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  • 1. Alku, Paavo
    et al.
    Airas, Matti
    Björkner, Eva
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Sundberg, Johan
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    An amplitude quotient based method to analyze changes in the shape of the glottal pulse in the regulation of vocal intensity2006Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 120, nr 2, s. 1052-1062Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study presents an approach to visualizing intensity regulation in speech. The method expresses a voice sample in a two-dimensional space using amplitude-domain values extracted from the glottal flow estimated by inverse filtering. The two-dimensional presentation is obtained by expressing a time-domainmeasure of the glottal pulse, the amplitude quotient (AQ), as a function of the negative peak amplitude of the flow derivative (d(peak)). The regulation of vocal intensity was analyzed with the proposed method from voices varying from extremely soft to very loud with a SPL range of approximately 55 dB. When vocal intensity was increased, the speech samples first showed a rapidly decreasing trend as expressed on the proposed AQ-d(peak) graph. When intensity was further raised, the location of the samples converged toward a horizontal line, the asymptote of a hypothetical hyperbola. This behavior of the AQ-d(peak) graph indicates that the intensity regulation strategy changes from laryngeal to respiratory mechanisms and the method chosen makes it possible to quantify how control mechanisms underlying the regulation of vocal intensity change gradually between the two means. The proposed presentation constitutes an easy-to-implement method to visualize the function of voice production in intensity regulation because the only information needed is the glottal flow wave form estimated by inverse filtering the acoustic speech pressure signal.

  • 2.
    Arnela, Marc
    et al.
    GTM–Grup de recerca en Tecnologies Mèdia, La Salle, Universitat Ramon Llull, C/Quatre Camins 30, Barcelona, E-08022, Catalonia, Spain.
    Blandin, Rémi
    GIPSA-Lab, Unité Mixte de Recherche au Centre National de la Recherche Scientifique 5216, Grenoble Campus, St. Martin d'Heres, F-38402, France.
    Dabbaghchian, Saeed
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Tal-kommunikation.
    Guasch, Oriol
    GTM–Grup de recerca en Tecnologies Mèdia, La Salle, Universitat Ramon Llull, C/Quatre Camins 30, Barcelona, E-08022, Catalonia, Spain.
    Alías, Francesc
    GTM–Grup de recerca en Tecnologies Mèdia, La Salle, Universitat Ramon Llull, C/Quatre Camins 30, Barcelona, E-08022, Catalonia, Spain.
    Pelorson, Xavier
    GIPSA-Lab, Unité Mixte de Recherche au Centre National de la Recherche Scientifique 5216, Grenoble Campus, St. Martin d'Heres, F-38402, France.
    Van Hirtum, Annemie
    GIPSA-Lab, Unité Mixte de Recherche au Centre National de la Recherche Scientifique 5216, Grenoble Campus, St. Martin d'Heres, F-38402, France.
    Engwall, Olov
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Tal-kommunikation.
    Influence of lips on the production of vowels based on finite element simulations and experiments2016Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 139, nr 5, s. 2852-2859Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Three-dimensional (3-D) numerical approaches for voice production are currently being investigated and developed. Radiation losses produced when sound waves emanate from the mouth aperture are one of the key aspects to be modeled. When doing so, the lips are usually removed from the vocal tract geometry in order to impose a radiation impedance on a closed cross-section, which speeds up the numerical simulations compared to free-field radiation solutions. However, lips may play a significant role. In this work, the lips' effects on vowel sounds are investigated by using 3-D vocal tract geometries generated from magnetic resonance imaging. To this aim, two configurations for the vocal tract exit are considered: with lips and without lips. The acoustic behavior of each is analyzed and compared by means of time-domain finite element simulations that allow free-field wave propagation and experiments performed using 3-D-printed mechanical replicas. The results show that the lips should be included in order to correctly model vocal tract acoustics not only at high frequencies, as commonly accepted, but also in the low frequency range below 4 kHz, where plane wave propagation occurs.

  • 3. Arnela, Marc
    et al.
    Dabbaghchian, Saeed
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Blandin, Rémi
    Guasch, Oriol
    Engwall, Olov
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Hirtum, Annemie Van
    Pelorson, Xavier
    Influence of vocal tract geometry simplifications on the numerical simulation of vowel sounds2016Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 140, nr 3, s. 1707-1718Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For many years, the vocal tract shape has been approximated by one-dimensional (1D) area functions to study the production of voice. More recently, 3D approaches allow one to deal with the complex 3D vocal tract, although area-based 3D geometries of circular cross-section are still in use. However, little is known about the influence of performing such a simplification, and some alternatives may exist between these two extreme options. To this aim, several vocal tract geometry simplifications for vowels [ɑ], [i], and [u] are investigated in this work. Six cases are considered, consisting of realistic, elliptical, and circular cross-sections interpolated through a bent or straight midline. For frequencies below 4–5 kHz, the influence of bending and cross-sectional shape has been found weak, while above these values simplified bent vocal tracts with realistic cross-sections are necessary to correctly emulate higher-order mode propagation. To perform this study, the finite element method (FEM) has been used. FEM results have also been compared to a 3D multimodal method and to a classical 1D frequency domain model.

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  • 4. Auregan, Yves
    et al.
    Farooqui, Maaz
    Groby, Jean-Phillipe
    Low frequency sound attenuation in a flow duct using a thin slow sound material2016Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 139, nr 5, s. EL149-EL153Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A thin subwavelength material that can be flush mounted in a duct and that gives an attenuation band at low frequencies in air flow channels is presented. To decrease the material thickness, the sound is slowed in the material using folded side branch tubes. The impedance of the material is compared to the optimal value given by the Cremer condition, which can differ greatly from the air characteristic impedance. Grazing flow on this material increases the losses at the interface between the flow and the material.

  • 5.
    Bjurström, Henrik
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Rydén, Nils
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Jord- och bergmekanik.
    Detecting the thickness mode frequency in a concrete plate using backward wave propagation2016Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 139, nr 2, s. 649-657Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Material stiffness and plate thickness are the two key parameters when performing quality assurance/quality control on pavement structures. In order to estimate the plate thickness non-destructively, theImpact Echo (IE) method can be utilized to extract the thickness resonance frequency. An alternativeto IE for estimating the thickness resonance frequency of a concrete plate, and to subsequently enablethickness determination, is presented in this paper. The thickness resonance is often revealed as asharp peak in the frequency spectrum when contact receivers are used in seismic testing. Due to a lowsignal-to-noise ratio, IE is not ideal when using non-contact microphone receivers. In studying thecomplex Lamb wave dispersion curves at a frequency infinitesimally higher than the thickness frequency,it is seen that two counter-directed waves occur at the same frequency but with phase velocitiesin opposite directions. Results show that it is possible to detect the wave traveling with anegative phase velocity using both accelerometers and air-coupled microphones as receivers. Thisalternative technique can possibly be used in non-contact scanning measurements based on aircoupled microphones.

