Julius Smith

All Publications

• Electric-to-acoustic pickup processing for string instruments: An experimental study of the guitar with a hexaphonic pickupa) JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA Rau, M., Abel, J. S., James, D., Smith, J. O. 2021; 150 (1): 385-397

  View details for DOI 10.1121/10.0005540

  View details for Web of Science ID 000675403200001

• State-space modeling of sound source directivity: An experimental study of the violin and the clarinet. The Journal of the Acoustical Society of America Maestre, E., Scavone, G. P., Smith, J. O. 2021; 149 (4): 2768

  Abstract

  A method is presented for simulating the free-field, frequency-dependent directivity of linear sound sources for use in real-time within geometric acoustic environments. The method, which is applied to modeling the directivity of a violin body and a clarinet air column from experimental acoustic data in this study, is based on using minimum-phase measurements to design a state-space filter, allowing the interactive simulation of a time-varying number of radiated sound wavefronts, each toward a time-varying direction. With applicability in sound synthesis and/or auralization within virtual environments, where sound sources change position and orientation dynamically, techniques are proposed for modeling and simulating directivity profiles on perceptual frequency axes with alternatives for representing directivity on a per-vibration-mode basis while incorporating relative phase terms or by reduced-order efficient representations comprising separate components for the signature resonant structure and the associated directivity on an adjustable frequency resolution.

  View details for DOI 10.1121/10.0004241

  View details for PubMedID 33940861

• Improved Real-Time Monophonic Pitch Tracking with the Extended Complex Kalman Filter JOURNAL OF THE AUDIO ENGINEERING SOCIETY Das, O., Smith, J. O., Chafe, C. 2020; 68 (1-2): 78–86

  View details for DOI 10.17743/jaes.2019.0053

  View details for Web of Science ID 000607787600008

• Converting Series Biquad Filters Into Delayed Parallel Form: Application to Graphic Equalizers IEEE TRANSACTIONS ON SIGNAL PROCESSING Liski, J., Bank, B., Smith, J. O., Valimaki, V. 2019; 67 (14): 3785–95

  View details for DOI 10.1109/TSP.2019.2919419

  View details for Web of Science ID 000472607600002

• Generalized Wave Digital Filter Realizations of Arbitrary Reciprocal Connection Networks IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS Bernardim, A., Werner, K., Smith, J., Sarti, A. 2019; 66 (2): 694–707

  View details for DOI 10.1109/TCSI.2018.2867508

  View details for Web of Science ID 000457357200021

• Modeling Circuits With Arbitrary Topologies and Active Linear Multiports Using Wave Digital Filters IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS Werner, K., Bernardini, A., Smith, J. O., Sarti, A. 2018; 65 (12): 4233–46

  View details for DOI 10.1109/TCSI.2018.2837912

  View details for Web of Science ID 000448934700017

• Modeling sound scattering using a combination of the edge source integral equation and the boundary element method. The Journal of the Acoustical Society of America Martin, S. R., Svensson, U. P., Slechta, J., Smith, J. O. 2018; 144 (1): 131

  Abstract

  A hybrid method for sound scattering calculations is presented in this paper. The boundary element method (BEM) is combined with a recently developed edge source integral equation (ESIE) [J. Acoust. Soc. Am. 133, 3681-3691 (2013)]. Although the ESIE provides accurate results for convex, rigid polyhedra, it has several numerical challenges, one of which applies to certain radiation directions. The proposed method, denoted ESIEBEM, overcomes this problem with certain radiation directions by applying a similar approach as BEM. First, the sound pressure is calculated on the surface of the scattering object using the ESIE, and then second, the scattered sound is obtained at the receiver point using the Kirchhoff-Helmholtz boundary integral equation, as BEM does. The three methods have been compared for the scattering by a rigid cube. Based on results from several discretizations, ESIE and ESIEBEM results are typically (90% quartile) within 3-4·10-4 for a kL-value of 1.83 and 2·10-3 for kL=9.15, L being the cube length, of reference results computed with the BEM. The computational cost of ESIEBEM appears to be lower than BEM.

