Musical Tones Research Articles

Auditory effect of perturbing musical tones by interpolation with other musical tones.

The effect of blending variable amounts of a secondary tone with a primary tone by means of interpolating between their corresponding harmonic amplitudes was investigated. Original tones (bassoon, clarinet, flute, horn, oboe, alto saxophone, trumpet, and violin) were normalized with respect to fundamental frequency, duration, attack and decay times, and loudness; also, harmonic frequencies were flattened. However, the basic time variations of the tones' harmonic amplitudes were preserved. Interpolation was accomplished in the frequency domain using interpolation levels between 5 and 50%. While the effect of perturbation is highly dependent on the primary/secondary instrument pair, results show that the effect of a secondary instrument is heard most easily for primary instruments horn and bassoon and least easily for primary instruments trumpet and saxophone. On the other hand, clarinet and trumpet are heard most easily as secondary instruments, whereas bassoon and violin are slow to be heard. Discrimination scores were correlated with different spectrotemporal measures of the tone spectra: spectral incoherence, normalized spectral centroid deviation, and spectral irregularity. The only significant effect found was that primary instruments with high spectral incoherence tend to mitigate against perturbation by secondary instruments. [Work supported by Research Grants Council Grants 613806 and 613508.]

Multidimensional perceptual scaling of musical timbre by hearing‐impaired listeners.

We examine the impact of hearing loss and hearing aid processing on the perception of musical timbre. Our objective is to identify significant timbre cues for hearing‐impaired listeners, and to assess the impact of hearing aid signal processing on timbre perception. Hearing aids perform dynamic, level‐dependent spectrum shaping that may influence listeners’ perception of musical instrument timbres and their ability to discriminate among them. Grey [“Multidimensional perceptual scaling of musical timbres,” J. Acoust. Soc. Am. 61, 1270 (1977)] showed that sustaining instrument tones equalized for level, loudness, and duration are distinguished primarily along three perceptual dimensions that are strongly correlated with the acoustical dimensions of: (1) spectral energy distribution, (2) spectral fluctuation, and (3) precedent high‐frequency, low‐amplitude energy. Following the work of Grey, we ask listeners having mild to moderately severe sensorineural hearing loss to rate pairs of synthetic musical instrument tones according to dissimilarity in aided and unaided conditions. We analyze the dissimilarity judgments to identify acoustical correlates for the significant dimensions of timbre discrimination. This analysis helps us to objectively estimate the impact of hearing aid signal processing on the ability of hearing‐impaired listeners to discriminate among musical instruments, an important component of musical listening.

From domain-generality to domain-sensitivity: 4-Month-olds learn an abstract repetition rule in music that 7-month-olds do not

Learning must be constrained for it to lead to productive generalizations. Although biology is undoubtedly an important source of constraints, prior experience may be another, leading learners to represent input in ways that are more conducive to some generalizations than others, and/or to up- and down-weight features when entertaining generalizations. In two experiments, 4-month-old and 7-month-old infants were familiarized with sequences of musical chords or tones adhering either to an AAB pattern or an ABA pattern. In both cases, the 4-month-olds learned the generalization, but the 7-month-olds did not. The success of the 4-month-olds appears to contradict an account that this type of pattern learning is the provenance of a language-specific rule-learning module. It is not yet clear what drives the age-related change, but plausible candidates include differential experience with language and music, as well as interactions between general cognitive development and stimulus complexity.

Detection of time-varying harmonic amplitude alterations due to spectral interpolations between musical instrument tones

Gradated spectral interpolations between musical instrument tone pairs were used to investigate discrimination as a function of time-averaged spectral difference. All possible nonidentical pairs taken from a collection of eight musical instrument sounds consisting of bassoon, clarinet, flute, horn, oboe, saxophone, trumpet, and violin were tested. For each pair, several tones were generated with different balances between the primary and secondary instruments, where the balance was fixed across the duration of each tone. Among primary instruments it was found that changes to horn and bassoon [corrected] were most easily discriminable, while changes to saxophone and trumpet timbres were least discriminable. Among secondary instruments, the clarinet had the strongest effect on discrimination, whereas the bassoon had the least effect. For primary instruments, strong negative correlations were found between discrimination and their spectral incoherences, suggesting that the presence of dynamic spectral variations tends to increase the difficulty of detecting time-varying alterations such as spectral interpolation.

