The ageing of populations is increasing pressure on health and social care systems. Potentially, assistive technologies are a way to support the independence of older adults in their daily activities. Among existing assistive technologies, ambient sensing technologies have received less attention than wearable systems. Moreover, there has been little research into cheaper technologies capable of using multiple modalities. A systematic review of the acceptability of assisted living or smart homes in the United Kingdom and the simultaneous use of sounds and vibrations in remote monitoring of assisted living or smart homes will inform and encourage the use of digital monitoring technologies. The acceptability of sensing technologies depends on whether there is any social stigma about their use, for example, the extent to which they invade privacy. The United Kingdom studies reviewed suggest a lack of measurements of the perceived efficacy or effectiveness of the monitoring devices. The primary use of vibration or acoustic technologies has been for detecting falls rather than monitoring health. The review findings suggest the need for further exploration of the acceptability and applicability of remote monitoring technologies, as well as a need for more research into the simultaneous use of sounds and vibrations in health monitoring.

On a spherical/geodesic grid where the node points are mapped, the interpolation means that the radiated output from any direction could be found.This 3D data can then be used to build up a complete map of the output of the instrument, which could be coded as a set of spherical harmonic data, facilitating easy comparison of the energy content at different frequencies between any 2 directions of radiation described as points on the sphere. 7.

The Islamic lion of the Mari-Cha Collection is a medieval hollow bronze statue, most likely originating from the Mediterranean region in the early part of the last millennium. The lower sections of its legs are missing and the statue now stands at 73cm in height. There is a large rectangular opening in the belly of the lion and a small circular opening at the mouth. Inside the lion, attached to the rear of the body, is a vase-like vessel which is orientated at a slightly downward angle. Descriptions in the literature suggest that the lion may have once roared. The ancient Ghumdan palace in Sana’a, Yemen is reported as having a “yellow brass” lion statue on each of its corners and it is stated that the wind would pass through these statues and make the sound of a wild beast roaring. Also, the Byzantine emperor’s throne is described as having lions positioned around it (made either of bronze or gold-covered wood) which gave a “dreadful roar”. This paper speculates on the mechanisms by which the Mari-Cha lion may once have roared and presents some very basic measurements of the resonant frequencies of the surviving lion structure.

A hybrid wind instrument generates self-sustained sounds via a real-time interaction between a computed physical model of an exciter (such as human lips interacting with a mouthpiece) and a real acoustic resonator. Successful implementation of a hybrid wind instrument will not only open up new musical possibilities but will also provide a valuable research tool. However, attempts to produce a hybrid instrument have so far fallen short, in terms of both the accuracy and the variation in the sound produced. The principal reason for the failings of previous hybrid instruments is the actuator which, controlled by the physical model of the exciter, introduces a fluctuating component into the air flow injected into the resonator. In the present paper, the possibility of using a loudspeaker to supply the calculated excitation signal is explored. A theoretical study using established physical models is carried out, yielding useful rules for choosing the best loudspeaker for a given resonator. Acoustical coupling and feedback stability are considered. Experimental studies are reported which provide the loudspeaker's electrical input to dynamic volume flow rate transfer function. Simulations of the entire system, along with initial experimental investigations, confirm a coherent self-sustained operation.

Physical differences between musical wind instruments lead to differences in their resonance properties and, consequently, in their playing characteristics. In this paper, input impedance measurements of notes from E3 to G6 in chromatic order are made on five clarinets of different makes; altogether a total of 200 measurements. A new approach to analysing differences between the magnitudes and frequencies of the peaks across a large number of impedance curves is presented. Three variations of the analysis approach are described as it is refined to give more useful results. Observed differences in the impedance curves are used to make predictions about some of the playing characteristics for particular notes on the five clarinets, for example their relative intonations and playabilities. Finally, initial results comparing differences in the impedance curves with the results of playing perception tests are discussed.

In order to investigate whether a lip-reed instrument's material of manufacture plays a significant role in determining the timbre of the notes it produces, tests have been conducted on five post horns. These post horns have identical geometry but are manufactured from different copper alloys. Using a laser Doppler vibrometer, the structural resonances of each instrument have been established and the wall vibrations induced in each instrument when artificially blown have been measured. In this paper, these measurements are compared with findings from a series of blindfold playing tests carried out using professional musicians and with listening tests comprising notes produced by the different instruments.