  View details for PubMedID 30075636

• Modeling sound scattering using a combination of the edge source integral equation and the boundary element method JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA Martin, S. R., Svensson, U., Slechta, J., Smith, J. O. 2018; 144 (1): 131-141

  View details for DOI 10.1121/1.5044404

  View details for Web of Science ID 000440810900027

• Mobile Music, Sensors, Physical Modeling, and Digital Fabrication: Articulating the Augmented Mobile Instrument APPLIED SCIENCES-BASEL Michon, R., Smith, J., Wright, M., Chafe, C., Granzow, J., Wang, G. 2017; 7 (12)

  View details for DOI 10.3390/app7121311

  View details for Web of Science ID 000419175800107

• Perceptual Spatial Audio Recording, Simulation, and Rendering IEEE SIGNAL PROCESSING MAGAZINE Hacihabiboglu, H., De Sena, E., Cvetkovic, Z., Johnston, J., Smith, J. O. 2017; 34 (3): 36-54

  View details for DOI 10.1109/MSP.2017.2666081

  View details for Web of Science ID 000400377100007

• Joint Modeling of Bridge Admittance and Body Radiativity for Efficient Synthesis of String Instrument Sound by Digital Waveguides IEEE-ACM TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING Maestre, E., Scavone, G. P., Smith, J. O. 2017; 25 (5): 1128-1139

  View details for DOI 10.1109/TASLP.2017.2689241

  View details for Web of Science ID 000410513000004

• Design of Recursive Digital Filters in Parallel Form by Linearly Constrained Pole Optimization IEEE SIGNAL PROCESSING LETTERS Maestre, E., Scavone, G. P., Smith, J. O. 2016; 23 (11): 1547-1550

  View details for DOI 10.1109/LSP.2016.2605626

  View details for Web of Science ID 000384589300001

• Modeling Nonlinear Wave Digital Elements Using the Lambert Function IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS Bernardini, A., Werner, K. J., Sarti, A., Smith, J. O. 2016; 63 (8): 1231-1242

  View details for DOI 10.1109/TCSI.2016.2573119

  View details for Web of Science ID 000383596000013

• More Than Fifty Years of Artificial Reverberation Valimaki, V., Parker, J. D., Savioja, L., Smith, J. O., Abel, J. S., Goetze, S., Spriet, A. AUDIO ENGINEERING SOC INC. 2016

  View details for Web of Science ID 000576926400001

• Wave Digital Filter Modeling of Circuits with Operational Amplifiers Werner, K., Dunkel, W., Rest, M., Olsen, M., Smith, J. O., IEEE IEEE. 2016: 1033-1037

  View details for Web of Science ID 000391891900198

• RESOLVING GROUPED NONLINEARITIES IN WAVE DIGITAL FILTERS USING ITERATIVE TECHNIQUES Olsen, M., Werner, K., Smith, J. O., Rajmic, P., Rund, F., Schimmel, J. BRNO UNIV TECHNOLOGY, FAC ELECTRICAL ENG & COMMUNICATION. 2016: 279-286

  View details for Web of Science ID 000432607600039

• THE FENDER BASSMAN 5F6-A FAMILY OF PREAMPLIFIER CIRCUITS-A WAVE DIGITAL FILTER CASE STUDY Dunkel, W., Rest, M., Werner, K., Olsen, M., Smith, J. O., Rajmic, P., Rund, F., Schimmel, J. BRNO UNIV TECHNOLOGY, FAC ELECTRICAL ENG & COMMUNICATION. 2016: 263-270

  View details for Web of Science ID 000432607600037

• RT-WDF-A MODULAR WAVE DIGITAL FILTER LIBRARY WITH SUPPORT FOR ARBITRARY TOPOLOGIES AND MULTIPLE NONLINEARITIES Rest, M., Dunkel, W., Werner, K., Smith, J. O., Rajmic, P., Rund, F., Schimmel, J. BRNO UNIV TECHNOLOGY, FAC ELECTRICAL ENG & COMMUNICATION. 2016: 287-294