  • 6.
    Bodén, Hans
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Strukturakustik.
    Experimental source characterization techniques for studying the acoustic properties of perforates under high level acoustic excitation2011Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 130, nr 5, s. 2639-2647Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper discusses experimental techniques for obtaining the acoustic properties of in-duct samples with non-linear acoustic characteristic. The methods developed are intended both for studies of non-linear energy transfer to higher harmonics for samples only accessible from one side such as wall treatment in aircraft engine ducts or automotive exhaust systems and for samples accessible from both sides such as perforates or other top sheets. When harmonic sound waves are incident on the sample nonlinear energy transfer results in sound generation at higher harmonics at the sample (perforate) surface. The idea is that these sources can be characterized using linear system identification techniques similar to one-port or two-port techniques which are traditionally used for obtaining source data for in-duct sources such as IC-engines or fans. The starting point will be so called polyharmonic distortion modeling which is used for characterization of nonlinear properties of microwave systems. It will be shown how acoustic source data models can be expressed using this theory. Source models of different complexity are developed and experimentally tested. The results of the experimental tests show that these techniques can give results which are useful for understanding non-linear energy transfer to higher harmonics.

  • 7.
    Boij, Susann
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet. KTH, Skolan för teknikvetenskap (SCI), Centra, Linné Flow Center, FLOW.
    Flow effects on the acoustic end correction of a sudden in-duct area expansion2009Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 126, nr 3, s. 995-1004Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For scattering of plane waves at a sudden area expansion in a duct, the presence of flow may significantly alter the reactive properties. This paper studies the influence of a mean flow field and unstable separated flow on the reactive properties of the expansion, formulated as an end correction. Theoretical and experimental results show that the expansion end correction is significantly affected by the flow and hydrodynamic waves excited at the edge of the expansion. The effects are different in three regions where the Strouhal number is small, of order 1, and large. The influence is most significant at Strouhal numbers of the order 1, with specific limiting values for large and small Strouhal numbers, respectively. In the analytic model, an important feature is the shear layer at the edge modeled as a vortex sheet with the unsteady Kutta condition applied at the edge. The influence of Mach number, Helmholtz number, and area expansion ratio is studied, and a quasistationary, small Strouhal number, approximation yields an expression for the end correction. Further, the influence of edge condition is explored, emphasizing the importance of interaction between sound and unsteady vorticity shedding at the edge of the area expansion.

  • 8.
    Bolin, Karl
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Almgren, Martin
    Ohlsson, Esbjörn
    Karasalo, Ilkka
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Long term estimations of low frequency noise levels over water from an off-shore wind farm2014Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 135, nr 3, s. 1106-1114Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article focuses on computations of low frequency sound propagation from an off-shore wind farm. Two different methods for sound propagation calculations are combined with meteorological data for every 3 hours in the year 2010 to examine the varying noise levels at a reception point at 13 km distance. It is shown that sound propagation conditions play a vital role in the noise impact from the off-shore wind farm and ordinary assessment methods can become inaccurate at longer propagation distances over water. Therefore, this paper suggests that methodologies to calculate noise immission with realistic sound speed profiles need to be combined with meteorological data over extended time periods to evaluate the impact of low frequency noise from modern off-shore wind farms.

  • 9.
    Bolin, Karl
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Boue, Mathieu
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Karasalo, Ilkka
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Long range sound propagation over a sea surface2009Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 126, nr 5, s. 2191-2197Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper describes methodology and results from a model-based analysis of data on sound transmission from controlled sound sources at sea to a 10-km distant shore. The data consist of registrations of sound transmission loss together with concurrently collected atmospheric data at the source and receiver locations. The purpose of the analysis is to assess the accuracy of methods for transmission loss prediction in which detailed data on the local geography and atmospheric conditions are used for computation of the sound field. The results indicate that such sound propagation predictions are accurate and reproduce observed variations in the sound level as function of time in a realistic way. The results further illustrate that the atmospheric model must include a description of turbulence effects to ensure predicted noise levels to remain realistically high during periods of sound shadow. (C) 2009 Acoustical Society of America. [DOI: 10.1121/1.3238236]

  • 10.
    Bolin, Karl
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik, Strömningsmekanik och Teknisk Akustik, Marcus Wallenberg Laboratoriet MWL.
    Conrady, K.
    Ilkka, Karasalo
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik, Strömningsmekanik och Teknisk Akustik, Marcus Wallenberg Laboratoriet MWL.
    Sjöblom, A.
    An investigation of the influence of the refractive shadow zone on wind turbine noise2020Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 148, nr 2, s. EL166-EL171Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article aims to investigate if the proportion of the rotor area of a wind turbine that is in the refractive shadow zone according to a ray tracing algorithm coupled to meteorological forecast data is correlated to sound levels and amplitude modulation. The acoustic station is situated 950 m from a wind farm in Northern Sweden and the measurement period is seven months. On average, 1.9 dBA lower sound levels are measured when the part of the rotor disk of the closest turbine is in the refractive shadow zone. A higher probability of amplitude modulations are observed when around half of the turbine rotor is within the refractive shadow zone compared to conditions with no shadow zone present.

  • 11.
    Bolin, Karl
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Åbom, Mats
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Air-borne sound generated by sea waves2010Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 127, nr 5, s. 2771-2779Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper describes a semi-empiric model and measurements of air-borne sound generated by breaking sea waves. Measurements have been performed at the Baltic Sea. Shores with different slopes and sediment types have been investigated. Results showed that the sound pressure level increased from 60 dB at 0.4 m wave height to 78 dB at 2.0 m wave height. The 1/3 octave spectrum was dependent on the surf type. A scaling model based on the dissipated wave power and a surf similarity parameter is proposed and compared to measurements. The predictions show satisfactory agreement to the measurements. (C) 2010 Acoustical Society of America. [DOI: 10.1121/1.3327815]

  • 12.
    Cartling, Bo
    KTH, Skolan för teknikvetenskap (SCI), Fysik.
    Beating frequency and amplitude modulation of the piano tone due to coupling of tones2005Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 117, nr 4, s. 2259-2267Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The influence on a piano tone from weak coexcitation of damped adjacent tones due to coupling via the bridge is studied. The frequency and amplitude modulation of the sound resulting from coexcitation of one strong and one or two weak tones is analyzed. One weak tone causes frequency and amplitude modulation of the sound, and two weak tones produce beating frequency and amplitude modulation, where the beatings of the two modulations are of opposite phase. By digital recording of the sound of piano tones, the appearance of these phenomena is verified. The audibility of the observed frequency and amplitude modulation is discussed in terms of previously determined detection thresholds. The beating character of both frequency and amplitude modulations, however, distinguishes the phenomena from those previously studied and prompts further psychoacoustic investigations. It is shown that detuning of unison strings may significantly increase the frequency deviation of the frequency modulation in conjunction with affected amplitude modulation. The modulatory effects of coupling to adjacent tones therefore may possibly be utilized in the tuning process. A coupling of tones analogous to the situation in a piano may arise in other stringed musical instruments transferring string vibrations to a soundboard via a bridge.