Electronic musical instrument

There is provided an electronic musical instrument which is capable of muting by a simple operation. A plurality of fret operating elements are provided on a fingerboard, for determining the pitch. Six stringed operating elements for determining sounding timing are provided on a string input section of the body of the electronic musical instrument. A tone generator and a sound system generate musical tones according to operations of the fret operating elements and the stringed operating elements. A mute fingerboard larger in transverse size than the transverse region over which the six stringed operating elements are arranged is disposed on an operating element holder protecting section engaged with latches of the operating elements. The mute fingerboard is located in the vicinity of operated ends of the stringed operating elements within the range where the stringed operating elements can be operated, and is exposed on a surface of the body.

Stereo sounding method, stereo sounding system, and musical tone generation control system

A stereo sounding method which can provide realistic sounds such as stereo sounds for a large number of listeners while reducing the number of speakers. A stereo sounding system is comprised of a plurality of stereo sound sources, and a plurality of speakers. A smaller number of speakers than twice the number of the plurality of stereo sound sources are arranged, and an R-channel output from at least one stereo sound source among the plurality of stereo sound sources and an L-channel output from a stereo sound source other than the at least one stereo sound source are mixed, and the mixing result is output to at least one of the arranged speakers.

Effects of musical training on brain development.

The auditory cortex builds representations of the auditory environment based on the characteristics of its input. I will present EEG and MEG data showing that, compared to non‐musicians, adult musicians have enhanced responses to isolated musical tones, melodic sequences, and simultaneous melodies. Whether these differences are the result of musical experience is explored through training studies in adults and longitudinal studies comparing children engaged in musical lessons with children engaged in other activities. It will be shown that auditory sensory representations undergo a protracted developmental trajectory, not reaching adult states until well into the teenage years. Furthermore, the effects of musical experience can be seen in children as young as 4–5 years of age for both sensory and attentional components of the event‐related potential. High‐frequency oscillatory EEG activity (induced gamma band), which is associated with executive control, attention, and memory, emerges after 1 year of music lessons in children of this age, but is not seen in children who are not taking music lessons. Thus any benefits of musical training for other cognitive domains is likely mediated by the development of superior executive functioning.

A New Way of Relieving Stress by Using Fractal Music Tones in Digital Hearing Aids

A New Way of Relieving Stress by Using Fractal Music Tones in Digital Hearing Aids

Treating hypertension in type II diabetic patients with device-guided breathing: a randomized controlled trial

The objective of the study was to evaluate the efficacy of device-guided breathing to lower blood pressure (BP) in hypertensive type II diabetic patients. A randomized controlled trial was carried out in four urban family practice clinics in Israel. Non-insulin-dependent diabetic, hypertensive patients with uncontrolled BP, receiving antihypertensive therapy or those non-medicated were enrolled. Baseline characteristics of the 66 patients who completed the study (33 intervention and 33 control) were: 62% men, age 62+/-8 years (mean+/-s.d.); body mass index 29+/-5 kg/m2; systolic BP 148+/-11 mm Hg and diastolic BP 81+/-9 mm Hg. The intervention group used a device (RESPeRATE), which interactively guides the user towards slow and regular breathing by synchronizing respiration voluntarily to musical tones for 15 min daily for an 8-week period. The control group continued with their regular treatment. BP was measured in the clinic at baseline, after 4 weeks and at 8 weeks. Medication was unchanged for 4 weeks prior to and during the study period. The main outcome measure was the office BP change from baseline to the end of the 8-week period. BP was reduced in the treatment group (mean+/-s.e.) systolic -10.0+/-1.8 mm Hg and diastolic -3.6+/-1.3 mm Hg (P<0.0001 and P<0.01), but not in the controls +1.6+/-2.1 and -1.0+/-1.4 mm Hg P>0.4 and P>0.4, respectively. Test for between group difference P<0.0001 and P=0.08. The subjects were highly compliant with the treatment, performing 75% of the requested exercise sessions. Greater BP reduction was observed with increased compliance with device usage (P=0.01 and P=0.001). It is concluded that self-treatment with device-guided breathing at home for 8 weeks by non-insulin-dependent diabetic patients was associated with a substantial reduction in office systolic BP.