Historical woodwind instruments in museums or private collections often cannot be played, by virtue of their poor condition or the risk of damage. Acoustic impedance measurements may usually be performed on instruments in good condition without risk of damage, but only if they are in playable condition: complete, with functioning mechanism, well-sealing pads and no open cracks. Many museum specimens are not in this condition. However, their geometry may almost always be accurately measured, and the measurements used to calculate the acoustic impedance as a function of frequency via a computer model of the body of the instrument. Conclusions may then be drawn about the instrument’s pitch, intonation, temperament, fingerings, effects of bore shrinkage and even the timbre of the notes. A simple linear, plane- and spherical-wave computational model, originally developed for calculating the acoustic impedance of conical-bore woodwinds, is here applied to bass clarinets for the first time. The results are assessed by experimental impedance measurements and by playing tests on an historical Heckel bass clarinet in A of 1910 that has been continuously maintained in playing condition but has been relatively lightly used. The degree of agreement between the acoustic measurements and the calculations, the required measurement accuracy and the potential and limitations of the method are discussed, and specific conclusions for this instrument are drawn. Measurement of the frequencies produced in playing tests allowed us quantitatively to estimate the effects of mouthpiece and reed on the pitch of the produced notes. The method is shown to be a viable method for the examination of historical woodwind instruments.

La sourdine est un accessoire utilise par les musiciens de cuivres pour modifier le timbre ou le niveau sonore des instruments. Il arrive cependant que les sourdines aient egalement des effets nefastes sur la jouabilite des instruments. En particulier, la sourdine seche de trombone, assimilable a un resonateur a un degre de liberte, permet d’attenuer le son tout en le rendant plus nasillard, mais rend difficile la jouabilite de certaines notes parmi les plus basses. Lorsque la sourdine est inseree dans le pavillon de l’instrument, leur couplage genere un ”pic parasite” entre les deux premieres resonances de l’impedance d’entree de l’instrument. Pour etudier le role de ce pic dans la perte de jouabilite, sa frequence et son amplitude sont modifiees via controle actif. Pour se faire, la sourdine est equipee d’un microphone et d’un haut-parleur, relies par un systeme de controle par gain et dephasage. L’effet de ce controle sur la fonction de transfert de la sourdine, l’impedance d’entree du trombone et en situation de jeu est etudie. L’effet nefaste est du a une diminution de l’amplitude de l’impedance en amont du pic parasite. Le controle permet de supprimer cet effet, ou de le deplacer sur d’autres notes.

These sounds are produced by the hybrid wind instrument with a single-reed excitation and by an entirely simulated wind instrument. The mouthpiece parameters are varied so as to evaluate both attack and sustained sounds over the stable operation range of the hybrid instrument. These results are discussed in depth in a paper on the development and evaluation of the hybrid wind instrument (to appear).

It is well established that musical sounds comprising multiple partials with frequencies approximately in the ratio of small integers give rise to a strong sensation of pitch even if the lowest or fundamental partial is missing-the so-called virtual pitch effect.Experiments on thirty test subjects demonstrate that this virtual pitch is shifted significantly by changes in the spacing of the constituent partials.The experiments measured pitch by comparison of sounds of similar timbre and were automated so that they could be performed remotely across the Internet.Analysis of the test sounds used shows that the pitch shifts are not predicted by Terhardt's classic model of virtual pitch.The test sounds used were modelled on the sounds of church bells, but a further experiment on seventeen test subjects showed that changes in partial amplitude only had a minor effect on the pitch shifts observed, and that a pitch shift was still observed when two of the lowest frequency partials were removed, so that the effects reported are of general interest.

A hybrid wind instrument generates self-sustained sounds via a real-time interaction between a computed excitation model (such as the physical model of human lips interacting with a mouthpiece) and a real acoustic resonator. Attempts to produce a hybrid instrument have so far fallen short, in terms of both the accuracy and the variation in the sound produced. The principal reason for the failings of previous hybrid instruments is the actuator which, controlled by the excitation model, introduces a fluctuating component into the air flow injected into the resonator. In the present paper, the possibility of using a loudspeaker to supply the calculated excitation signal is evaluated. A theoretical study has facilitated the modeling of the loudspeaker-resonator system and the design of a feedback and feedforward filter to successfully compensate for the presence of the loudspeaker. The resulting self-sustained sounds are evaluated by a mapping of their sound descriptors to the input parameters of the physical model of the embouchure, both for sustained and attack sounds. Results are compared with simulations. The largely coherent functioning confirms the usefulness of the device in both musical and research contexts.

