from separate sense organs (the basilar and amphibian papillae, respectively) within the otic capsule. There is evidence that all of these responses are from primary neurons; moreover, it has been shown that the inhibition is not under efferent control. Extremely sensitive units of both types are found with thresholds comparable to those of human listeners. Responses to tone bursts, noise bursts, click trains, and frog croaks are compared. The roles of spectral and temporal pattern of the stimulus in determining the response of a unit are explored.
TL;DR: In this article, the Fokker-Planck equation is applied to discrete nonlinear dynamic systems subjected to white random excitation and it is shown that exact solutions can be constructed for the stationary version.
Abstract: The Fokker-Planck equation is derived and applied to discrete nonlinear dynamic systems subjected to white random excitation. For the class of problems in which the nonlinearities involve only the displacements of the system, it is shown that exact solutions can be constructed for the stationary Fokker-Planck equation. It is further shown that if stationary solutions exist they are unique.
TL;DR: This article found that an increase of subglottal pressure of about 6.5 cm aq accompanied an increase in frequency of half an octave; and to a first approximation (rate of flow) ∝ (subglotta pressure) ∈ (effective sound pressure)1.2, suggesting that subjects assessed the work done and not the auditory sensation in the usual way as found by Lane, Catania and Stevens.
Abstract: Three experiments using one speaker and 30 listeners provided correlated data on subglottal pressure, average volume velocity through the glottis, fundamental frequency, effective sound pressure in front of the speaker, and judgments of loudness. Experiment 1: In 12 repetitions each of bee, bay, bar, bore, and boo spoken at various loudnesses, it was found that in the middle range (subglottal pressure) ∝ (effective sound pressure)0.6; and the level of the vowel in bar was about 5 dB greater than in bee or boo produced with the same subglottal pressure. Experiment 2: In 32 repetitions of the vowel /ɑ/ uttered at various loudnesses with the pitch uncontrolled, it was found that an increase of subglottal pressure of about 6.5 cm aq accompanied an increase in frequency of half an octave; and to a first approximation (rate of flow) ∝ (subglottal pressure). It follows that (rate of work done on the air) ∝ (subglottal pressure)2 ∝ (effective sound pressure)1.2. The exponent 1.2 compares well with the exponent 1.1 found by Lane, Catania, and Stevens for the autophonic response. Experiment 3: Thirty subjects judged the loudness of each word taken from Experiment 1 relative to the reference token in the frame Compare the words: bar and …. It was found that for any one vowel in the middle range, (loudness) ∝ (effective sound pressure)1.2, suggesting that subjects assessed the work done and not the auditory sensation in the usual way as found by Lane, Catania, and Stevens.
TL;DR: In this article, the classical perturbation method was applied to the random response of vibratory systems that are only slightly nonlinear, and the results were shown to be more complete when the damping remains linear.
Abstract: The random response of vibratory systems that are only slightly nonlinear may be conveniently obtained by applying the classical perturbation method. The present paper describes and illustrates the procedure. Oscillators with nonlinearity in the stiffness elements are treated first because more‐complete results can be obtained when the damping remains linear. Then, systems with more‐general nonlinearities are examined. The techniques are illustrated by applications to simple one‐ and two‐degree‐of‐freedom, nonlinear, vibratory systems.
TL;DR: In this paper, a method of analysis is presented for predicting sound radiation from an arbitrary body (shell) vibrating in an infinite fluid medium, where the acoustic field is described by a distribution of surface sources of unknown strength at the shell fluid boundaries, leading to a set of integral equations.
Abstract: A method of analysis is presented for predicting sound radiation from an arbitrary body (shell) vibrating in an infinite fluid medium. The acoustic field is described by a distribution of surface sources of unknown strength at the shell fluid boundaries, which leads to a set of integral equations. In the general case, the shell with or without an attached internal structure is described by an elastic system having a finite number of degrees of freedom. The dynamic interaction between the shell and the fluid at their boundaries is then formulated in terms of the unknown strength of the source distribution. By matrix analysis, the method has been formalized and coded in the digital computer for computation.Numerical results of two examples are presented to demonstrate the versatility of the method, which makes possible the solution of a large class of sound radiation problems.
