Joe Wolfe

UNSW Sydney | UNSW · School of Physics

Measuring fine-grained physical interaction between the human player and the musical instrument can significantly improve our understanding of music performance. This article presents a Musical Instrument Performance Capture and Analysis Toolbox (MIPCAT) that can be used to capture and to process the physical control variables used by a musician wh...

Men and women speakers were recorded while producing sustained vowels at comfortable and loud levels. Following comfortable speech, loud levels were produced in three different conditions: first without specific instruction (UL); then maintaining the same pitch as the comfortable level (PL); and finally, keeping both pitch and lip articulation cons...

Music can convey emotions. Even in the performance of written rather than improvised music, the performer can modify the way they play particular elements of the music to convey specific emotions. Considerable research attention has been paid to the ways in which performers convey a small set of so-called basic emotions. In the current work, we inv...

Volume 2 of the Oxford Handbook of Music Performance is designed around four distinct parts: Enhancements, Health and Wellbeing, Science, and Innovations. Chapters on the popular Feldenkrais method and Alexander technique open the volume, and these lead to chapters on peak performance and mindfulness, stage behavior, impression management and chari...

In music, vibrato consists of cyclic variations in pitch, loudness, or spectral envelope (hereafter, “timbre vibrato”—TV) or combinations of these. Here, stimuli with TV were compared with those having loudness vibrato (LV). In Experiment 1, participants chose from tones with different vibrato depth to match a reference vibrato tone. When matching...

Purpose Over a range roughly C5–C6, sopranos usually tune their first vocal tract resonance (R1) to the fundamental frequency (f o) of the note sung: R1:f o tuning. Those who sing well above C6 usually adjust their second vocal tract resonance (R2) and use R2:f o tuning. This study investigated these questions: Can singers quickly learn R2:f o tun...

To study the effect of ‘warming up’ a wind instrument, the acoustic impedance spectrum at the mouthpiece of a trombone was measured after different durations of playing. When an instrument filled with ambient air is played in a room at 26–27 °C, the resonance frequencies initially fall. This is attributed to CO 2 in the breath initially increasing...

Trombonists normally play at a frequency slightly above a bore resonance. However, they can “lip up and down” to frequencies further above the resonance (more compliant load) and below (inertive load). This was studied by determining the pressures, flows, and acoustic impedance upstream and downstream and by analyzing high-speed video of the lips....

Reflections on the decibel lead Joe Wolfe and Oleg Sushkov to considerations of infinite waveguides and to why we didn’t hear the LIGO black-hole merger.

No PDF available ABSTRACT The acoustic impedance spectrum of the vocal tract and trachea is important in speech and singing. The operation of musical wind instruments depends on the impedance spectra of their bores, and sometimes also on the impedance spectra of the player’s vocal tract. Here, we describe two measurement techniques. The three micro...

Players coordinate tongue release and variation in blowing pressure to produce a range of desired initial transients, e.g. for accents and sforzando, players use higher pressures at release to give higher rise rates in the exponential stage. The mechanisms were studied with high-speed video and acoustic measurements on human and artificial players...

The first resonance of the vocal tract (R1, an impedance minimum when measured at the lips) is tuned by some singers: all of the sopranos we have studied, whether trained or not, tune R1 to fo over the range roughly C5 to C6; altos and tenors sometimes tune it to one of the lower harmonics in their upper range. Sopranos who sing in the range substa...

Broadband excitation of the vocal tract at the lips (Epps, Smith & Wolfe, 1997. Meas. Sci. Technol. 8, 1112–1121 [1]) has been used by the present authors and in other laboratories to estimate the resonances of the vocal tract in ‘ecological’ conditions of speaking and singing. A sound source and microphone are both held at the lower lip of the sub...

Notes produced by self-sustained musical wind instruments are characterised by relatively long stretches of sound where the waveform has limited variation. However, for notes begun by tonguing, the initial transient or attack is characterised by a rapid, nearly exponential rise in the amplitude of the pressure oscillations. In recent articles, we h...

Determining the area function A(x) of the airway between the lips and vocal folds from external measurements is a classic inverse problem. A(x) is estimated by fitting the acoustic impedance measured through the lips. Excellent fits are possible with about eight cylindrical segments representing the tract. In examples where A(x) has only small slop...

We describe a method to deduce pressure and flow at the glottis from acoustic measurements near or downstream from the lips, using phonation into a cylindrical duct with three microphones. In this paper this method is tested on hard one-dimensional ducts, also reporting the precision of using 3D printed models of vocal tract area functions. Combini...

