Punita Singh - Profile on Academia.edu (original) (raw)
Papers by Punita Singh
Pitching timbre analogies with David Wessel
The Journal of the Acoustical Society of America, 2017
Contemporary thinking and research on timbre and its use as a dynamic, structural component in mu... more Contemporary thinking and research on timbre and its use as a dynamic, structural component in music performance have been profoundly influenced by the insights and insounds of David Wessel. His intrepid and creative approach opened up vistas of timbre spaces navigable through multidimensional trajectories. Wessel’s experiments with timbre streaming [Computer Music J. 3, 4552, (1979)] inspired my own work on perceptual organization of complex-tone sequences [Singh, J. Acoust. Soc. Am. 82, 886-899 (1987)]. The finding of a timbre “interva” akin to a pitch interval as a threshold for streaming reinforced Wessel’s notion of timbral analogies [Ehresman and Wessel, IRCAM Rep 13/78, (1978)]. Later work on measuring timbre differences through FO thresholds for streaming (Singh and Bregman, J. Acoust. Soc. Am. 102(4), 1943-1952, (1997)) also lent support to the idea of intervallic relationship between timbres. More recently, my work relating Auditory Scene Analysis to Hindustani rhythms bro...
Spectral locus and spectral spacing as determinants of the perceptual organization of complex tone sequences
The Journal of the Acoustical Society of America, 1985
The perceptual organization of complex tone sequences into subsequences or “streams” was studied ... more The perceptual organization of complex tone sequences into subsequences or “streams” was studied using spectral differences between tones as a basis for eliciting segregation. The absolute position of the spectra was varied to provide timbral differences between tones, while relative spacing between harmonics was varied to provide differences in pitch. These attributes were put in competition in rapidly occurring sequences of the form: TxPx TyPx TxPy TyPy, with the first pair of tones being assigned the pitch Px but different timbres Tx and Ty, and the second pair pitch Py, and similarly different timbres. Six listeners indicated their percept of such sequences as being groupings based on timbral similarity, pitch proximity, or ambiguous patterns not dominated by either cue. The results demonstrated that the stream segregation phenomenon may be based on relative changes in spectral locus and spectral spacing of the sequential tones, and imply that timbre and pitch can both serve as ...
Parsing complex rhythmic structures: The contribution of spectral and temporal dimensions of timbre
The Journal of the Acoustical Society of America, 1999
Perceptual parsing of sequences with multiple possible metric interpretations was studied. Sequen... more Perceptual parsing of sequences with multiple possible metric interpretations was studied. Sequences of 12 complex tones were used as stimuli, with either no deliberate accents provided, or physical accents introduced by changing timbre at positions implying a triple, quadruple, or multiple meter (i.e., both triple and quadruple simultaneously). Subjects reported if they perceived a triple meter, quadruple meter, ambiguous meter, or no meter. The number of harmonics (2, 4, or 8) or the locus of three harmonics were the spectral variables used to mark timbre accents. Steepness of rise and decay time (95+5 ms versus 5+95 ms) was the temporal variable used. These attributes served well as accent markers for sequences with unambiguous meters. However, listeners were generally unable to parse sequences where multiple meters were provided by the same timbre cue. For sequences where multiple meters were provided by contrasting timbres, listeners generally picked the metrical structure impl...
The role of timbre, pitch, and loudness changes in determining perceived metrical structure
The Journal of the Acoustical Society of America, 1997
The role of differences in pitch, loudness, and timbre as determinants of metrical structures was... more The role of differences in pitch, loudness, and timbre as determinants of metrical structures was investigated. A repeated sequence of 12 pure tones was systematically partitioned into 4 groups of 3 tones or 3 groups of 4 tones by introducing changes in F0, intensity, and spectral complexity between sounds at serial positions 1, 4, 7, 10 or 1, 5, 9, respectively. Listeners used a rating scale to indicate if a triple, quadruple, or ambiguous meter was perceived. For changes in only one parameter at a time, perception of rhythmic structure followed the physical markers. When changes in more than one parameter were made concurrently, multiple cues for triple or quadruple meter were available. Coincident changes led to reinforcement of the rhythm demarcated by the points of change. Conflicting changes led to different outcomes: Timbre and pitch changes dominated over a loudness-based accent structure. Pitch versus timbre stimuli were rated as having ambiguous meter. A combination of any...