  • 13.
    Cuenca, Jacques
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Göransson, Peter
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Inverse estimation of the elastic and anelastic properties of the porous frame of anisotropic open-cell foams2012Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 132, nr 2, s. 621-629Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents a method for simultaneously identifying both the elastic and anelastic properties of the porous frame of anisotropic open-cell foams. The approach is based on an inverse estimation procedure of the complex stiffness matrix of the frame by performing a model fit of a set of transfer functions of a sample of material subjected to compression excitation in vacuo. The material elastic properties are assumed to have orthotropic symmetry and the anelastic properties are described using a fractional-derivative model within the framework of an augmented Hooke's law. The inverse estimation problem is formulated as a numerical optimization procedure and solved using the globally convergent method of moving asymptotes. To show the feasibility of the approach a numerically generated target material is used here as a benchmark. It is shown that the method provides the full frequency-dependent orthotropic complex stiffness matrix within a reasonable degree of accuracy.

  • 14.
    Dahl, Sofia
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Granqvist, Svante
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Ability to determine continuous drift in auditory sequences: Evidence for bias in listeners' perception of tempo2005Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524Artikel i tidskrift (Övrigt vetenskapligt)
  • 15.
    Dickson, Crispin
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    A method for time-varying annoyance rating of aircraft noise2009Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 126, nr 1, s. 1-3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The method of continuous judgment by category is used and evaluated to measure time-varying attributes in aircraft flyover sounds. The results are also used to estimate preference between the different experimental sounds. Jurors were asked to rate perceived annoyance on a Borg CR 100 scale continuously during the playback of 11 flyover sequences and the results showed differences in perception in the time segment where the sound had been modified. The method can be used to evaluate maximum perceived annoyance, threshold levels, duration of perceptual presence temporal integration in perception, and perceptual mixtures over time.

  • 16.
    Drioli, Carlo
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    A flow waveform-matched low-dimensional glottal model based on physical knowledge2005Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 117, nr 5, s. 3184-3195Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of this study is to explore the possibility for physically based mathematical models of the voice source to accurately reproduce inverse filtered glottal volume-velocity waveforms. A low-dimensional, self-oscillating model of the glottal source with waveform-matching properties is proposed. The model relies on a lumped mechano-aerodynamic scheme loosely inspired by the one-and multimass lumped models. The vocal folds are represented by a single mechanical resonator and a propagation line which takes into account the vertical phase differences. The vocal-fold displacement is coupled to the glottal flow by means of an aerodynamic driving block which includes a general parametric nonlinear component. The principal characteristics of the flow-induced oscillations are retained, and the overall model is able to match inverse-filtered glottal flow signals. The method offers in principle the possibility of performing transformations of the glottal flow by acting on the physiologically based parameters of the model. This is a desirable property, e.g., for speech synthesis applications. The model was tested on a data set which included inverse-filtered glottal flow waveforms of different characteristics. The results demonstrate the possibility of reproducing natural speech waveforms with high accuracy, and of controlling important characteristics of the synthesis such as pitch.

  • 17. Echternach, Matthias
    et al.
    Doellinger, Michael
    Sundberg, Johan
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Traser, Louisa
    Richter, Bernhard
    Vocal fold vibrations at high soprano fundamental frequencies2013Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 133, nr 2, s. EL82-EL87Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Human voice production at very high fundamental frequencies is not yet understood in detail. It was hypothesized that these frequencies are produced by turbulences, vocal tract/vocal fold interactions, or vocal fold oscillations without closure. Hitherto it has been impossible to visually analyze the vocal mechanism due to technical limitations. Latest high-speed technology, which captures 20 000 frames/s, using transnasal endoscopy was applied. Up to 1568Hz human vocal folds do exhibit oscillations with complete closure. Therefore, the recent results suggest that human voice production at very high F0s up to 1568Hz is not caused by turbulence, but rather by airflow modulation from vocal fold oscillations. (C) 2013 Acoustical Society of America

  • 18. Echternach, Matthias
    et al.
    Sundberg, Johan
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Baumann, Tobias
    Markl, Michael
    Richter, Bernhard
    Vocal tract area functions and formant frequencies in opera tenors' modal and falsetto registers2011Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 129, nr 6, s. 3955-3963Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    According to recent model investigations, vocal tract resonance is relevant to vocal registers. However, no experimental corroboration of this claim has been published so far. In the present investigation, ten professional tenors' vocal tract configurations were analyzed using MRI volumetry. All subjects produced a sustained tone on the pitch F4 (349 Hz) on the vowel /a/(1) in modal and (2) in falsetto register. The area functions were estimated from the MRI data and their associated formant frequencies were calculated. In a second condition the same subjects repeated the same tasks in a sound treated room and their formant frequencies were estimated by means of inverse filtering. In both recordings similar formant frequencies were observed. Vocal tract shapes differed between modal and falsetto register. In modal as compared to falsetto the lip opening and the oral cavity were wider and the first formant frequency was higher. In this sense the presented results are in agreement with the claim that the formant frequencies differ between registers.

  • 19.
    Elowsson, Anders
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH. Univ Oslo, RITMO Ctr Interdisciplinary Studies Rhythm Time &, Oslo, Norway..
    Polyphonic pitch tracking with deep layered learning2020Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 148, nr 1, s. 446-468Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article presents a polyphonic pitch tracking system that is able to extract both framewise and note-based estimates from audio. The system uses several artificial neural networks trained individually in a deep layered learning setup. First, cascading networks are applied to a spectrogram for framewise fundamental frequency (f(0)) estimation. A sparse receptive field is learned by the first network and then used as a filter kernel for parameter sharing throughout the system. Thef(0)activations are connected across time to extract pitch contours. These contours define a framework within which subsequent networks perform onset and offset detection, operating across both time and smaller pitch fluctuations at the same time. As input, the networks use, e.g., variations of latent representations from thef(0)estimation network. Finally, erroneous tentative notes are removed one by one in an iterative procedure that allows a network to classify notes within a correct context. The system was evaluated on four public test sets: MAPS, Bach10, TRIOS, and the MIREX Woodwind quintet and achieved state-of-the-art results for all four datasets. It performs well across all subtasksf(0), pitched onset, and pitched offset tracking.