Fourier Analysis of Musical Intervals

Use of a microphone attached to a computer to capture musical sounds and software to display their waveforms and harmonic spectra has become somewhat commonplace.1 A recent article in The Physics Teacher aptly demonstrated the use of MacScope2 in just such a manner as a way to teach Fourier analysis.3 A logical continuation of this project is to use MacScope not just to analyze the Fourier composition of musical tones but also musical intervals.

Device-Guided Paced Breathing in the Home Setting

Background— Regular slow breathing is known to improve autonomic cardiac regulation and reduce chemoreflex sensitivity in heart failure. We explored the acceptability and usefulness of a device for paced slow breathing at the home setting. Methods and Results— In this open pilot study, 24 patients with chronic heart failure (61% males, mean age, 64�9 years; New York Heart Association class, 2.81�0.01) were randomized to a control group receiving conventional treatment (n=12) or to a group receiving conventional treatment and device-guided paced breathing (n=12). Groups were comparable for age, therapies, and clinical characteristics. They were evaluated at baseline and again after 10 weeks by Doppler echocardiography, pulmonary function, cardiopulmonary stress test, and quality of life (Minnesota Quality of Life questionnaire). The treatment group was instructed to use the equipment for 18 minutes twice daily. The device is a computerized box connected to a belt-type respiration sensor and to headphones; it generates musical tones (based on the user’s breathing rate and inspiration ratio), which guide the user to progressively and effortlessly slow his or her breathing rate &lt;10 breaths/min. The treatment group showed high compliance to the device (90% of the prescribed sessions were completed). Blinded analysis of data demonstrated increased ejection fraction and decreased estimated pulmonary pressure in the echocardiograms of the treated group versus controls and favorable changes in New York Heart Association class, V e /V co 2 , FEV 1 , and a quality of life measure, as well (all P &lt;0.05). Conclusions— This pilot investigation demonstrates that device-guided paced breathing at home is feasible and results in an improvement in clinically relevant parameters for patients with heart failure and systolic dysfunction.

Analyzing several musical instrument tones using the randomly modulated periodicity model

The waveform of a simple sustained tone emitted from musical instruments such as a flute played by even the best musician is never exactly periodic. There is always some variation over time in the waveform of a single pitch that is characteristic of the instrument itself. In this paper, we employ the signal-coherence function introduced by Hinich [A statistical theory of signal coherence, J. Oceanic Eng. 25(2) (2000) 256–261] to study the subtle variation of tones from several instruments played by accomplished musicians. This measure characterizes the amount of variation in each Fourier component as a random amplitude-modulation component added to a coherent narrowband sinusoid. The signal-coherence function is computed from several digitized acoustic signals of several musical instruments. The signal-coherence functions show that there are important differences between the same notes produced from different instruments. The signal coherence of a vibrato, a deliberate modulation of a tone, is analyzed for the first time using the signal-coherence function. We show that for most practical playing conditions it has a small effect for lower frequencies. This allows characterization of modulation variations in sustained portions of sound with and without vibrato. The signal-coherence processing method applied to musical acoustics could lead to more realistic music synthesizers.

Canceling and Selecting Partials from Musical Tones Using Fractional-Delay Filters

Using Fractional-Delay Filters Heidi-Maria Lehtonen,* Vesa Valimaki,* and Timo I. Laakso*f * Helsinki University of Technology (TKK) Department of Signal Processing and Acoustics P.O. Box 3000, FI-02015 TKK, Espoo, Finland +National Board of Patents and Registration of Finland Patents and Innovations Line P.O. Box 1140, FI-00101, Helsinki, Finland (heidi-maria.lehtonen, vesa.valimaki, timo.laakso}® tkk.fi