An investigation of different timbral attributes as markers determining metrical structure
The Journal of the Acoustical Society of America, 1998
Timbre attributes such as spectral locus, spectral density, and temporal envelope slope were stud... more Timbre attributes such as spectral locus, spectral density, and temporal envelope slope were studied to determine their relative effectiveness as accent markers defining metrical structure. Complex-tone sequences comprising 12 tones were used as stimuli with points of timbre change at positions implying a triple meter, quadruple meter, compound meter (both triple and quadruple), or unaccented sequences with no timbre changes. Tones at accented positions were made to differ from the rest by using different spectral densities (1, 2, 4, or 8 harmonic components), by changing the locus of components, and by changing the slopes of a two-part temporal amplitude envelope. Listeners were asked to report if the sequence had a triple meter, quadruple meter, ambiguous meter, or no meter. Results thus far indicate that each of the timbre markers used is individually capable of bestowing metrical structure on a sequence. However, when competing cues exist to offer alternative interpretations of ...
Transcending boundaries with Ira Hirsh
The Journal of the Acoustical Society of America, 2002
Ira Hirsh has made many contributions to various fields of acoustics from speech, hearing, psycho... more Ira Hirsh has made many contributions to various fields of acoustics from speech, hearing, psychological and physiological acoustics, to musical and architectural acoustics. It was a privilege for me to have been his student in all these areas, and to have had him as a guide through masters and doctoral degree programs that focused on topics that lie at the boundaries connecting these disciplines. Ira was not a prescriptive advisor, imposing particular research topics or procedures on his graduate students. Rather, he encouraged originality, innovation, and personal goal setting. He would subtly suggest starting points and provide landmarks as references, rather than explicit directions leading to them. One had to navigate the path by ones own wits. This approach encouraged lateral, out-of-the box thinking, while also leading to respectful appreciation of historic trajectories in scientific research. During our time together, we worked on several aspects of music, including, rhythm,...
Analysis of rhythm performance strategies on the Indian tabla as a function of tempo
The Journal of the Acoustical Society of America, 2012
In north Indian classical music, the range of tempi can extend from the ultra-slow ‘vilambit’ at ... more In north Indian classical music, the range of tempi can extend from the ultra-slow ‘vilambit’ at less than a beat every 5 seconds to the super-fast ‘drut’ at over 10 beats per second. To hold a rhythm at these speeds and generate a perceptible metrical structure, performers routinely alter playing strategies that derive from neurophysiological and psychoacoustical considerations. At slow speeds, theoretically silent intervals are in practice punctuated by filler sounds to maintain perceptual connectivity. At high speeds, an interesting phenomenon is observed as compound sounds or ‘bols’ segregate into their simpler components, forming auditory streams of acoustically similar sounds. Compound bols such as ‘dha’ break up into the tonal ‘ta’ and the noisy ‘ghe’, with the sequence of rapidly recurring ‘ghe’ sounds forming a noise band that could potentially mask tonal accent markers. To avoid this, performers routinely drop out the ‘ghe’ sounds at high speeds at metrically unimportant p...
The Journal of the Acoustical Society of America, 1987
Sequences of rapidly occurring sounds that differ from each other are often perceptually segregat... more Sequences of rapidly occurring sounds that differ from each other are often perceptually segregated into ‘‘streams’’ within which the range of differences is smaller [Bregman and Campbell, J. Exp. Psychol. 89, 244–249 (1971)]. Early research on streaming implied it to be pitch dominated, but Wessel [Comput. Music J. 3, 45–52 (1979)] demonstrated that timbre differences could also bring about segregation. In the present study, pitch and timbre attributes were put in competition in four-tone sequences of the form: T2P1-TmP1-T2Pn-TmPn, with the first pair assigned pitch P1 but different timbres T2 and Tm, and the second pair pitch Pn, and similarly contrasted timbres. Six listeners were asked to indicate whether perceived grouping of 49 such sequences was based on pitch proximity, timbre similarity, or ambiguous percepts not dominated by either cue. Results confirm that timbre can segregate sequences and imply that timbre and pitch compete in perceptually organizing complex sequences. ...