  • 20.
    Elowsson, Anders
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Friberg, Anders
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Modeling the perception of tempo2015Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 137, nr 6, s. 3163-3177Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A system is proposed in which rhythmic representations are used to model the perception of tempo in music. The system can be understood as a five-layered model, where representations are transformed into higher-level abstractions in each layer. First, source separation is applied (Audio Level), onsets are detected (Onset Level), and interonset relationships are analyzed (Interonset Level). Then, several high-level representations of rhythm are computed (Rhythm Level). The periodicity of the music is modeled by the cepstroid vector-the periodicity of an interonset interval (IOI)-histogram. The pulse strength for plausible beat length candidates is defined by computing the magnitudes in different IOI histograms. The speed of the music is modeled as a continuous function on the basis of the idea that such a function corresponds to the underlying perceptual phenomena, and it seems to effectively reduce octave errors. By combining the rhythmic representations in a logistic regression framework, the tempo of the music is finally computed (Tempo Level). The results are the highest reported in a formal benchmarking test (2006-2013), with a P-Score of 0.857. Furthermore, the highest results so far are reported for two widely adopted test sets, with an Acc1 of 77.3% and 93.0% for the Songs and Ballroom datasets.

  • 21.
    Elowsson, Anders
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Friberg, Anders
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Predicting the perception of performed dynamics in music audio with ensemble learning2017Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 141, nr 3, s. 2224-2242Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    By varying the dynamics in a musical performance, the musician can convey structure and different expressions. Spectral properties of most musical instruments change in a complex way with the performed dynamics, but dedicated audio features for modeling the parameter are lacking. In this study, feature extraction methods were developed to capture relevant attributes related to spectral characteristics and spectral fluctuations, the latter through a sectional spectral flux. Previously, ground truths ratings of performed dynamics had been collected by asking listeners to rate how soft/loud the musicians played in a set of audio files. The ratings, averaged over subjects, were used to train three different machine learning models, using the audio features developed for the study as input. The highest result was produced from an ensemble of multilayer perceptrons with an R2 of 0.84. This result seems to be close to the upper bound, given the estimated uncertainty of the ground truth data. The result is well above that of individual human listeners of the previous listening experiment, and on par with the performance achieved from the average rating of six listeners. Features were analyzed with a factorial design, which highlighted the importance of source separation in the feature extraction.

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  • 22.
    Enflo, Bengt Olof
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Mekanik.
    Hedberg, C M
    Rudenko, O V
    Resonant properties of a nonlinear dissipative layer excited by a vibrating boundary: Q-factor and frequency response2005Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 117, nr 2, s. 601-612Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Simplified nonlinear evolution equations describing non-steady-state forced vibrations in an acoustic resonator having one closed end and the other end periodically oscillating are derived. An approach based on a nonlinear functional equation is used. The nonlinear Q-factor and the nonlinear frequency response of the resonator are calculated for steady-state oscillations of both inviscid and dissipative media. The general expression for the mean intensity of the acoustic wave in terms of the characteristic value of a Mathieu function is derived. The process of development of a standing wave is described analytically on the base of exact nonlinear solutions for different laws of periodic motion of the wall. For harmonic excitation the wave profiles are described by Mathieu functions, and their mean energy characteristics by the corresponding eigenvalues. The sawtooth-shaped motion of the boundary leads to a similar process of evolution of the profile, but the solution has a very simple form. Some possibilities to enhance the Q-factor of a nonlinear system by suppression of nonlinear energy losses are discussed.

  • 23.
    Fabiani, Marco
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Friberg, Anders
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Influence of pitch, loudness, and timbre on the perception of instrument dynamics2011Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 130, nr 4, s. EL193-EL199Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effect of variations in pitch, loudness, and timbre on the perception of the dynamics of isolated instrumental tones is investigated. A full factorial design was used in a listening experiment. The subjects were asked to indicate the perceived dynamics of each stimulus on a scale from pianissimo to fortissimo. Statistical analysis showed that for the instruments included (i.e., clarinet, flute, piano, trumpet, and violin) timbre and loudness had equally large effects, while pitch was relevant mostly for the first three. The results confirmed our hypothesis that loudness alone is not a reliable estimate of the dynamics of musical tones.

  • 24. Farooqui, Maaz
    et al.
    Elnady, Tamer
    Akl, Wael
    Sound attenuation in ducts using locally resonant periodic aluminum patches2016Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 139, nr 6, s. 3276-3286Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In recent years, the control of low frequency noise has received a lot of attention for several applications. Traditional passive noise control techniques using Helmholtz resonators have size limitations in the low frequency range because of the long wavelength. Promising noise reductions, with flush mounted aluminum patches with no size problems can be obtained using local resonance phenomenon implemented in acoustic metamaterial techniques. The objective of this work is to introduce locally resonant thin aluminum patches flush mounted to a duct walls aiming at creating frequency stop bands in a specific frequency range. Green's function is used within the framework of interface response theory to predict the amount of attenuation of the local resonant patches. The two-port theory and finite elements are also used to predict the acoustic performance of these patches. No flow measurements were conducted and show good agreement with the models. The effect of varying the damping and the masses of the patches are used to expand the stop bandwidth and the effect of both Bragg scattering and the locally resonant mechanisms was demonstrated using mathematical models. The effect of the arrays of patches on the effective dynamic density and bulk modulus has also been investigated.

  • 25. Farooqui, Maaz
    et al.
    Elnady, Tamer
    Akl, Wael
    Validation of low frequency noise attenuation using locally resonant patches2016Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Since conventional silencers in acoustic ducts have problems of size limitations at low frequencies and being prone to high backpressure, locally resonant aluminum patches are introduced in acoustic duct walls aiming at creating frequency stop bands in the low frequency region (below 1 KHz). With these flush mounted patches, promising noise reductions, with no such drawbacks, can be obtained, building on local resonance phenomenon implemented in acoustic metamaterials techniques. The objective of the current paper is to experimentally validate the performance of an array of flexible side-wall-mounted patches inside ducts. The experimental results are compared with Analytical Green's function method as well as Numerical Finite Element Method and a close agreement was found. The results show that the presence of the patches singly or periodically can play a prominent role in designing any acousticbandgap materials. The effect of the arrays of patches on the effective dynamic density and bulk modulushas also been investigated.

  • 26.
    Feng, Leiping
    et al.
    KTH, Tidigare Institutioner (före 2005), Farkostteknik.
    Liu, M. H.
    Nilsson, A.
    Experimental study of structure-borne sound transmission loss of mechanical joints2001Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 110, nr 3, s. 1391-1397Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A mechanical joint is one of the most effective ways to reduce the transmission of structure-borne sound. In order to increase the transmission loss, heavily damped joints are often used, which, in many cases, will reduce the structure integrity and hence can only be used in limited cases. In this study attention is focused on a type of resonant joint, i.e., a joint which will increase the transmission loss but will not reduce the structure integrity. The study is based on experiments in a one-dimensional structure. It is found that by adjusting the overlap of the joint, the transmission loss of 30 dB can be obtained at a certain frequency range without adding any dissipative materials. The mechanism of this high transmission loss is the cantilever-type resonance. The resonant frequency can be predicted precisely. The influence of extra dissipative material is investigated. The performance of the same joint in a finite structure is also examined by using the concept of vibrational insertion loss. When there is a certain damping in a finite system, a rather high insertion loss can still be achieved by using the above-mentioned joint, but the resonant frequency is shifted to higher end. It seems that the effective length of the cantilever is shortened by the finiteness.