Experimental determinations of the acoustic properties of the subglottal airway, from the trachea below the larynx to the lungs, may provide useful information for detecting airway pathologies and aid in the understanding of vocal fold auto-oscillation. Here, minimally invasive, high precision impedance measurements are made through the lips (7 men...

In self-sustained instruments, starting transients are important timbral characteristics that help identify the instrument and the playing style. Often, the oscillation starts as a growing exponential. This study investigates the starting amplitude of this exponential for the clarinet. After a rapid tongue release, the reed quickly returns to its e...

Brightness is an attribute often used by musicians when describing timbral characteristics. It is related to the spectral distribution of energy, as is sharpness, studied by Zwicker (Psychoacoustics: Facts and Models,1990). In the current work, subjects adjusted the spectral slope and thus the spectral centroid (SC) of one of a pair of sounds to ma...

During speech and singing, the vibrating vocal folds are acoustically loaded by resonant ducts upstream (the trachea) and downstream (the vocal tract). Some models suggest that the vocal fold vibration (at frequency fo) is more stable at frequencies below that of a vocal tract resonance, so that the downstream load is inertive (mass-like). If so, v...

Sometimes, the beauty of a single note identifies a good musician: The initial and final transients are controlled appropriately, as is the harmonic content of the sustained part. This study reports first how several control parameters are varied by accomplished players of clarinet and saxophone. It then uses measurements on a clarinet-playing mach...

A beautiful note should have appropriate pitch, loudness and timbre, and be elegantly articulated. On the clarinet and saxophone, the frequency, sound level, spectral envelope and articulation can be controlled using a learned coordination of breath pressure, lip force, tongue motion and vocal tract shape. But how do players achieve this and how do...

Acoustic impedance spectrometry using the three-microphone, three-calibration technique has recently been applied to the vocal tract during phonation (Hanna et al., 2016. JASA, 139, 2924–2936). The qualitative and quantitative similarity of the impedance spectrum of the vocal tract with a simple cylindrical duct prompts the question: How well do ge...

Oscillating vocal folds are acoustically loaded by resonant ducts upstream (trachea) and downstream (vocal tract). The soprano frequency range covers the first resonance in each duct; indeed, sopranos often tune their vocal tract resonance (R1) near the singing frequency. What happens when R1 is removed? In this study, sopranos sang into an acousti...

Wind instrument players control the initial and final transients of notes using breath, lips, and tonguing. This paper uses a clarinet-playing machine and high-speed camera to investigate how blowing pressure, lip force, and tonguing parameters affect transients. After tongue release, the reed quickly comes to rest, losing its mechanical energy. Ho...

A three-domain pressure–volume relationship (PV curve) was studied in relation to leaf anatomical structure during dehydration in the grey mangrove, Avicennia marina. In domain 1, relative water content (RWC) declined 13% with 0.85 MPa decrease in leaf water potential, reflecting a decrease in extracellular water stored primarily in trichomes and p...

The frequencies, magnitudes, and bandwidths of vocal tract resonances are all important in understanding and synthesizing speech. High precision acoustic impedance spectra of the vocal tracts of 10 subjects were measured from 10 Hz to 4.2 kHz by injecting a broadband acoustic signal through the lips. Between 300 Hz and 4 kHz the acoustic resonance...

A known acoustic flow is generated and input to a physical (hardware) model of a vocal tract at its ’glottis’. The output sound is measured, along with the gain of the tract (the transpedance or transimpedance: the ratio of output pressure to input flow). These allow all stages of the Source–Filter model to be illustrated by actual experimental mea...

What makes an artificial musical instrument such as the flute, trombone or cello sound like the human voice, and which of all instruments is the most voicelike? This article reviews acoustical and psychological arguments that might explain why a musical instrument would be likened to the singing human voice. The authors could find no evidence to su...

Articulation, including initial and final note transients, is important to tasteful music performance. Clarinettists' tongue-reed contact, the time variation of the blowing pressureP¯mouth, the mouthpiece pressure, the pressure in the instrument bore, and the radiated sound were measured for normal articulation, accents, sforzando, staccato, a...

To play a reed instrument well, players control pitch, loudness, timbre and articulation (transient behaviour). But which control parameters do they use to achieve this, and how do they coordinate their actions? In the 'ecological' phase of this project, we measured the acoustical impedance of the vocal tract, the blowing pressure and its time vari...