Perception of rhythm by children in multitimbral, multimetric contexts
The Journal of the Acoustical Society of America, 1999
Perception of meter by children aged 6 to 12 was studied using sequences of 12 tones as stimuli. ... more Perception of meter by children aged 6 to 12 was studied using sequences of 12 tones as stimuli. Either no accents, or physical accents at positions implying triple, quadruple, or both meters were provided by changing the spectral locus of four harmonics n, n+1, n+2, n=3, of tones Ln (where n=2 or 6) or the rise/decay times of their temporal envelopes (95+5 ms, vs 5+95 ms). Listeners reported if they perceived a triple, quadruple, or ambiguous meter, or no accents at all. Children were easily able to perceive the metrical structure of sequences with accents on triple or quadruple meter positions alone. Mixed meters were hard to parse in a single-timbre context. In mixed sequences with accents provided by different timbre features at quadruple and triple meter positions, listeners tended to follow the meter implied by tones L2 rather than L6. Temporal envelope variables were not effective in facilitating parsing of mixed meters. Results indicate that young listeners are similar to ad...
The Journal of the Acoustical Society of America, 1986
The acoustical characteristics of music practice facilities are compared with those of some perfo... more The acoustical characteristics of music practice facilities are compared with those of some performance halls available at a university campus. Glaring quantifiable differences are observed between the practice spaces and performance spaces in terms of size, shape, reverberation, and interior construction schemes. Furthermore, the Perceived acoustical qualities of three performance spaces studied also vary greatly from each other, one being popularly referred to as “very reverberant and muddy,” another “dead,” and a third, “good.” The physical differences observed are presented, and their effect on the performance of music rehearsed in the small practice facilities and performed in the larger auditoria considered via subjective reports made by performers and listeners. These observations are further supplemented by an account of strategies employed by performers in adapting production to suit the different spaces, to compensate for the “transition loss” incurred in going from the pr...
The traditionally maintained separateness of" timbre" from other tonal percepts such as... more The traditionally maintained separateness of" timbre" from other tonal percepts such as" pitch" is questioned in a set of experiments designed to ascertain perceptual cues facilitating auditory discrimination tasks. Three types of complex sounds with flat spectral ...
The Journal of the Acoustical Society of America, 1989
The dual nature of pitch (“spectral”/“virtual”) and its relation to such timbral percepts as “sha... more The dual nature of pitch (“spectral”/“virtual”) and its relation to such timbral percepts as “sharpness” and “roughness” is explored in a set of experiments designed to ascertain perceptual cues facilitating discrimination tasks with complex tones having flat spectral envelopes. Three types of complexes are employed: (1) harmonic “residue” tones comprising four harmonics, (2) ten-component harmonic and inharmonic complexes with all components shifted from some reference frequency, and (3) ten-component complexes with a single component shifted from its harmonic frequency. Using two-tone sequences as stimuli, listeners are asked to judge if the second tone is (1) the same, (2) higher in pitch, (3) lower in pitch, (4) different in “something else,” (5) different in “something else” and higher, or (6) diffferent in “something else” and lower in pitch than the first (“something else” is taken to be synonymous with “timbre”). For residue tones, data indicate that changes in spectral locu...
Journal of the Acoustical Society of America, Nov 1, 1989
Journal of the Acoustical Society of America, Apr 1, 1991
Journal of the Acoustical Society of America, Apr 1, 1985
The contribution of spectrum and tempo to auditory streaming of simple and compound “bols” in tabla rhythms
Journal of the Acoustical Society of America, Nov 1, 2013
Rhythms on the tabla, a north Indian percussion instrument, are generated by producing sounds on ... more Rhythms on the tabla, a north Indian percussion instrument, are generated by producing sounds on one or two drums separately or simultaneously to produce simple or compound “bols.” At high speeds, auditory stream segregation based on spectral properties of adjacent bols can create parallel perceptual layers that can be leveraged strategically by percussionists. This observed phenomenon was studied experimentally by constructing sequences of bols in which adjacent sounds shared different spectral regions. For example, the bols “ghe” and “tin,” which have very different spectra, were placed on either side of the compound bol “dhin,” which contains both “ghe” and “tin.” At a moderate tempo, the sequence is typically heard as a gallop rhythm. However, at quicker tempi, streaming occurs and components of the compound bol “dhin” group perceptually with their neighboring counterparts, to create parallel layers of pairs of “ghe,” “ghe” and “tin,” “tin”, instead of the galloping triple. Listeners identified when streaming took place as a function of the specific bols and tempi used. Spectral analyses of the bols indicated that perceptual segregation was indeed based on proximity of spectral loci. At high speeds, spectral differences are perceptually highlighted and facilitate the formation of auditory streams.