  • 27.
    Feng, Leping
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Strukturakustik.
    Active control of structurally radiated sound using multi-actuator method1995Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 98, nr 1, s. 397-402Artikel i tidskrift (Refereegranskat)
  • 28.
    Feng, Leping
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Enhancement of low frequency sound absorption by placing thin plates on surface or between layers of porous materials2019Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 146, nr 2, s. EL141-EL144Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rigid thin plates can be used, either on the surface or between layers of materials, to improve the sound absorption properties of porous materials at low frequencies, especially for materials with low sound absorption. Measurement results obtained from a 100mm impedance tube, for different combinations of porous materials and thin plates, are supplied. Possible physical explanations are discussed. The size of the plate, together with the original properties of the porous material, determines the useful frequency region of the method. The technique of surface-placed thin plates can be directly applied to existing structures without making any changes of the original system, and the results are comparable to those with more complicated modifications.

  • 29.
    Finnveden, Svante
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Hörlin, Nils-Erik
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Barbagallo, Mathias
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Dynamic characterization of viscoelastic porous foams used in vehicles based on an inverse finite element method2014Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 135, nr 4, s. 1834-1843Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Viscoelastic properties of porous materials, typical of those used in vehicles for noise insulation and absorption, are estimated from measurements and inverse finite element procedures. The measurements are taken in a near vacuum and cover a broad frequency range: 20 Hz to 1 kHz. The almost cubic test samples were made of 25mm foam covered by a "heavy layer" of rubber. They were mounted in a vacuum chamber on an aluminum table, which was excited in the vertical and horizontal directions with a shaker. Three kinds of response are measured allowing complete estimates of the viscoelastic moduli for isotropic materials and also providing some information on the degree of material anisotropicity. First, frequency independent properties are estimated, where dissipation is described by constant loss factors. Then, fractional derivative models that capture the variation with frequency of the stiffness and damping are adapted. The measurement setup is essentially two-dimensional and calculations are three-dimensional and for a state of plane strain. The good agreement between measured and calculated response provides some confidence in the presented procedures. If, however, the material model cannot fit the measurements well, the inverse procedure yields a certain degree of arbitrariness to the parameter estimation.

  • 30.
    Friberg, Anders
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH.
    Lindeberg, Tony
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Beräkningsvetenskap och beräkningsteknik (CST).
    Hellwagner, Martin
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH.
    Helgason, Pétur
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH.
    Salomão, Gláucia Laís
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH.
    Elowsson, Anders
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH.
    Lemaitre, Guillaume
    Institute for Research and Coordination in Acoustics and Music, Paris, France.
    Ternström, Sten
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH.
    Prediction of three articulatory categories in vocal sound imitations using models for auditory receptive fields2018Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 144, nr 3, s. 1467-1483Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Vocal sound imitations provide a new challenge for understanding the coupling between articulatory mechanisms and the resulting audio. In this study, we have modeled the classification of three articulatory categories, phonation, supraglottal myoelastic vibrations, and turbulence from audio recordings. Two data sets were assembled, consisting of different vocal imitations by four professional imitators and four non-professional speakers in two different experiments. The audio data were manually annotated by two experienced phoneticians using a detailed articulatory description scheme. A separate set of audio features was developed specifically for each category using both time-domain and spectral methods. For all time-frequency transformations, and for some secondary processing, the recently developed Auditory Receptive Fields Toolbox was used. Three different machine learning methods were applied for predicting the final articulatory categories. The result with the best generalization was found using an ensemble of multilayer perceptrons. The cross-validated classification accuracy was 96.8 % for phonation, 90.8 % for supraglottal myoelastic vibrations, and 89.0 % for turbulence using all the 84 developed features. A final feature reduction to 22 features yielded similar results.

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  • 31.
    Friberg, Anders
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Schoonderwaldt, Erwin
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik. Hanover University, Germany .
    Hedblad, Anton
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Fabiani, Marco
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Elowsson, Anders
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Using listener-based perceptual features as intermediate representations in music information retrieval2014Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 136, nr 4, s. 1951-1963Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The notion of perceptual features is introduced for describing general music properties based on human perception. This is an attempt at rethinking the concept of features, aiming to approach the underlying human perception mechanisms. Instead of using concepts from music theory such as tones, pitches, and chords, a set of nine features describing overall properties of the music was selected. They were chosen from qualitative measures used in psychology studies and motivated from an ecological approach. The perceptual features were rated in two listening experiments using two different data sets. They were modeled both from symbolic and audio data using different sets of computational features. Ratings of emotional expression were predicted using the perceptual features. The results indicate that (1) at least some of the perceptual features are reliable estimates; (2) emotion ratings could be predicted by a small combination of perceptual features with an explained variance from 75% to 93% for the emotional dimensions activity and valence; (3) the perceptual features could only to a limited extent be modeled using existing audio features. Results clearly indicated that a small number of dedicated features were superior to a "brute force" model using a large number of general audio features.

  • 32.
    Friberg, Anders
    et al.
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    Sundberg, Johan
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    Does music performance allude to locomotion?: A model of final ritardandi derived from measurements of stopping runners1999Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 105, nr 3, s. 1469-1484Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This investigation explores the common assumption that music and motion are closely related by comparing the stopping of running and the termination of a piece of music. Video recordings were made of professional dancers’ stopping from running under different deceleration conditions, and instant values of body velocity, step frequency, and step length were estimated. In decelerations that were highly rated for aesthetic quality by a panel of choreographers, the mean body velocity could be approximated by a square-root function of time, which is equivalent to a cubic-root function of position. This implies a linear relationship between kinetic energy and time, i.e., a constant braking power. The mean body velocity showed a striking similarity with the mean tempo pattern of final ritardandi in music performances. The constant braking power was used as the basis for a model describing both the changes of tempo in final ritardandi and the changes of velocity in runners’ decelerations. The translation of physical motion to musical tempo was realized by assuming that velocity and musical tempo are equivalent. Two parameters were added to the model to account for the variation observed in individual ritardandi and in individual decelerations: ~1! the parameter q controlling the curvature, q53 corresponding to the runners’ deceleration, and ~2! the parameter vend for the final velocity and tempo value, respectively. A listening experiment was carried out presenting music examples with final ritardandi according to the model with different q values or to an alternative function. Highest ratings were obtained for the model with q52 and q53. Out of three functions, the model produced the best fit to individual measured ritardandi as well as to individual decelerations. A function previously used for modeling phrase-related tempo variations ~interonset duration as a quadratic function of score position! produced the lowest ratings and the poorest fits to individual ritardandi. The results thus seem to substantiate the commonly assumed analogies between motion and music.