Analysis of published depth-kymography data (George et al. 2008, Phys. Med. Biol. 53, 2667) shows that, for the subject studied, the flow due to the longitudinal sweeping motion of the vocal folds contributes several percent of a typical acoustic flow at the larynx. This sweeping flow is a maximum when the glottis is closed. This observation sugges...

Protoxylem plays an important role in the hydraulic function of vascular systems of both herbaceous and woody plants, but relatively little is known about the processes underlying maintenance of protoxylem function in long-lived tissues. In the present study, embolism repair was investigated in relation to xylem structure in two cushion plant speci...

Scitation is the online home of leading journals and conference proceedings from AIP Publishing and AIP Member Societies

This article reports three studies about performance of lieder, and in particular in comparison with opera performance. In study 1, 21 participants with experience in music performance and teaching completed a survey concerning various characteristics of lieder performance. The results showed that there was consensus between the literature and the...

To play a wind instrument well, the player controls several elements in the player-instrument system, beginning with the source of pressurised air in the lungs. The bore of the instrument is a resonant duct whose geometry is controlled by the player's fingers via keys, valves or a slide. At the mouthpiece the player controls several parameters of a...

Variation in the radiated sound spectrum, p rad, is an expressive technique that can be achieved on the saxophone by employing diff erent vocal tract configurations that change the vocal tract impedance spectrum Z mouth. However, the relation between p rad and the vocal tract impedance spectrum Z mouth has not previously been measured for orchestra...

This experimental study investigates ten subjects playing the trombone in the lower and mid-high range of the instrument, B♭2 to F4. Several techniques are combined to show the pressures and the impedance spectra upstream and downstream of the lips, the acoustic and total flows into the instrument, the component of the acoustic flow due to the swee...

On the macroscopic scale, biology obeys thermodynamics, and this article introduces the laws of thermodynamics and its macroscopic variables, including entropy. The molecular description is often more directly useful to biologists. So this article explains Boltzmann's distribution, which describes how the proportion of molecules having a particular...

Good clarinet playing requires careful articulation and independent control of pitch, loudness and timbre. For articulation, the tongue produces rapid pressure changes and damps or displaces the reed to obtain initial transients. In sustained playing, frequency, sound level and sound spectrum depend on the pressure P in the mouth, the lip force F a...

A simple digital method is described that can produce an undistorted acoustic sine wave using an amplifier and loudspeaker having considerable intrinsic distortion, a common situation at low frequencies and high power. The method involves, first, using a pure sine wave as the input and measuring the distortion products. An iterative procedure then...

Simple physical models describe the motion of brass player's lips as a superposition of two modes: in one, the upper lip bends like a cantilever into the mouthpiece; in the other, one or both lips undergo vertical strain to vary the aperture. These motions are investigated here on a trombone using high speed video and microphones to record mouth an...

Articulation – the skilful control of transients – is one vital part of good playing of wind instruments. Another is the ability to control pitch, loudness and timbre independently. In the steady state, the frequency, sound level and sound spectrum depend on the steady pressure P in the mouth, the force F and its point of application to the reed by...

Articulation is one of the most important techniques of playing wind instruments, and it requires skilful control of the tongue. Clarinettists use their tongues in coordination with rapid mouth pressure changes to initiate transients. An expert player studied here produces accented and sforzando notes with the fastest increases in pressure, startin...

A simple digital method is described that can produce an undistorted acoustic sine wave using an amplifier and loudspeaker having considerable intrinsic distortion, a common situation at low frequencies and high power. The method involves, first, using a pure sine wave as the input and measuring the distortion products. An iterative procedure then...

Horn players have observed that timpani strokes can interfere disruptively with their playing, especially when they are seated close to the timpani. Measuring the horn's transfer function in the bell-to-mouthpiece direction reveals that the horn behaves as an acoustic impedance matching device, capable of transmitting waves with pressure gains of a...

Seven male operatic singers sang the same notes and vowels in their chest and their falsetto registers, covering the overlap frequency range where two main laryngeal mechanisms can be identified by means of electroglottography: M1 in chest register and M2 in falsetto register. Glottal contact quotients determined using electroglottography were typi...

Articulation - the skilful control of transients - is one vital part of good playing of wind instruments. Another is the ability to control pitch, loudness and timbre independently. In the steady state, the frequency, sound level and sound spectrum depend on the steady pressure P in the mouth, the force F and its point of application to the reed by...