Spectro‐temporal factors in the perceptual segregation of tonal sequences
Journal of the Acoustical Society of America, Apr 1, 1993
Spectral factors such as differences in harmonic content are powerful cues in the organization of... more Spectral factors such as differences in harmonic content are powerful cues in the organization of tonal sequences. Temporal factors such as rise time, however, have been shown to be poor cues [W. M. Hartmann and D. Johnson, Mus. Perc. 9(2), 155–184 (1991)]. The relative salience of these factors was investigated further using complex tones sequenced in a repeating ABA-‘‘gallop’’ format, under conditions in which tones A and B had the same, or different harmonic content and/or temporal envelope shape. The F0 difference between A and B was initially 0 Hz, but increased over the course of a trial, until terminated by a listener, indicating perceptual segregation of the input sequence into sub-sequences comprising A and B tones, respectively. The F0 difference required to reach this segregation threshold provided a measure of the efficacy of stimulus features of A and B as cues for sequential organization. Sequences combining differences in spectral content and temporal envelope shape required the smallest F0 change for segregation. Sequences of tones with the same harmonic structure and temporal envelope required the largest F0 changes, while the other conditions fell in the middle of this range. Results will be discussed in terms of implications for sequential organization as well as for the perception of timbre. [Work supported by NSERC, Canada.]
Proceedings of Meetings on Acoustics, 2013
The use of 'chikari' strings on instruments such as the sitar and sarod manifests principles of A... more The use of 'chikari' strings on instruments such as the sitar and sarod manifests principles of Auditory Scene Analysis in creating a harmonic reference, melodic contrast and rhythmic accompaniment. Unlike the principal 'baj' strings on which the main melody is played, or resonant 'tarb' strings that reinforce volume, the 'chikari' strings are sounded at strategic points in performance to provide a drone, add texture, outline chords, mark rhythmic positions and keep tempo. Listening and transcription experiments conducted with recordings of interleaved notes played on 'chikari' and 'baj' strings validate how differences in their timbre and tuning help to keep them perceptually apart while forming more coherent patterns based on timbre similarity and pitch proximity. Such grouping and segregation can affect the perception of temporal order, maintain the illusion of melodic continuity and in some cases of virtual polyphony. These observations add to the growing body of evidence supporting the role of timbre as a structural dimension of music and illustrate how a single instrument can bring about orchestral effects via the strategic use of devices such as 'chikari' strings.
Journal of the Acoustical Society of America, Oct 1, 1997
Spectral factors such as differences in harmonic content are powerful cues in the perceptual orga... more Spectral factors such as differences in harmonic content are powerful cues in the perceptual organization of tone sequences. Temporal features such as rise time, however, have been shown to be poor cues ͓W. M. Hartmann and D. Johnson, Mus. Perc. 9, 155-184 ͑1991͔͒. The relative influence of these timbral features on perceptual segregation was investigated. Complex tones were sequenced in a repeating ABA-''gallop'' format, under four conditions in which tones A and B had the same or different timbres as defined by differences in numbers of harmonics and temporal-envelope features. A sequence started with A and B tones at the same F0. The F0 difference between A and B then increased over the course of a trial, until a listener terminated the trial indicating perceptual segregation into sub-sequences comprising A and B tones, respectively. The F0 difference required to reach this crossover point of segregation provided a measure of the efficacy of stimulus features of A and B as cues for perceptual organization. Sequences combining differences in harmonic structure and temporal envelope required the smallest F0 change for segregation. Sequences of tones with the same harmonic structure and temporal envelope required larger changes in F0, while the other conditions fell in the middle of this range. The F0-tracking method used in this study facilitates measurement of the relative contribution of different stimulus features to stream segregation. It also holds potential as a tool using the point of segregation as a measure of the magnitude of timbre differences brought about by different physical features of sounds.