A hybrid wind instrument is constructed by putting a theoretical excitation model (such as a real-time computed physical model of a clarinet embouchure) in interaction with a real wind instrument resonator. In previous work, the successful construction of a hybrid wind instrument has been demonstrated, with the interaction facilitated by a loudspeaker and a microphone placed at the entrance of a clarinet-like tube. The present paper focuses on some key findings, concentrating particularly on the “musical instrument” and “research tool” perspectives. The limitations of the hybrid set-up are considered. In particular, the choice of the loudspeaker used in the set-up is explained and the occurrence (and prevention) of instabilities during the operation of the hybrid instrument are discussed. For the design of excitation models used to drive the hybrid instrument, the usefulness of dimensionless and reduced parameter forms is outlined. In contrast to previously reported physically based excitation models, it is demonstrated that a purely mathematical “polynomial model” enables an independent control of separate sound features. For all excitation models, the sounds produced with the hybrid instrument are shown to match to those predicted by simulation. However, the hybrid instrument is more easily destabilized for certain extreme parameter states.

Tonal affinity is the perceived goodness of fit of successive tones. It is important because a preference for certain intervals over others would likely influence preferences for, and prevalences of, “higher-order” musical structures such as scales and chord progressions. We hypothesize that two psychoacoustic (spectral) factors—harmonicity and spectral pitch similarity—have an impact on affinity. The harmonicity of a single tone is the extent to which its partials (frequency components) correspond to those of a harmonic complex tone (whose partials are a multiple of a single fundamental frequency). The spectral pitch similarity of two tones is the extent to which they have partials with corresponding, or close, frequencies. To ascertain the unique effect sizes of harmonicity and spectral pitch similarity, we constructed a computational model to numerically quantify them. The model was tested against data obtained from 44 participants who ranked the overall affinity of tones in melodies played in a variety of tunings (some microtonal) with a variety of spectra (some inharmonic). The data indicate the two factors have similar, but independent, effect sizes: in combination, they explain a sizeable portion of the variance in the data (the model-data squared correlation is r 2 = .64). Neither harmonicity nor spectral pitch similarity require prior knowledge of musical structure, so they provide a potentially universal bottom-up explanation for tonal affinity. We show how the model—as optimized to these data—can explain scale structures commonly found in music, both historical and contemporary, and we discuss its implications for experimental microtonal and spectral music.

This paper reports the experimental results of modifying the resonances of wind instruments using modal active control. Resonances of a simplified bass clarinet without holes (a cylindrical tube coupled to a bass clarinet mouthpiece including a reed) are adjusted either in frequency or in damping in order to modify its playing properties (pitch, strength of the harmonics of the sound, transient behaviour). This is achieved using a control setup consisting of a co-located loudspeaker and microphone linked to a computer with data acquisition capabilities. Software on the computer implements an observer (which contains a model of the system) and a controller. Measuring and adjusting the transfer function between the speaker and microphone of the control setup enables modifications of the input impedance and the radiated sound of the instrument.

A mute is a device that is placed in the bell of a brass instrument to alter its sound. However, when a straight mute is used with a brass instrument, the frequencies of its first impedance peaks are slightly modified, and a mistuned, extra impedance peak appears. This peak affects the instrument's playability, making some lower notes difficult or impossible to produce when playing at low dynamic levels. To understand and suppress this effect, an active mute with embedded microphone and speaker has been developed. A control loop with gain and phase shifting is used to control the damping and frequency of the extra impedance peak. The stability of the controlled system is studied and then the effect of the control on the input impedance and radiated sound of the trombone is investigated. It is shown that the playability problem results from a decrease in the input impedance magnitude at the playing frequency, caused by a trough located on the low frequency side of the extra impedance peak. When the extra impedance peak is suppressed, the playability of the note is restored. Meanwhile, when the extra impedance peak is moved in frequency, the playability problem position is shifted as well.