Using an automated clarinet playing system, the frequency f, sound level L, and spectral characteristics are measured as functions of blowing pressure P and the force F applied by the mechanical lip at different places on the reed. The playing regime on the (P,F) plane lies below an extinction line F(P) with a negative slope of a few square centime...

We report the motion of trombone players' lips, its phase with respect to the mouthpiece pressure, the impedances of the bore and the player's vocal tract, and the frequency difference between the bore resonance and played note. The bore resonance frequency shifts very little with playing and often decreases somewhat: the effect of CO 2 can exceed...

The results of an on-line study of vowel recognition by English speakers are analysed. A relatively unused region of the perceptual vowel plane is identified at about (F2, F1) = (1800 Hz, 350 Hz). The rest of the plane is divided among vowels in ways that differ somewhat for different countries and regions thereof. Vowel length is used in several c...

Players control a range of parameters in the player-instrument system. First we show how loudness and pitch vary over the plane of mouth pressure and force on the reed of a clarinet, and thus how these parameters can be used in compensation to produce trajectories in this plane that have varying loudness and timbre but constant pitch. Next we prese...

The UNSW Music Acoustics site provides a learning experience for its users, but it has also provided one for its makers. This paper describes how it was made and some of what we learned in making it. It also describes a new, larger project, called Physclips, which is being made with a consistent philosophy, in the light of our experience. We descri...

For notes sounded over the normal and altissimo playing range, experienced saxophonists can produce changes in the spectral envelope of the radiated sound by adjusting their vocal tract configuration. Measurements of the vocal tract acoustic impedance, Zmouth, during performance showed that, when Zmouth was comparable with the input impedance of th...

The aeroacoustic properties of the vocal folds and tract are difficult to measure directly. Here, they were measured using broad- and narrow-band excitation at the mouth during phonation into various acoustic loads, including a non-resonant load provided by an acoustically infinite waveguide with cross section comparable with that of the tract. The...

In most wind instruments, the acoustic output is generated by airflow through a non-linear valve, whose sounding frequency is largely determined by resonances in the bore of the instrument (an acoustic duct downstream of the valve) and mechanical properties of the non-linear valve that converts DC to AC power. The player's vocal tract (a second duc...

The technique presented here uses an impedance head to measure the input impedance spectrum of a physical model of a vocal tract, and then to inject a known glottal flow waveform into the tract. The sound measured outside the mouth is used to evaluate inverse filtering techniques by comparison with the known glottal flow and measured acoustical pro...

The bandwidths of vocal tract resonances are critical: too narrow allows speech harmonics to miss resonances, too broad gives insufficient boost to identify phonemes.

The impedance spectrum of the vocal tract was measured at the lips from 10 Hz to 4.2 kHz using the three-microphone, three-calibration technique. A broadband signal synthesised from sine waves allows high precision measurements irrespective of the fundamental frequency of phonation. From these measurements, the frequencies, magnitudes and bandwidth...

Physclips provides multimedia resources to physics students and teachers at the levels of senior high school to introductory university. Completed volumes cover mechanics, waves and sound. Each chapter includes a rich multimedia lesson of about 10 minutes, including film clips, animations, sound files and images of key experiments and demonstration...

Relating objective acoustical measurements of an instrument, without a player, to the qualities reported by players is often a difficult goal in music acoustics. The didjeridu offers advantages in such a study because it is inherently 'blind'-neither player nor researcher knows what is inside-and because there are wide variations in objective param...

Conference presentation at ICVPB

The wide range of the singing voice, from below C2 (65 Hz) to above F6 (1397 Hz), requires a number of strategies that can involve different mechanisms of laryngeal vibration and various adjustments of the vocal tract resonances. The adjustments are made because a vocal tract resonance can boost the radiation of a voice harmonic when it falls close...

The acoustic impedance spectrum was measured in the mouths of seven trumpeters while they played normal notes and while they practiced "bending" the pitch below or above the normal value. The peaks in vocal tract impedance usually had magnitudes rather smaller than those of the bore of the trumpet. Over the range measured, none of the trumpeters sh...

The high soprano range was investigated by acoustic and electroglottographic measurements of 12 sopranos and high-speed endoscopy of one of these. A single laryngeal transition was observed on glissandi above the primo passaggio. It supports the existence of two distinct laryngeal mechanisms in the high soprano range: M2 and M3, underlying head and...

The assimilation of complex transient information is limited by the learners cognitive processing ability and their level of prior knowledge. As such it is incumbent on educators and instructional designers to be familiar with evidence based guidelines in the field of multimedia learning and also to be cognizant of the pivotal role undertaken by th...