Journal of the Acoustical Society of America, Apr 1, 1992
Pitching timbre analogies with David Wessel
The Journal of the Acoustical Society of America, 2017
Contemporary thinking and research on timbre and its use as a dynamic, structural component in mu... more Contemporary thinking and research on timbre and its use as a dynamic, structural component in music performance have been profoundly influenced by the insights and insounds of David Wessel. His intrepid and creative approach opened up vistas of timbre spaces navigable through multidimensional trajectories. Wessel’s experiments with timbre streaming [Computer Music J. 3, 4552, (1979)] inspired my own work on perceptual organization of complex-tone sequences [Singh, J. Acoust. Soc. Am. 82, 886-899 (1987)]. The finding of a timbre “interva” akin to a pitch interval as a threshold for streaming reinforced Wessel’s notion of timbral analogies [Ehresman and Wessel, IRCAM Rep 13/78, (1978)]. Later work on measuring timbre differences through FO thresholds for streaming (Singh and Bregman, J. Acoust. Soc. Am. 102(4), 1943-1952, (1997)) also lent support to the idea of intervallic relationship between timbres. More recently, my work relating Auditory Scene Analysis to Hindustani rhythms bro...
Spectral locus and spectral spacing as determinants of the perceptual organization of complex tone sequences
The Journal of the Acoustical Society of America, 1985
The perceptual organization of complex tone sequences into subsequences or “streams” was studied ... more The perceptual organization of complex tone sequences into subsequences or “streams” was studied using spectral differences between tones as a basis for eliciting segregation. The absolute position of the spectra was varied to provide timbral differences between tones, while relative spacing between harmonics was varied to provide differences in pitch. These attributes were put in competition in rapidly occurring sequences of the form: TxPx TyPx TxPy TyPy, with the first pair of tones being assigned the pitch Px but different timbres Tx and Ty, and the second pair pitch Py, and similarly different timbres. Six listeners indicated their percept of such sequences as being groupings based on timbral similarity, pitch proximity, or ambiguous patterns not dominated by either cue. The results demonstrated that the stream segregation phenomenon may be based on relative changes in spectral locus and spectral spacing of the sequential tones, and imply that timbre and pitch can both serve as ...
Parsing complex rhythmic structures: The contribution of spectral and temporal dimensions of timbre
The Journal of the Acoustical Society of America, 1999
Perceptual parsing of sequences with multiple possible metric interpretations was studied. Sequen... more Perceptual parsing of sequences with multiple possible metric interpretations was studied. Sequences of 12 complex tones were used as stimuli, with either no deliberate accents provided, or physical accents introduced by changing timbre at positions implying a triple, quadruple, or multiple meter (i.e., both triple and quadruple simultaneously). Subjects reported if they perceived a triple meter, quadruple meter, ambiguous meter, or no meter. The number of harmonics (2, 4, or 8) or the locus of three harmonics were the spectral variables used to mark timbre accents. Steepness of rise and decay time (95+5 ms versus 5+95 ms) was the temporal variable used. These attributes served well as accent markers for sequences with unambiguous meters. However, listeners were generally unable to parse sequences where multiple meters were provided by the same timbre cue. For sequences where multiple meters were provided by contrasting timbres, listeners generally picked the metrical structure impl...
The role of timbre, pitch, and loudness changes in determining perceived metrical structure
The Journal of the Acoustical Society of America, 1997
The role of differences in pitch, loudness, and timbre as determinants of metrical structures was... more The role of differences in pitch, loudness, and timbre as determinants of metrical structures was investigated. A repeated sequence of 12 pure tones was systematically partitioned into 4 groups of 3 tones or 3 groups of 4 tones by introducing changes in F0, intensity, and spectral complexity between sounds at serial positions 1, 4, 7, 10 or 1, 5, 9, respectively. Listeners used a rating scale to indicate if a triple, quadruple, or ambiguous meter was perceived. For changes in only one parameter at a time, perception of rhythmic structure followed the physical markers. When changes in more than one parameter were made concurrently, multiple cues for triple or quadruple meter were available. Coincident changes led to reinforcement of the rhythm demarcated by the points of change. Conflicting changes led to different outcomes: Timbre and pitch changes dominated over a loudness-based accent structure. Pitch versus timbre stimuli were rated as having ambiguous meter. A combination of any...