TL;DR: Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering, 1963.
Abstract: Acoustic clicks were presented through earphones to the two ears of anesthetized cats, and the electrical response activity of single nerve cells in the accessory nucleus of the superior olive was studied. Stimulus parameters investigated included interaural time difference, interaural intensity difference, and average intensity. Attention was concentrated on cells that were excited by stimulation of the contralateral ear and inhibited by stimulation of the ipsilateral ear. The experimental results are incorporated into van Bergeijk's model for binaural interaction, for which it is postulated that localization judgments are obtained on the basis of a comparison of the amounts of response activity in the two accessory nuclei. The model yields predictions that are in agreement with results from human psychophysics. The model predicts that the virtual image should be lateralized toward the side receiving prior or more intense stimulation. A time‐intensity trading relationship that is in agreement with results from “centering” experiments is derived. The model predicts minimum detectable changes in interaural time difference of 5–10 μsec and minimum detectable changes in interaural intensity difference of 0.1–0.5 dB.
TL;DR: In this article, the noise reduction produced by a small rigid enclosure with one flexible wall is computed for very low frequencies where both wall and enclosed volume are stiffness controlled, for frequencies where the wall is resonant and the volume is stiff, and for frequency where both the wall and the acoustic space have resonant behavior.
Abstract: The noise reduction produced by a small rigid enclosure with one flexible wall is computed. It is assumed that the critical frequency of the wall lies above the first acoustic resonance of the enclosure. The noise reduction is computed for very low frequencies where both wall and enclosed volume are stiffness‐controlled, for frequencies where the wall is resonant and the volume is stiff, and for frequencies where both the wall and the acoustic space have resonant behavior. In the last case, a comparison made with the usual noise‐reduction calculations based on forced wave‐transmission loss. The noise reduction computed in this paper turns out to be less than the value computed by that more “classical” approach.
TL;DR: In this article, the authors used an iterated, uninterrupted section of random noise and found that periodicity (iteration) is easily detectable to about 1 cps and detectable with especial difficulty below 0.5 cps.
Abstract: Tests utilizing an iterated, uninterrupted section of random noise disclose that periodicity (iteration) is easily detectable to about 1 cps and detectable with especial difficulty below 0.5 cps. Frequencies bounding regions of perception of pitch, motorboating, and whooshing are specified as 19, 4, and 1 cps, respectively.
TL;DR: In this article, the radiation field of a body vibrating with a specified distribution of velocity on the surface can be computed from the Helmholtz integral if the pressure distribution on surface is known.
Abstract: The radiation field of a body vibrating with a specified distribution of velocity on the surface may be computed from the Helmholtz integral if the pressure distribution on the surface is known In special cases of low frequency, high frequency, or particular surface shapes, it is possible to estimate the surface pressures with sufficient accuracy and thus reduce the calculation of the field pressure to a simple quadrature over the surface In more‐general cases, the surface pressure may be calculated by numerical solution of a Fredholm integral equation This solution is described in detail for the special case of a surface of revolution with an arbitrary velocity distribution and frequency The numerical solutions are illustrated by particular examples and compared with exact analyses
TL;DR: In this article, a variety of statistical information about spoken English was obtained by analyzing a considerable body of conversational material and narrative taken from "Phonetic Readers"; the analyses were carried out by using a digital computer.
Abstract: A variety of statistical information about spoken English was obtained. The data are the results of analyzing a considerable body of conversational material and narrative taken from “Phonetic Readers”; the analyses were carried out by using a digital computer. The principles for selecting the speech material are discussed. Counts were obtained for the frequency of occurrence of phonemes, for the digram frequencies of phonemes, for word length, etc. Stress was taken into consideration, and many of the statistics were obtained separately for stressed and unstressed syllables. In addition, the frequency distribution of minimal pairs was obtained. Minimal pairs are the phoneme pairs that minimally distinguish one word from another. All results were evaluated from the articulatory point of view. It was found that, in spoken English, dental and alveolar articulations predominate and that manner rather than place of articulation is the dimension that carries by far the greatest functional load.