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  • 33.
    Friberg, Anders
    et al.
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    Sundberg, Johan
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    Time discrimination in a monotonic, isochronous sequence1995Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, The Journal of the Acoustical Society of America, Vol. 5, nr 98, s. 2524-2531Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In acoustic communication timing seems to be an exceedingly important aspect. The just noticeable difference ~jnd! for small perturbations of an isochronous sequence of sounds is particularly important in music, in which such sequences frequently occur. This article reviews the literature in the area and presents an experiment designed to resolve some conflicting results in the literature regarding the tempo dependence for quick tempi and relevance of music experience. The jnd for a perturbation of the timing of a tone appearing in an isochronous sequence was examined by the method of adjustment. Thirty listeners of varied musical background were asked to adjust the position of the fourth tone in a sequence of six, such that they heard the sequence as perfectly isochronous. The tones were presented at a constant interonset time that was varied between 100 and 1000 ms. The absolute jnd was found to be approximately constant at 6 ms for tone interonset intervals shorter than about 240 ms and the relative jnd constant at 2.5% of the tone interonsets above 240 ms. Subjects’ musical training did not affect these values. Comparison with previous work showed that a constant absolute jnd below 250 ms and constant relative jnd above 250 ms tend to appear regardless of the perturbation type, at least if the sequence is relatively short.

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  • 34.
    Gaborit, Mathieu
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet. Le Mans Univ, Lab Acoust, CNRS, UMR 6613,Univ Mans, F-72000 Le Mans, France.
    Dazel, Olivier
    Le Mans Univ, Lab Acoust, CNRS, UMR 6613,Univ Mans, F-72000 Le Mans, France..
    Göransson, Peter
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    A simplified model for thin acoustic screens2018Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 144, nr 1, s. EL76-EL81Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A generalization of the commonly used pressure jump modeling of thin porous layers is proposed. The starting point is a transfer matrix model of the layer derived using matrix exponentials. First order expansions of the propagating terms lead to a linear approximation of the associated phenomena and the resulting matrix is further simplified based on physical assumptions. As a consequence, the equivalent fluid parameters used in the model may be reduced to simpler expressions and the transfer matrix rendered sparser. The proposed model is validated for different backing conditions, from normal to grazing incidence and for a wide range of thin films. In the paper, the physical hypotheses are discussed, together with the origin of the field jumps.

  • 35.
    Gaborit, Mathieu
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Dazel, Olivier
    LAUM UMR CNRS 6613, Le Mans Université, Le Mans, France.
    Göransson, Peter
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Erratum: A simplified model for thin acoustic screens [J. Acoust. Soc. Am. 144(1), EL76–EL81 (2018)]2019Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 146, nr 2, s. 1382-1383Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The present erratum reports an error impacting the figures of a contribution published in 2018 about a simplified model for thin acoustic screens in a transfer matrix context [Gaborit, Dazel, and Göransson (2018). J. Acoust. Soc. Am. 144(1), EL76–EL81]. A mistake in the implementation of the rigid termination condition for the systems under study is identified and a correct version is proposed along with the corrected figures. It is shown that this error does not impact the conclusions of the original contribution and that the model proposed therein keeps its advantages as the approximation error remains very similar to the previously reported values.

  • 36. Galembo, A.
    et al.
    Askenfelt, Anders
    KTH, Tidigare Institutioner (före 2005), Talöverföring och musikakustik.
    Cuddy, L. L.
    Russo, F. A.
    Effects of relative phases on pitch and timbre in the piano bass range2001Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 110, nr 3, s. 1649-1666Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Piano bass tones raise questions related to the perception of multicomponent, inharmonic tones. In this study, the influence of the relative phases among partials on pitch and timbre was investigated for synthesized bass tones with piano-like inharmonicity. Three sets of bass tones (A0 = 27.5 Hz, 100 partials, flat spectral envelope) were generated; harmonic, low inharmonic, and high inharmonic. For each set, five starting phase relations among partials were applied; sine phases, alternate (sine/cosine) phases, random phases, Schroeder phases, and negative Schroeder phases. The pitch and timbre of the tones were influenced markedly by the starting phases. Listening tests showed that listeners are able to discriminate between tones having different starting phase relations, and also that the pitch could be changed by manipulating the relative phases (octave, fifth, major third). A piano-like inharmonicity gives a characteristic randomizing effect of the phase relations over time in tones starting with nonrandom phase relations. A measure of the regularity of the phase differences between adjacent partials is suggested for quantifying this randomization process. The observed phase effects might be of importance in synthesizing, recording, and reproducing piano music.

  • 37. Goebl, W.
    et al.
    Bresin, Roberto
    KTH, Tidigare Institutioner (före 2005), Talöverföring och musikakustik.
    Measurement and reproduction accuracy of computer-controlled grand pianos2003Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 114, nr 4, s. 2273-2283Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The recording and reproducing capabilities of a Yamaha Disklavier grand piano and a Bosendorfer SE290 computer-controlled grand piano were tested, with the goal of examining their reliability for performance research. An experimental setup consisting of accelerometers and a calibrated microphone was used to capture key and hammer movements, as well as the acoustic signal. Five selected keys were played by pianists with two types of touch (staccato and legato). Timing and dynamic differences between the original performance, the corresponding MIDI file recorded by the computer-controlled pianos, and its reproduction were analyzed. The two devices performed quite differently with respect to timing and dynamic accuracy. The Disklavier's onset capturing was slightly more precise (+/-10 ms) than its reproduction (-20 to +30 ms); the Bosendorfer performed generally better, but its timing accuracy was slightly less precise for recording (-10 to 3 ms) than for reproduction (+/-2 ms). Both devices exhibited a systematic (linear) error in recording over time. In the dynamic dimension, the Bosendorfer showed higher consistency over the whole dynamic range, while the Disklavier performed well only in a wide middle range. Neither device was able to capture or reproduce different types of touch.

  • 38. Goebl, W.
    et al.
    Bresin, Roberto
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Galembo, A.
    Touch and temporal behavior of grand piano actions2005Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 118, nr 2, s. 1154-1165Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study investigated the temporal behavior of grand piano actions from different manufacturers under different touch conditions and dynamic levels. An experimental setup consisting of accelerometers and a calibrated microphone was used to capture key and hammer movements, as well as the sound signal. Five selected keys were played by pianists with two types of touch (pressed touch versus struck touch) over the entire dynamic range. Discrete measurements were extracted from the accelerometer data for each of the over 2300 recorded tones (e.g., finger-key, hammer-string, and key bottom contact times, maximum hammer velocity). Travel times of the hammer (from finger-key to hammer-string) as a function of maximum hammer velocity varied clearly between the two types of touch, but only slightly between pianos. A travel time approximation used in earlier work [Goebl W., (2001). J. Acoust. Soc. Am. 110, 563-572] derived from a computer-controlled piano was verified. Constant temporal behavior over type of touch and low compression properties of the parts of the action (reflected in key bottom contact times) were hypothesized to be indicators for instrumental quality.