MO-D-342-05: Optoacoustic Tomography Is Coming of Age

In 1880 Alexander G. Bell heard “a pure musical tone” in a closed gas volume that had absorbed a modulated sunlight beam. However, it would be a century before interest in the photoacoustic effect stimulated physicists to employ this discovery in novel medical instruments. In the beginning of the 21st century, opto‐acoustic tomography (OAT) emerged as a sensitive modality for visualization and quantitative characterization of malignant tumors and blood vessels. OAT combines the most compelling features of light and sound to provide maps of absorbed optical energy in optically scattering and opaque media including biological tissues. The new hybrid modality improves spatial resolution of the optical imaging and contrast of the ultrasound imaging. The basic principles behind the optoacousticimagingsystem are that (1) laser pulses may be effectively used to produce acoustic sources in tissues with enhanced optical absorption, and (2) ultrasonic waves propagate in biological tissues as expanding spheres with minimal wavefront distortion and deliver temporarily resolved information to the surface of tissue where it may be detected. The application of transducer arrays permits reconstruction of two‐dimensional and three‐dimensional images. One of the main endogenous chromophores of tissue in the near‐infrared spectral range is the hemoglobin of blood. Therefore, blood vessels possess high optoacousticcontrast. Malignant solid tumors develop an enhanced network of microvessels to supply nutrition and oxygen to aggressively growing cancer cells. Therefore, optical contrast between normal and canceroustissues is substantially greater than the contrast utilized in ultrasound imaging and other imaging modalities. Furthermore, functional information about hemoglobin concentration and its level of oxygen saturation in tumors can serve as a basis for noninvasive diagnostic utility of OAT. The empirical rule of thumb is that optoacoustic resolution equals depth / 100, so that at the depth of 50 mm one can obtain resolution of about 0.5 mm, while typical resolution is about 50 micron at the depth of 5 mm. Experimental schemes of optoacousticimagingsystem for two‐dimensional and three‐dimensional optoacoustictomography as well as corresponding algorithms of image reconstruction will be discussed. The niche of the optoacoustictomography in biomedical imaging is to provide high‐resolution 3D maps containing (1) functional information on blood concentration and its oxygen saturation, and (2) molecular content of endogenous or exogenous chromophores. Clinical studies performed in breast cancer patients will be presented to demonstrate that the functional imaging capability of OAT provides additional medically relevant information regarding breast tumors, which results in better sensitivity and specificity of cancer detection. The molecular imaging capability of OAT is enabled by variation of the optical wavelength for selective heating of specific chromophores administered and targeted to the site of interest. A unique opportunity for further substantial enhancement of the optoacoustic detection sensitivity comes from merging OAT with plasmonic nanotechnology. An optoacousticcontrast agent based on gold nanorods selectively delivered to cancer cells in order to substantially increase brightness of canceroustumors will be described. The same contrast agent can serve potentially as a therapeutic agent for treatment of early cancer.

Development and preliminary evaluation of a prototype audiovisual biofeedback device incorporating a patient-specific guiding waveform

The aim of this research was to investigate the effectiveness of a novel audio-visual biofeedback respiratory training tool to reduce respiratory irregularity. The audiovisual biofeedback system acquires sample respiratory waveforms of a particular patient and computes a patient-specific waveform to guide the patient's subsequent breathing. Two visual feedback models with different displays and cognitive loads were investigated: a bar model and a wave model. The audio instructions were ascending/descending musical tones played at inhale and exhale respectively to assist in maintaining the breathing period. Free-breathing, bar model and wave model training was performed on ten volunteers for 5 min for three repeat sessions. A total of 90 respiratory waveforms were acquired. It was found that the bar model was superior to free breathing with overall rms displacement variations of 0.10 and 0.16 cm, respectively, and rms period variations of 0.77 and 0.33 s, respectively. The wave model was superior to the bar model and free breathing for all volunteers, with an overall rms displacement of 0.08 cm and rms periods of 0.2 s. The reduction in the displacement and period variations for the bar model compared with free breathing was statistically significant (p = 0.005 and 0.002, respectively); the wave model was significantly better than the bar model (p = 0.006 and 0.005, respectively). Audiovisual biofeedback with a patient-specific guiding waveform significantly reduces variations in breathing. The wave model approach reduces cycle-to-cycle variations in displacement by greater than 50% and variations in period by over 70% compared with free breathing. The planned application of this device is anatomic and functional imaging procedures and radiation therapy delivery.

Case study on assessing audibility by "Perspicuity" for sounds added to factory noise, using different types of speaker in directional performance

Music and other sounds have been played to provide a pleasant sound environment for workers in a factory. In terms of "Sound Perspicuity" this case study was conducted to assess audibility of spatial sounds, which were adjusted in level without increasing total sound pressure level (SPL) at the workstation. Furthermore, the added sounds were not audible at other workstations. Three speaker systems, including line-array speaker (60 cm in length), were used for the case study. The ratio of added sound (Signal) to factory noise (Noise) was analyzed at every measuring point on a grid of 50 cm by 50 cm. Audibility listening tests were performed for the added sounds, such as natural-environment sounds and musical instrument tones, with Signal to Noise ratios analyzed from three types of speaker. As a result, a sound is recognized as "Kiwadachi" by a Japanese adjective word even when the factory noise has higher levels than the added sounds. Audibility test results for each added sound are discussed with different Signal to Noise ratios.