TL;DR: A theory of ultrasonic atomization of liquid films is presented in this paper, where it is assumed that exponential growth of surface disturbances ultimately results in the formation of liquid drops, the diameters of which are proportional to the wavelength of the most rapidly growing initial disturbance.
Abstract: A theory of ultrasonic atomization of liquid films is presented. It is assumed that exponential growth of surface disturbances ultimately results in the formation of liquid drops, the diameters of which are proportional to the wavelength of the most rapidly growing initial disturbance. The hydrodynamic stability equations of the liquid film are examined, and the most rapidly growing initial disturbances are determined by numerical solution in the unstable region. A resultant correlation between drop size, transducer frequency, transducer amplitude, and liquid‐film thickness is obtained. Results are compared to previous theoretical and experimental conclusions.
TL;DR: In this paper, a pattern-matching procedure for automatic recognition of talkers was used to study the effects of variations in patterns upon recognition performance, and the same pattern was used with patterns reduced to two dimensions.
Abstract: A pattern‐matching procedure for automatic recognition of talkers was used to study the effects of variations in patterns upon recognition performance. Several utterances of common words, excerpted from context, were spoken by ten talkers and converted to time‐frequency‐energy patterns. Some of each talker's utterances were used to form reference patterns and the remaining utterances served as test patterns. The recognition procedure consisted of cross‐correlating the test patterns with the reference patterns and selecting the talker corresponding to the reference pattern with the highest correlation as the talker of the test utterance. The same recognition procedure was used with patterns reduced to two dimensions. The recognition score for three‐dimensional patterns was 89%. Reducing the original patterns to time‐energy patterns resulted in a lower recognition score; however, when only spectral information was retained, recognition results were the same as those for three‐dimensional patterns. No errors were made in recognition based on a small sample of patterns consisting of pooled spectra of several different voiced sounds.
TL;DR: In this article, the scattered field due to an acoustic wave impinging on an arbitrarily shaped cylinder is calculated using integral equations, and the results are compared with those obtained from an eigenfunction expansion for the scattered wave from a right circular cylinder.
Abstract: Using integral equations, the scattered field due to an acoustic wave impinging on an arbitrarily shaped cylinder is calculated. The equations are solved by finite difference methods, and the results are compared with those obtained from an eigenfunction expansion for the scattered wave from a right circular cylinder. Both nearfield and farfield results are presented for other cross sections.
TL;DR: In this article, the problem of wave propagation in an infinite piezoelectric plate belonging to crystallographic class C6v, situated between shorted electrodes, is rigorously analyzed for two special orientations of the sixfold axis.
Abstract: The problem of wave propagation in an infinite piezoelectric plate belonging to crystallographic class C6v, situated between shorted electrodes, is rigorously analyzed for two special orientations of the sixfold axis. The solution is derived using the linear piezoelectric equations. The analysis shows that for a given frequency and wave number in the propagation direction there are three independent solutions of the differential equations, and, furthermore, that these three solutions couple at the traction‐free boundaries of the plate. The dispersion curves can be calculated from the resulting transcendental equations. It has previously been shown that the resonant frequencies at infinite wavelength of a plate, in which the electromechanical coupling factors are high, deviate considerably from those of the purely elastic solution. Thus the dispersion spectrum calculated from this analysis will deviate considerably from that of the purely elastic analysis. It is shown in an appendix that the solution for t...
TL;DR: In this paper, the amplitude and phase angle of vibration of the malleus, incus, and round window for constant sound pressure level at the eardrum was measured by a capacitive probe.