  • 39. Goebl, Werner
    et al.
    Bresin, Roberto
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik. KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Fujinaga, Ichiro
    Perception of touch quality in piano tones2014Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 136, nr 5, s. 2839-2850Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Both timbre and dynamics of isolated piano tones are determined exclusively by the speed with which the hammer hits the strings. This physical view has been challenged by pianists who emphasize the importance of the way the keyboard is touched. This article presents empirical evidence from two perception experiments showing that touch-dependent sound components make sounds with identical hammer velocities but produced with different touch forms clearly distinguishable. The first experiment focused on finger-key sounds: musicians could identify pressed and struck touches. When the finger-key sounds were removed from the sounds, the effect vanished, suggest- ing that these sounds were the primary identification cue. The second experiment looked at key- keyframe sounds that occur when the key reaches key-bottom. Key-bottom impact was identified from key motion measured by a computer-controlled piano. Musicians were able to discriminate between piano tones that contain a key-bottom sound from those that do not. However, this effect might be attributable to sounds associated with the mechanical components of the piano action. In addition to the demonstrated acoustical effects of different touch forms, visual and tactile modalities may play important roles during piano performance that influence the production and perception of musical expression on the piano.

  • 40.
    Granqvist, Svante
    et al.
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    Hammarberg, Britta
    The correlogram: A visual display of periodicity2003Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 114, nr 5, s. 2934-2945Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fundamental frequency (F-0) extraction is often used in voice quality analysis'. In pathological voices with a high degree of instability in F-0, it is common for F-0 extraction algorithms to fail. In such cases, the faulty F-0 values might spoil the possibilities for further data analysis. This paper presents the correlogram, a new method of displaying periodicity. The correlogram is based on the waveform-matching techniques often used in F-0 extraction programs, but with no mechanism to select an actual F-0 value. Instead, several candidates for F-0 are shown as dark bands. The result is presented as a 3D plot with time on the x axis, correlation delay inverted to frequency on the y axis, and correlation on the z axis. The z axis is represented in a gray scale as in a spectrogram. Delays corresponding to integer multiples, of the period time will receive high correlation, thus resulting in candidates at F-0, F-0/2, F-0/3, etc. While the correlogram, adds little to F-0 analysis of normal voices, it is useful for analysis of pathological voices since it illustrates the full. complexity of the periodicity in the voice signal. Also, in combination with manual tracing, the correlogram can be used for semimanual F-0 extraction. If so, F-0 extraction can be performed on many voices that cause problems for conventional F-0 extractors. To demonstrate the properties of the method it is applied to synthetic and natural voices, among them six pathological voices, which are characterized by roughness, vocal fry, gratings/scrape, hypofunctional breathiness and voice breaks, or combinations of these.

  • 41.
    Granqvist, Svante
    et al.
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    Lindestad, Per-Åke
    A method of applying Fourier analysis to high-speed laryngoscopy2001Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 110, nr 6, s. 3193-3197Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new method for analysis of digital high-speed recordings of vocal-fold vibrations is presented. The method is based on the extraction of light-intensity time sequences from consecutive images, which in turn are Fourier transformed. The spectra thus acquired can be displayed in four different modes, each having its own benefits. When applied to the larynx, the method visualizes oscillations in the entire laryngeal area, not merely the glottal region. The method was applied to two laryngoscopic high-speed image sequences. Among these examples, covibrations in the ventricular folds and in the mucosa covering the arytenoid cartilages were found. In some cases the covibrations occurred at other frequencies than those of the glottis.

  • 42.
    Granqvist, Svante
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Tal-kommunikation.
    Sundberg, Johan
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Lundberg, J. O.
    Weitzberg, E.
    Paranasal sinus ventilation by humming2006Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 119, nr 5, s. 2611-2617Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The gas nitric oxide (NO) is generated in the human paranasal sinuses and can be measured in nasally exhaled air. During humming, a marked increase in exhaled NO content has been observed. The acoustic phenomenon responsible for this evacuation of NO gas from the sinuses was analyzed. A tube model was constructed with a syringe containing NO gas attached radially. This tube was excited with an air stream modulated by a sine wave. Increased evacuation was observed whenever the syringe was not located at a pressure node of the exciting sine wave. A computer model of the system showed a good matching of observed pressure versus frequency data in the syringe resonator. The results thus suggest that the alternating pressure in the nasal cavity forces the air plug in the ostium of the paranasal sinus resonators to vibrate, thus expelling from the cavity NO gas, which is transported to free air by the exhalatory air stream.

  • 43.
    Grell, Anke
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Sundberg, Johan
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Ternström, Sten
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Ptok, Martin
    Altenmueller, Eckart
    Rapid pitch correction in choir singers2009Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 126, nr 1, s. 407-413Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Highly and moderately skilled choral singers listened to a perfect fifth reference, with the instruction to complement the fifth such that a major triad resulted. The fifth was suddenly and unexpectedly shifted in pitch, and the singers' task was to shift the fundamental frequency of the sung tone accordingly. The F0 curves during the transitions often showed two phases, an initial quick and large change followed by a slower and smaller change, apparently intended to fine-tune voice F0 to complement the fifth. Anesthetizing the vocal folds of moderately skilled singers tended to delay the reaction. The means of the response times varied in the range 197- 259 ms depending on direction and size of the pitch shifts, as well as on skill and anesthetization.

  • 44.
    Gudmarsson, Anders
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Ryden, N.
    Birgisson, Björn
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Application of Resonant Acoustic Spectoscopy to Beam Shaped Asphalt Concrete Samples2010Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 128, nr 4, s. 2453-2453Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The dynamic modulus of asphalt concrete is a key parameter needed in modern pavement design and management. Traditional laboratory tests based on cyclic loading (0.1–25 Hz) at different testing temperatures are time consuming and require expensive equipment. There is therefore a need for more efficient non‐destructive methods to determine the dynamic modulus of asphalt concrete. This study applies resonant acoustic spectroscopy (RAS) to beam shaped asphalt concrete samples. Multiple modes of vibration are measured at each testing temperature using a miniature accelerometer and a small steel sphere as impact source. The complex modulus from each resonant frequency is calculated using the Rayleigh–Ritz method. The heterogeneous and viscoelastic nature of asphalt concrete presents challenges to the application of conventional RAS. The number of measurable modes decreases with increasing test temperature. In an attempt to extend the usable frequency and temperature range measured, transfer functions are inverted using the finite element method along with a frequency dependent complex modulus. Initial results indicate that RAS can be an efficient method for the prediction of the high‐frequency part of the asphalt concrete dynamic modulus mastercurve.