Overtone Spectra of Gongs used in Music Therapy

Fast Fourier Transform (FFT) study of gong sound spectrograms was carried out on four gongs manufactured by Paiste Company, Switzerland. The results show complex spectra, presented in detail in the present work, that explain the extraordinary sound of the gongs. Each gong has its unique spectrum and its unique time-decay characteristics. The overtone series of the gongs include consonant and dissonant intervals, and have no relation to the harmonic overtone series of musical tones. The theory of an ideal circular membrane was applied in computation of the overtone spectrum of one gong (“World” gong), leading to very good agreement between computed and measured data. Comparison of gongs to other percussions is discussed, and, in particular, a comparison is made with spectra of church bells, vibraphone, and Tibetan singing bowl. The overtone series of the various gongs were found to provide satisfactory explanation to the effect of the gongs on patients subjected to music therapy with gongs. In addition, a special case history of an effect of certain percussion sounds, of interest to music therapy, is described and interpreted with the help of results of FFT analysis.

Vibration source driving device

A vibration source driving device that realizes various vibration functions on portable telephones. The vibration source driving device includes a sound source for generating musical tone signals in response to music data. A vibration source to generate vibration, a driver to drive the vibration and a control circuit are further included such that the vibration source may be driven in synchronization with the rhythm signal within the music data.

Neural specializations for speech and pitch: moving beyond the dichotomies

The idea that speech processing relies on unique, encapsulated, domain-specific mechanisms has been around for some time. Another well-known idea, often espoused as being in opposition to the first proposal, is that processing of speech sounds entails general-purpose neural mechanisms sensitive to the acoustic features that are present in speech. Here, we suggest that these dichotomous views need not be mutually exclusive. Specifically, there is now extensive evidence that spectral and temporal acoustical properties predict the relative specialization of right and left auditory cortices, and that this is a parsimonious way to account not only for the processing of speech sounds, but also for non-speech sounds such as musical tones. We also point out that there is equally compelling evidence that neural responses elicited by speech sounds can differ depending on more abstract, linguistically relevant properties of a stimulus (such as whether it forms part of one's language or not). Tonal languages provide a particularly valuable window to understand the interplay between these processes. The key to reconciling these phenomena probably lies in understanding the interactions between afferent pathways that carry stimulus information, with top-down processing mechanisms that modulate these processes. Although we are still far from the point of having a complete picture, we argue that moving forward will require us to abandon the dichotomy argument in favour of a more integrated approach.

Kalman tracking of linear predictor and harmonic noise models for noisy speech enhancement

This paper presents a speech enhancement method based on the tracking and denoising of the formants of a linear prediction (LP) model of the spectral envelope of speech and the parameters of a harmonic noise model (HNM) of its excitation. The main advantages of tracking and denoising the prominent energy contours of speech are the efficient use of the spectral and temporal structures of successive speech frames and a mitigation of processing artefact known as the ‘musical noise’ or ‘musical tones’. The formant-tracking linear prediction (FTLP) model estimation consists of three stages: (a) speech pre-cleaning based on a spectral amplitude estimation, (b) formant-tracking across successive speech frames using the Viterbi method, and (c) Kalman filtering of the formant trajectories across successive speech frames. The HNM parameters for the excitation signal comprise; voiced/unvoiced decision, the fundamental frequency, the harmonics’ amplitudes and the variance of the noise component of excitation. A frequency-domain pitch extraction method is proposed that searches for the peak signal to noise ratios (SNRs) at the harmonics. For each speech frame several pitch candidates are calculated. An estimate of the pitch trajectory across successive frames is obtained using a Viterbi decoder. The trajectories of the noisy excitation harmonics across successive speech frames are modeled and denoised using Kalman filters. The proposed method is used to deconstruct noisy speech, de-noise its model parameters and then reconstitute speech from its cleaned parts. Experimental evaluations show the performance gains of the formant tracking, pitch extraction and noise reduction stages.