Abstract: The transfer function of the middle ear was investigated in anesthetized cats. The amplitude and phase angle of vibration of the malleus, incus, and round window for constant sound‐pressure level at the eardrum was measured by a capacitive probe. The acoustic impedance at the eardrum in the frequency range from 200 to 8000 cps was also measured. The acoustic impedance at the eardrum was found to be proportional to the ratio of sound pressure at the eardrum and velocity of the malleus from about 200 cps to 4 kc/sec, showing that the eardrum acts as a rigid piston in this frequency region. By comparing the amplitude of the malleus and that of the round window, it was found that the coupling between the malleus and the cochlear fluid is very rigid. A second‐order low‐pass function described by its Laplace transform was found to be a good approximation to the experimental data, up to a frequency of about 4 kc/sec, or approximately 4 times the cutoff frequency. In the frequency range where the eardrum acts as a rigid piston, it is thus possible to estimate the transfer function of the middle ear entirely from the acoustic impedance data in the plane of the eardrum.
TL;DR: In this paper, a detailed description of how the distribution of the energy-flux density changes as the wave motion corresponding to the second branch of roots goes from the region of forward wave motion to the regions of backward wave motion is given.
Abstract: The propagation characteristics of longitudinal modes are described by the Pochhammer frequency equation, in the case of elastic cylinders, and the Rayleigh‐Lamb frequency equation, in the case of elastic plates. The longitudinal modes in both geometries are closely analogous. In both cases, the second branch of the mode spectrum determined by the roots of the applicable frequency equation shows a region in which phase and group velocities have opposite signs. Wavemotions having phase and group velocities of opposite sign occur in certain guided, electromagnetic wavemotions and are often referred to as backward wavemotions. This paper reports experimental observations of stress pulses traveling in backward, elastic wavemotions in cylinders and plates. Also included in the paper is a detailed description of how the distribution of the energy‐flux density changes as the wavemotion corresponding to the second branch of roots goes from the region of forward wavemotion to the region of backward wavemotion.
TL;DR: Several auditory phenomena, such as pitch, volume, tonal localization, and analogies between the ear and the skin, are discussed in the framework of the place and the periodicity theories of hearing as mentioned in this paper.
Abstract: Several auditory phenomena—pitch, tonal volume, tonal localization, and analogies between the ear and the skin—are discussed in the framework of the place and the periodicity theories of hearing.
TL;DR: In this article, an electrical network analog for the guinea pig ear was developed, which is similar to that developed previously for the human ear and can be used for the determination of transient responses.
Abstract: An electrical network analog is developed for the guinea‐pig ear. The analog is similar to that developed previously for the human ear. The network is based on the anatomy and on impedance measurements. Its input impedance and transmission characteristic are in approximate agreement with those of the real ear. It is shown how the analog can be used for the determination of transient responses.
TL;DR: Equal-noisiness experiments using variable sound durations and pressure levels to determine perceived noise level of listeners were conducted in this article, where variable sound duration and pressure level were used.
Abstract: Equal-noisiness experiments using variable sound durations and pressure levels to determine perceived noise level of listeners
TL;DR: A theory of the clarinet is developed based on the experimental observation that the reed and air column vibrations are nearly sinusoidal as discussed by the authors. But this theory assumes that the air column is a cylindrical air column with a diaphragm containing a slit of variable width.
Abstract: A theory of the clarinet is developed based on the experimental observation that for weak tones the reed and air‐column vibrations are nearly sinusoidal. The clarinet is assumed to be a cylindrical air column open at one end and closed at the other by a diaphragm containing a slit of variable width, corresponding to the aperture between reed and mouthpiece. A velocity potential appropriate to a tube with wall friction is assumed. The impedance of the slit as a function of opening and pressure across it is evaluated experimentally and checked against theory. The volume flow through the slit is calculated from the velocity potential and equated to the flow calculated from the slit impedance. The flow and impedance both depend on the pressure, which in turn is again calculated from the velocity potential. Expressions for the operating frequency and threshold blowing pressure are obtained by assuming the flow to consist of a small alternating component superimposed on a steady component. The frequency is found to be below the resonance of the system considered as a tube closed at the reed end, the shift varying nearly linearly with the slit opening and depending on the reed damping. The threshold blowing pressure is found to be proportional to the opening and to the reed stiffness. Operating frequencies and pressures for the artificially blown clarinet were measured experimentally and found to be in very good agreement with values calculated from the theory.