  • 45.
    Gudmarsson, Anders
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Rydén, Nils
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Birgisson, Björn
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Väg- och banteknik.
    Characterizing the low strain complex modulus of asphalt concrete specimens through optimization of frequency response functions2012Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 132, nr 4, s. 2304-2312Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Measured and finite element simulated frequency response functions are used to characterize the low strain (similar to 10(-7)) complex moduli of an asphalt concrete specimen. The frequency response functions of the specimen are measured at different temperatures by using an instrumented hammer to apply a load and an accelerometer to measure the dynamic response. Theoretical frequency response functions are determined by modeling the specimen as a three-dimensional (3D) linear isotropic viscoelastic material in a finite element program. The complex moduli are characterized by optimizing the theoretical frequency response functions against the measured ones. The method is shown to provide a good fit between the frequency response functions, giving an estimation of the complex modulus between minimum 500 Hz and maximum 18 vertical bar 000 Hz depending on the temperature. Furthermore, the optimization method is shown to give a good estimation of the complex modulus master curve.

  • 46. Guettler, K.
    et al.
    Askenfelt, Anders
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Musikakustik.
    Buen, A.
    Double basses on the stage floor: Tuning fork–table top effect or not?2012Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 131, nr 1, s. 795-806Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The question whether or not double basses can benefit from a compliant and radiating stage floor in the low end of their tonal register, similar to the well-known tuning fork–tabletop effect, was examined through field experiments in five concert halls. The topic comprises several aspects: (1) How well the mechanical impedances of double basses and the stage floor match, (2) amount of vibration velocity transmitted to the floor through the end pin of the bass, and (3) radiation efficiency of point-excited bending waves in the stage floor far below the coincidence frequency. Each aspect represents a prerequisite for the tuning fork–tabletop effect to take place. The input impedance at the end pin was measured for three representative double basses. The stage floors of five orchestra halls were measured with respect input impedance and damping, while sound radiation to the audience area was measured for two of them. In Lindeman Hall, Oslo, all conditions for the tuning fork–tabletop effect to take place were clearly met. The contribution from the stage-floor radiation to the sound pressure level in the audience area was found to be about 5 dB between 40 and 60 Hz, and even higher between 30 and 40 Hz.

  • 47. Gustafsson, M.
    et al.
    He, Sailing
    KTH, Tidigare Institutioner (före 2005), Teoretisk elektroteknik.
    An optimization approach to multi-dimensional time domain acoustic inverse problems2000Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 108, nr 4, s. 1548-1556Artikel i tidskrift (Refereegranskat)
  • 48.
    Hammarström, Björn
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik. KTH Royal Inst Technol, Dept Appl Phys, Roslagstullsbacken 21, SE-11421 Stockholm, Sweden..
    Skov, Nils R.
    Tech Univ Denmark, Dept Phys, DTU Phys Bldg 309, DK-2800 Lyngby, Denmark..
    Olofsson, Karl
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik. KTH Royal Inst Technol, Dept Appl Phys, Roslagstullsbacken 21, SE-11421 Stockholm, Sweden..
    Bruus, Henrik
    Tech Univ Denmark, Dept Phys, DTU Phys Bldg 309, DK-2800 Lyngby, Denmark..
    Wiklund, Martin
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik. KTH Royal Inst Technol, Dept Appl Phys, Roslagstullsbacken 21, SE-11421 Stockholm, Sweden..
    Acoustic trapping based on surface displacement of resonance modes2021Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 149, nr 3, s. 1445-1453Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Acoustic trapping is a promising technique for aligning particles in two-dimensional arrays, as well as for dynamic manipulation of particles individually or in groups. The actuating principles used in current systems rely on either cavity modes in enclosures or complex arrangements for phase control. Therefore, available systems either require high power inputs and costly peripheral equipment or sacrifice flexibility. This work presents a different concept for acoustic trapping of particles and cells that enables dynamically defined trapping patterns inside a simple and inexpensive setup. Here, dynamic operation and dexterous trapping are realized through the use of a modified piezoelectric transducer in direct contact with the liquid sample. Physical modeling shows how the transducer induces an acoustic force potential where the conventional trapping in the axial direction is supplemented by surface displacement dependent lateral trapping. The lateral field is a horizontal array of pronounced potential minima with frequency-dependent locations. The resulting system enables dynamic arraying of levitated trapping sites at low power and can be manufactured at ultra-low cost, operated using low-cost electronics, and assembled in less than 5 min. We demonstrate dynamic patterning of particles and biological cells and exemplify potential uses of the technique for cell-based sample preparation and cell culture.

  • 49.
    Heldner, Mattias
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH, Tal-kommunikation.
    Detection thresholds for gaps, overlaps, and no-gap-no-overlaps2011Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 130, nr 1, s. 508-513Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Detection thresholds for gaps and overlaps, that is acoustic and perceived silences and stretches of overlapping speech in speaker changes, were determined. Subliminal gaps and overlaps were categorized as no-gap-no-overlaps. The established gap and overlap detection thresholds both corresponded to the duration of a long vowel, or about 120 ms. These detection thresholds are valuable for mapping the perceptual speaker change categories gaps, overlaps, and no-gap-no-overlaps into the acoustic domain. Furthermore, the detection thresholds allow generation and understanding of gaps, overlaps, and no-gap-no-overlaps in human-like spoken dialogue systems.

  • 50. Heo, Yong-Ho
    et al.
    Ih, Jeong-Guon
    Bodén, Hans
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, MWL Marcus Wallenberg Laboratoriet.
    Acoustic source identification of an axial fan in a duct considering the rotation effect2016Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 140, nr 1, s. 145-156Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For developing the quiet axial fans, the spatial distribution of acoustic source parameters over the source plane provides essential information. In this study, the previously suggested source identification technique by authors is newly applied to an axial fan. To obtain the acoustic source parameters in a duct, one should overcome many technical difficulties related with: the turbulent flow, high order modes, rotating sources, inverse estimation. Measurements are conducted with several arrays of flush mounted microphones deployed on the periphery of the duct wall. A reference trigger signal obtained from the rotating blade is used to suppress the effect of turbulent flow in the measured pressure spectra with a reduction of about 25 dB in the present work. The maximum error between measurement and estimation is generally <-20 dB in the measurement plane in the very vicinity to the source. The visualized source images clearly indicate the locations and the strengths of main contributors to the radiated sound, e.g., for the inlet of the axial fan, the tip clearance between fan blades and shroud wall.

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