An investigation of different timbral attributes as markers determining metrical structure
The Journal of the Acoustical Society of America, 1998
Timbre attributes such as spectral locus, spectral density, and temporal envelope slope were stud... more Timbre attributes such as spectral locus, spectral density, and temporal envelope slope were studied to determine their relative effectiveness as accent markers defining metrical structure. Complex-tone sequences comprising 12 tones were used as stimuli with points of timbre change at positions implying a triple meter, quadruple meter, compound meter (both triple and quadruple), or unaccented sequences with no timbre changes. Tones at accented positions were made to differ from the rest by using different spectral densities (1, 2, 4, or 8 harmonic components), by changing the locus of components, and by changing the slopes of a two-part temporal amplitude envelope. Listeners were asked to report if the sequence had a triple meter, quadruple meter, ambiguous meter, or no meter. Results thus far indicate that each of the timbre markers used is individually capable of bestowing metrical structure on a sequence. However, when competing cues exist to offer alternative interpretations of ...
Transcending boundaries with Ira Hirsh
The Journal of the Acoustical Society of America, 2002
Ira Hirsh has made many contributions to various fields of acoustics from speech, hearing, psycho... more Ira Hirsh has made many contributions to various fields of acoustics from speech, hearing, psychological and physiological acoustics, to musical and architectural acoustics. It was a privilege for me to have been his student in all these areas, and to have had him as a guide through masters and doctoral degree programs that focused on topics that lie at the boundaries connecting these disciplines. Ira was not a prescriptive advisor, imposing particular research topics or procedures on his graduate students. Rather, he encouraged originality, innovation, and personal goal setting. He would subtly suggest starting points and provide landmarks as references, rather than explicit directions leading to them. One had to navigate the path by ones own wits. This approach encouraged lateral, out-of-the box thinking, while also leading to respectful appreciation of historic trajectories in scientific research. During our time together, we worked on several aspects of music, including, rhythm,...
Analysis of rhythm performance strategies on the Indian tabla as a function of tempo
The Journal of the Acoustical Society of America, 2012
In north Indian classical music, the range of tempi can extend from the ultra-slow ‘vilambit’ at ... more In north Indian classical music, the range of tempi can extend from the ultra-slow ‘vilambit’ at less than a beat every 5 seconds to the super-fast ‘drut’ at over 10 beats per second. To hold a rhythm at these speeds and generate a perceptible metrical structure, performers routinely alter playing strategies that derive from neurophysiological and psychoacoustical considerations. At slow speeds, theoretically silent intervals are in practice punctuated by filler sounds to maintain perceptual connectivity. At high speeds, an interesting phenomenon is observed as compound sounds or ‘bols’ segregate into their simpler components, forming auditory streams of acoustically similar sounds. Compound bols such as ‘dha’ break up into the tonal ‘ta’ and the noisy ‘ghe’, with the sequence of rapidly recurring ‘ghe’ sounds forming a noise band that could potentially mask tonal accent markers. To avoid this, performers routinely drop out the ‘ghe’ sounds at high speeds at metrically unimportant p...
The Journal of the Acoustical Society of America, 1987
Sequences of rapidly occurring sounds that differ from each other are often perceptually segregat... more Sequences of rapidly occurring sounds that differ from each other are often perceptually segregated into ‘‘streams’’ within which the range of differences is smaller [Bregman and Campbell, J. Exp. Psychol. 89, 244–249 (1971)]. Early research on streaming implied it to be pitch dominated, but Wessel [Comput. Music J. 3, 45–52 (1979)] demonstrated that timbre differences could also bring about segregation. In the present study, pitch and timbre attributes were put in competition in four-tone sequences of the form: T2P1-TmP1-T2Pn-TmPn, with the first pair assigned pitch P1 but different timbres T2 and Tm, and the second pair pitch Pn, and similarly contrasted timbres. Six listeners were asked to indicate whether perceived grouping of 49 such sequences was based on pitch proximity, timbre similarity, or ambiguous percepts not dominated by either cue. Results confirm that timbre can segregate sequences and imply that timbre and pitch compete in perceptually organizing complex sequences. ...