  View details for Web of Science ID 000432607600040

• SYNTHESIS OF SOUND TEXTURES WITH TONAL COMPONENTS USING SUMMARY STATISTICS AND ALL-POLE RESIDUAL MODELING Kim, H., Smith, J., Rajmic, P., Rund, F., Schimmel, J. BRNO UNIV TECHNOLOGY, FAC ELECTRICAL ENG & COMMUNICATION. 2016: 129-136

  View details for Web of Science ID 000432607600019

• Efficient Synthesis of Room Acoustics via Scattering Delay Networks IEEE-ACM TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING De Sena, E., Hacihabiboglu, H., Cvetkovic, Z., Smith, J. O. 2015; 23 (9): 1478-1492

  View details for DOI 10.1109/TASLP.2015.2438547

  View details for Web of Science ID 000356006900007

• WAVE DIGITAL FILTER ADAPTORS FOR ARBITRARY TOPOLOGIES AND MULTIPORT LINEAR ELEMENTS Werner, K., Smith, J. O., Abel, J. S., Svensson, P., Kristiansen, U. NORWEGIAN UNIV SCI TECHNOL. 2015: 379–86

  View details for Web of Science ID 000432610400056

• DIGITAL MODELING OF STRING INSTRUMENT BRIDGE REFLECTANCE AND BODY RADIATIVITY FOR SOUND SYNTHESIS BY DIGITAL WAVEGUIDES Maestre, E., Scavone, G. P., Smith, J. O., IEEE IEEE. 2015

  View details for Web of Science ID 000377205500069

• An Energetic Interpretation of Nonlinear Wave Digital Filter Lookup Table Error Werner, K., Smith, J. O., IEEE IEEE. 2015

  View details for Web of Science ID 000380451600067

• HARMONIZING EFFECT USING SHORT-TIME TIME-REVERSAL Kim, H., Smith, J. O., Svensson, P., Kristiansen, U. NORWEGIAN UNIV SCI TECHNOL. 2015: 81-86

  View details for Web of Science ID 000432610400012

• Multi-Port NonLinearities in Wave Digital Structures Bernardini, A., Werner, K. J., Sarti, A., Smith, J. O., IEEE IEEE. 2015

  View details for Web of Science ID 000380451600069

• A GENERAL AND EXPLICIT FORMULATION FOR WAVE DIGITAL FILTERS WITH MULTIPLE/MULTIPORT NONLINEARITIES AND COMPLICATED TOPOLOGIES Werner, K., Nangia, V., Smith, J. O., Abel, J. S., IEEE IEEE. 2015

  View details for Web of Science ID 000377205500026

• RESOLVING WAVE DIGITAL FILTERS WITH MULTIPLE/MULTIPORT NONLINEARITIES Werner, K., Nangia, V., Smith, J. O., Abel, J. S., Svensson, P., Kristiansen, U. NORWEGIAN UNIV SCI TECHNOL. 2015: 387–94

  View details for Web of Science ID 000432610400057

• A PHYSICALLY-INFORMED, CIRCUIT-BENDABLE, DIGITAL MODEL OF THE ROLAND TR-808 BASS DRUM CIRCUIT Werner, K., Abel, J. S., Smith, J. O., Int Audio Labs Erlangen INT AUDIO LABORATORIES ERLANGEN. 2014: 159–66

  View details for Web of Science ID 000432613600023

• SHORT-TIME TIME-REVERSAL ON AUDIO SIGNALS Kim, H., Smith, J. O., Int Audio Labs Erlangen INT AUDIO LABORATORIES ERLANGEN. 2014: 29-33

  View details for Web of Science ID 000432613600005

• Towards a physical model of the berimbau: Obtaining the modal synthesis of the cabaza. journal of the Acoustical Society of America Castellanos Macin, P., Smith, J. O. 2013; 134 (5): 4243-?