Perception of rhythm by children in multitimbral, multimetric contexts
The Journal of the Acoustical Society of America, 1999
Perception of meter by children aged 6 to 12 was studied using sequences of 12 tones as stimuli. ... more Perception of meter by children aged 6 to 12 was studied using sequences of 12 tones as stimuli. Either no accents, or physical accents at positions implying triple, quadruple, or both meters were provided by changing the spectral locus of four harmonics n, n+1, n+2, n=3, of tones Ln (where n=2 or 6) or the rise/decay times of their temporal envelopes (95+5 ms, vs 5+95 ms). Listeners reported if they perceived a triple, quadruple, or ambiguous meter, or no accents at all. Children were easily able to perceive the metrical structure of sequences with accents on triple or quadruple meter positions alone. Mixed meters were hard to parse in a single-timbre context. In mixed sequences with accents provided by different timbre features at quadruple and triple meter positions, listeners tended to follow the meter implied by tones L2 rather than L6. Temporal envelope variables were not effective in facilitating parsing of mixed meters. Results indicate that young listeners are similar to ad...
The Journal of the Acoustical Society of America, 1986
The acoustical characteristics of music practice facilities are compared with those of some perfo... more The acoustical characteristics of music practice facilities are compared with those of some performance halls available at a university campus. Glaring quantifiable differences are observed between the practice spaces and performance spaces in terms of size, shape, reverberation, and interior construction schemes. Furthermore, the Perceived acoustical qualities of three performance spaces studied also vary greatly from each other, one being popularly referred to as “very reverberant and muddy,” another “dead,” and a third, “good.” The physical differences observed are presented, and their effect on the performance of music rehearsed in the small practice facilities and performed in the larger auditoria considered via subjective reports made by performers and listeners. These observations are further supplemented by an account of strategies employed by performers in adapting production to suit the different spaces, to compensate for the “transition loss” incurred in going from the pr...
The traditionally maintained separateness of" timbre" from other tonal percepts such as... more The traditionally maintained separateness of" timbre" from other tonal percepts such as" pitch" is questioned in a set of experiments designed to ascertain perceptual cues facilitating auditory discrimination tasks. Three types of complex sounds with flat spectral ...
The Journal of the Acoustical Society of America, 1989
The dual nature of pitch (“spectral”/“virtual”) and its relation to such timbral percepts as “sha... more The dual nature of pitch (“spectral”/“virtual”) and its relation to such timbral percepts as “sharpness” and “roughness” is explored in a set of experiments designed to ascertain perceptual cues facilitating discrimination tasks with complex tones having flat spectral envelopes. Three types of complexes are employed: (1) harmonic “residue” tones comprising four harmonics, (2) ten-component harmonic and inharmonic complexes with all components shifted from some reference frequency, and (3) ten-component complexes with a single component shifted from its harmonic frequency. Using two-tone sequences as stimuli, listeners are asked to judge if the second tone is (1) the same, (2) higher in pitch, (3) lower in pitch, (4) different in “something else,” (5) different in “something else” and higher, or (6) diffferent in “something else” and lower in pitch than the first (“something else” is taken to be synonymous with “timbre”). For residue tones, data indicate that changes in spectral locu...
Journal of the Acoustical Society of America, Nov 1, 1989
Journal of the Acoustical Society of America, Apr 1, 1991
Journal of the Acoustical Society of America, Apr 1, 1985
The contribution of spectrum and tempo to auditory streaming of simple and compound “bols” in tabla rhythms
Journal of the Acoustical Society of America, Nov 1, 2013
Rhythms on the tabla, a north Indian percussion instrument, are generated by producing sounds on ... more Rhythms on the tabla, a north Indian percussion instrument, are generated by producing sounds on one or two drums separately or simultaneously to produce simple or compound “bols.” At high speeds, auditory stream segregation based on spectral properties of adjacent bols can create parallel perceptual layers that can be leveraged strategically by percussionists. This observed phenomenon was studied experimentally by constructing sequences of bols in which adjacent sounds shared different spectral regions. For example, the bols “ghe” and “tin,” which have very different spectra, were placed on either side of the compound bol “dhin,” which contains both “ghe” and “tin.” At a moderate tempo, the sequence is typically heard as a gallop rhythm. However, at quicker tempi, streaming occurs and components of the compound bol “dhin” group perceptually with their neighboring counterparts, to create parallel layers of pairs of “ghe,” “ghe” and “tin,” “tin”, instead of the galloping triple. Listeners identified when streaming took place as a function of the specific bols and tempi used. Spectral analyses of the bols indicated that perceptual segregation was indeed based on proximity of spectral loci. At high speeds, spectral differences are perceptually highlighted and facilitate the formation of auditory streams.
Spectro‐temporal factors in the perceptual segregation of tonal sequences
Journal of the Acoustical Society of America, Apr 1, 1993
Spectral factors such as differences in harmonic content are powerful cues in the organization of... more Spectral factors such as differences in harmonic content are powerful cues in the organization of tonal sequences. Temporal factors such as rise time, however, have been shown to be poor cues [W. M. Hartmann and D. Johnson, Mus. Perc. 9(2), 155–184 (1991)]. The relative salience of these factors was investigated further using complex tones sequenced in a repeating ABA-‘‘gallop’’ format, under conditions in which tones A and B had the same, or different harmonic content and/or temporal envelope shape. The F0 difference between A and B was initially 0 Hz, but increased over the course of a trial, until terminated by a listener, indicating perceptual segregation of the input sequence into sub-sequences comprising A and B tones, respectively. The F0 difference required to reach this segregation threshold provided a measure of the efficacy of stimulus features of A and B as cues for sequential organization. Sequences combining differences in spectral content and temporal envelope shape required the smallest F0 change for segregation. Sequences of tones with the same harmonic structure and temporal envelope required the largest F0 changes, while the other conditions fell in the middle of this range. Results will be discussed in terms of implications for sequential organization as well as for the perception of timbre. [Work supported by NSERC, Canada.]
Proceedings of Meetings on Acoustics, 2013
The use of 'chikari' strings on instruments such as the sitar and sarod manifests principles of A... more The use of 'chikari' strings on instruments such as the sitar and sarod manifests principles of Auditory Scene Analysis in creating a harmonic reference, melodic contrast and rhythmic accompaniment. Unlike the principal 'baj' strings on which the main melody is played, or resonant 'tarb' strings that reinforce volume, the 'chikari' strings are sounded at strategic points in performance to provide a drone, add texture, outline chords, mark rhythmic positions and keep tempo. Listening and transcription experiments conducted with recordings of interleaved notes played on 'chikari' and 'baj' strings validate how differences in their timbre and tuning help to keep them perceptually apart while forming more coherent patterns based on timbre similarity and pitch proximity. Such grouping and segregation can affect the perception of temporal order, maintain the illusion of melodic continuity and in some cases of virtual polyphony. These observations add to the growing body of evidence supporting the role of timbre as a structural dimension of music and illustrate how a single instrument can bring about orchestral effects via the strategic use of devices such as 'chikari' strings.
Journal of the Acoustical Society of America, Oct 1, 1997
Spectral factors such as differences in harmonic content are powerful cues in the perceptual orga... more Spectral factors such as differences in harmonic content are powerful cues in the perceptual organization of tone sequences. Temporal features such as rise time, however, have been shown to be poor cues ͓W. M. Hartmann and D. Johnson, Mus. Perc. 9, 155-184 ͑1991͔͒. The relative influence of these timbral features on perceptual segregation was investigated. Complex tones were sequenced in a repeating ABA-''gallop'' format, under four conditions in which tones A and B had the same or different timbres as defined by differences in numbers of harmonics and temporal-envelope features. A sequence started with A and B tones at the same F0. The F0 difference between A and B then increased over the course of a trial, until a listener terminated the trial indicating perceptual segregation into sub-sequences comprising A and B tones, respectively. The F0 difference required to reach this crossover point of segregation provided a measure of the efficacy of stimulus features of A and B as cues for perceptual organization. Sequences combining differences in harmonic structure and temporal envelope required the smallest F0 change for segregation. Sequences of tones with the same harmonic structure and temporal envelope required larger changes in F0, while the other conditions fell in the middle of this range. The F0-tracking method used in this study facilitates measurement of the relative contribution of different stimulus features to stream segregation. It also holds potential as a tool using the point of segregation as a measure of the magnitude of timbre differences brought about by different physical features of sounds.
Journal of the Acoustical Society of America, Apr 1, 1992