  Abstract

  The worldwide presence of Brazilian culture grows every day. However, some of the musical instruments used in its principal cultural activities lack of a formal acoustic analysis which would make them more understandable for the rest of the world. One of them is the berimbau-de-barriga (berimbau), which consists of a string (wire) attached to an arched rod and a resonance box called cabaza. Modeling the berimbau will not only open up possibilities for its application to other musical genres, but will also allow the incorporation of its characteristics into new virtual instruments. The present work describes the modal synthesis of the cabaza, i.e., modeling this sounding box as a parallel bank of digital resonators. Impulse response measurements were obtained using a force hammer, and second-order resonator frequency-responses were fit to the data using Matlab.

  View details for DOI 10.1121/1.4831602

  View details for PubMedID 24181934

• Force-Sensitive Detents Improve User Performance for Linear Selection Tasks IEEE TRANSACTIONS ON HAPTICS Berdahl, E., Smith, J. O., Weinzierl, S., Niemeyer, G. 2013; 6 (2): 206-216

  Abstract

  Haptic technology, providing force cues and creating a programmable interface, can assist users in more accurately using an interface. This paper investigates haptic assistance in combination with auditory feedback instead of visual feedback. A user test is carried out in which participants select fundamental frequencies from a continuous range to play brief musical melodies. Two control conditions are compared with two detent-based haptic assistance conditions. The detents gently guide the users toward locations of equal tempered fundamental frequencies. Results from the user test confirm improved accuracy brought about by the detents. It is further helpful to provide regulation of the strength of haptic assistance in real time, allowing the user to remain always in control. This concept motivated the force-sensitive detent condition, which enables the user to adjust the strength of the haptic assistance in real time by changing the downward force applied to the haptic device. The work implies that users of graphical user interfaces could similarly benefit from force-sensitive detents and more generally real-time regulation of the strength of haptic assistance.

  View details for DOI 10.1109/ToH.2012.55

  View details for Web of Science ID 000319877500007

• Fifty Years of Artificial Reverberation IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING Valimaki, V., Parker, J. D., Savioja, L., Smith, J. O., Abel, J. S. 2012; 20 (5): 1421-1448

  View details for DOI 10.1109/TASL.2012.2189567

  View details for Web of Science ID 000302210400001

• Optimized Polynomial Spline Basis Function Design for Quasi-Bandlimited Classical Waveform Synthesis IEEE SIGNAL PROCESSING LETTERS Pekonen, J., Juhan Nam, J., Smith, J. O., Valimaki, V. 2012; 19 (3): 159-162

  View details for DOI 10.1109/LSP.2012.2183123

  View details for Web of Science ID 000299811300001

• EXPLOITING THE HARMONIC STRUCTURE FOR SPEECH ENHANCEMENT IEEE International Conference on Acoustics, Speech and Signal Processing Cho, E., Smith, J. O., Widrow, B. IEEE. 2012: 4569–4572

  View details for Web of Science ID 000312381404160

• Feedback control of acoustic musical instruments: Collocated control using physical analogs JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA Berdahl, E., Smith, J. O., Niemeyer, G. 2012; 131 (1): 963-973

  Abstract

  Traditionally, the average professional musician has owned numerous acoustic musical instruments, many of them having distinctive acoustic qualities. However, a modern musician could prefer to have a single musical instrument whose acoustics are programmable by feedback control, where acoustic variables are estimated from sensor measurements in real time and then fed back in order to influence the controlled variables. In this paper, theory is presented that describes stable feedback control of an acoustic musical instrument. The presentation should be accessible to members of the musical acoustics community who may have limited or no experience with feedback control. First, the only control strategy guaranteed to be stable subject to any musical instrument mobility is described: the sensors and actuators must be collocated, and the controller must emulate a physical analog system. Next, the most fundamental feedback controllers and the corresponding physical analog systems are presented. The effects that these controllers have on acoustic musical instruments are described. Finally, practical design challenges are discussed. A proof explains why changing the resonance frequency of a musical resonance requires much more control power than changing the decay time of the resonance.

  View details for DOI 10.1121/1.3651091

  View details for Web of Science ID 000299131200032

  View details for PubMedID 22280719

• Audio Signal Processing Using Graphics Processing Units JOURNAL OF THE AUDIO ENGINEERING SOCIETY Savioja, L., Valimaki, V., Smith, J. O. 2011; 59 (1-2): 3-19

  View details for Web of Science ID 000288572800001

• Analysis and Synthesis of Coupled Vibrating Strings Using a Hybrid Modal-Waveguide Synthesis Model IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING Lee, N., Smith, J. O., Valimaki, V. 2010; 18 (4): 833-842

  View details for DOI 10.1109/TASL.2009.2033979

  View details for Web of Science ID 000276621600012

• Introduction to the Special Issue on Virtual Analog Audio Effects and Musical Instruments IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING Valimaki, V., Fontana, F., Smith, J. O., Zoelzer, U. 2010; 18 (4): 713-714

  View details for DOI 10.1109/TASL.2010.2046449

  View details for Web of Science ID 000276621600001

• Automated Physical Modeling of Nonlinear Audio Circuits For Real-Time Audio Effects-Part I: Theoretical Development IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING Yeh, D. T., Abel, J. S., Smith, J. O. 2010; 18 (4): 728-737

  View details for DOI 10.1109/TASL.2009.2033978

  View details for Web of Science ID 000276621600003

• Alias-Suppressed Oscillators Based on Differentiated Polynomial Waveforms IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING Valimaki, V., Nam, J., Smith, J. O., Abel, J. S. 2010; 18 (4): 786-798

  View details for DOI 10.1109/TASL.2009.2026507

  View details for Web of Science ID 000276621600008

• Efficient Antialiasing Oscillator Algorithms Using Low-Order Fractional Delay Filters IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING Nam, J., Valimaki, V., Abel, J. S., Smith, J. O. 2010; 18 (4): 773-785

  View details for DOI 10.1109/TASL.2009.2035039

  View details for Web of Science ID 000276621600007

• Robust, Efficient Design of Allpass Filters for Dispersive String Sound Synthesis IEEE SIGNAL PROCESSING LETTERS Abel, J. S., Valimaki, V., Smith, J. O. 2010; 17 (4): 406–9

  View details for DOI 10.1109/LSP.2010.2040924

  View details for Web of Science ID 000417800000001

• Virtual String Synthesis SCIENCE OF STRING INSTRUMENTS Lee, N., Smith, J. O., Rossing, T. D. 2010: 417-455

  View details for DOI 10.1007/978-1-4419-7110-4_23

  View details for Web of Science ID 000286092900023

• Spectral Delay Filters JOURNAL OF THE AUDIO ENGINEERING SOCIETY Valimaki, V., Abel, J. S., Smith, J. O. 2009; 57 (7-8): 521-531

  View details for Web of Science ID 000269367300004

• Numerical methods for simulation of guitar distortion circuits COMPUTER MUSIC JOURNAL Yeh, D. T., Abei, J. S., Vladimirescu, A., Smith, J. O. 2008; 32 (2): 23-42

  View details for Web of Science ID 000256805700002

• Audio Watermarking through Deterministic plus Stochastic Signal Decomposition EURASIP JOURNAL ON INFORMATION SECURITY Liu, Y., Smith, J. O. 2007

  View details for DOI 10.1155/2007/75961

  View details for Web of Science ID 000215280000005

• Parameterized finite difference schemes for plates: Stability, the reduction of directional dispersion and frequency warping IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING Bilbao, S., Savioja, L., Smith, J. O. 2007; 15 (4): 1488-1495

  View details for DOI 10.1109/TASL.2006.889737

  View details for Web of Science ID 000245909800032

• Generative model of voice in noise for structured coding applications 32nd IEEE International Conference on Acoustics, Speech and Signal Processing Jinachitra, P., Smith, J. O. IEEE. 2007: 281–284

  View details for Web of Science ID 000249040000071

• Humming Control Interface for Hand-held Devices 9th International ACM SIGACCESS Conference on Computers and Accessibility Won, S. Y., Lee, D., Smith, J. ASSOC COMPUTING MACHINERY. 2007: 259–260

  View details for Web of Science ID 000268617200049

• Efficient time-varying loudness estimation via the hopping Goertzel DFT 50th Midwest Symposium on Circuits and Systems Cassidy, R. J., Smith, J. O. IEEE. 2007: 362–363

  View details for Web of Science ID 000257110900092

• Inducing unusual dynamics in acoustic musical instruments IEEE Conference on Control Applications Berdahl, E., Smith, J. O. IEEE. 2007: 411–416

  View details for Web of Science ID 000253024000070

• Singer-dependent falsetto detection for live vocal processing based on support vector classification 40th Asilomar Conference on Signals, Systems and Computers Mysore, G. J., Cassidy, R. J., Smith, J. O. IEEE. 2006: 1139–1142

  View details for Web of Science ID 000246925202054

• Energy-conserving finite difference schemes for nonlinear strings ACTA ACUSTICA UNITED WITH ACUSTICA Bilbao, S., Smith, J. O. 2005; 91 (2): 299-311

  View details for Web of Science ID 000228392800012

• Joint estimation of glottal source and vocal tract for vocal synthesis using Kalman smoothing and EM algorithm Workshop on Applications of Sigbak Processing to Audio and Acoustics Jinachitra, P., Smith, J. O. IEEE. 2005: 327–330

  View details for Web of Science ID 000236204100082

• The simulation of piano string vibration: From physical models to finite difference schemes and digital waveguides JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA Bensa, J., Bilbao, S., Kronland-Martinet, R., Smith, J. O. 2003; 114 (2): 1095-1107

  Abstract

  A model of transverse piano string vibration, second order in time, which models frequency-dependent loss and dispersion effects is presented here. This model has many desirable properties, in particular that it can be written as a well-posed initial-boundary value problem (permitting stable finite difference schemes) and that it may be directly related to a digital waveguide model, a digital filter-based algorithm which can be used for musical sound synthesis. Techniques for the extraction of model parameters from experimental data over the full range of the grand piano are discussed, as is the link between the model parameters and the filter responses in a digital waveguide. Simulations are performed. Finally, the waveguide model is extended to the case of several coupled strings.

  View details for DOI 10.1121/1.1587146

  View details for Web of Science ID 000184637500048

  View details for PubMedID 12942987

• Finite difference schemes and digital waveguide networks for the wave equation: Stability, passivity, and numerical dispersion IEEE TRANSACTIONS ON SPEECH AND AUDIO PROCESSING Bilbao, S., Smith, J. O. 2003; 11 (3): 255-266

  View details for DOI 10.1109/TSA.2003.811535

  View details for Web of Science ID 000183877300009

• PHYSICAL MODELING USING DIGITAL WAVE-GUIDES COMPUTER MUSIC JOURNAL Smith, J. O. 1992; 16 (4): 74-98

  View details for Web of Science ID A1992KH76800010

• SMITH,J.O. COMMENTS ON SULLIVAN KARPLUS-STRONG ARTICLE COMPUTER MUSIC JOURNAL Smith, J. O. 1991; 15 (2): 10-11

  View details for Web of Science ID A1991FP42600005

• FUNDAMENTALS OF DIGITAL-FILTER THEORY COMPUTER MUSIC JOURNAL Smith, J. O. 1985; 9 (3): 13-23

  View details for Web of Science ID A1985ASN4300003

• EXTENSIONS OF THE KARPLUS-STRONG PLUCKED-STRING ALGORITHM COMPUTER MUSIC JOURNAL Jaffe, D. A., Smith, J. O. 1983; 7 (2): 56-69

  View details for Web of Science ID A1983QT84000004

• A CONSTANT-GAIN DIGITAL RESONATOR TUNED BY A SINGLE COEFFICIENT COMPUTER MUSIC JOURNAL Smith, J. O., ANGELL, J. B. 1982; 6 (4): 36-40

  View details for Web of Science ID A1982PU40500007