bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement repeatability of late lateral energy level and lateral energy fraction
Authors: Dick David A. , Vigeant Michelle C.
Published: May 2014

Late lateral energy level (GLL) and lateral energy fraction (LF) are two room acoustics measures that have been shown to correlate with certain aspects of spatial impression in concert halls. The purpose of this study was to investigate the repeatability of GLL and LF measurements. A custom microphone stand was built that can be adjusted in each spatial dimension separately to allow for accurate and precise microphone placement. Room impulse responses (IRs) were measured at six receiver locations in a 2500-seat auditorium using two different methods to obtain the lateral energy IR: the beamformed dipole response from a spherical microphone array, and a studio-grade figure-of-eight microphone. Three sets of IR measurements were taken at each receiver location. In between sets, the microphone stand was removed and the various adjustment points were randomly repositioned. The stand was then replaced in the same position to re-measure the IRs. The variability between the measurements at each receiver location was found to be relatively low for GLL (the standard deviation ranged between 0.22 and 0.73 JNDs for the 125–1000 Hz sum), and higher for LF (the standard deviation ranged between 0.49 and 2.80 JNDs for the average over the 125–1000 Hz octave bands). [Work supported by NSF Grant 1302741.]
Uncertainty in room acoustics: A consultant's perspective
Authors: Markham Benjamin , Sacks Jonah
Published: May 2014

Faced with time and budget constraints on most projects, acoustical consultants make a series of choices when asked to evaluate the acoustics of an existing space. Measure the impulse response of the room with sophisticated technology (MLS, sine-sweeps, etc.), or pop a balloon? Use a dodecahedral loudspeaker (or several), a more standard portable amplified loudspeaker, or the house sound system (or pop a balloon)? Use a single omni-directional microphone, a binaural dummy head, or a B-format soundfield microphone? How many source locations, and how many receiver locations? Whither measure? There is a growing body of literature that identifies uncertainty and inconsistency in reverberation time and other room acoustics metrics and the tools used to obtain them. The authors will add modestly to this evidence from consulting experience, and then focus on how some consultants in architectural acoustics choose what data to gather, how to gather it, and to what extent. Considerations of time, budget, and logistics factor in those choices, as do determinations regarding the essence of the client's needs and concerns, subjective listening to determine what measurements could be most useful, and our own expectations for how we might use the measurements we make, now and in the future.
A closer look at the Hopkins-Stryker equation
Authors: Leishman Timothy W. , Jensen Zachary R.
Published: May 2014

The Hopkins-Stryker equation has long been used to represent sound fields in semi-reverberant rooms. However, its implementation could be improved if users were more familiar with its origins, assumptions, and potential applications. The directivity factor, distance from the acoustic center, room constant, and locally averaged energy density are all key elements of the equation that merit special attention. This presentation explores these quantities and their theoretical underpinnings. It also introduces the use of generalized energy density as a means of simplifying averaging requirements. Selected numerical examples serve as illustrations to clarify the concepts.
Sources of acoustic variation in the advertisement vocalizations of Neotropical singing mice
Authors: Pasch Bret , Campbell Polly , Abbasi Mustafa Z. , Wilson Preston S. , Phelps Steven M. , Ryan Michael J.
Published: May 2014

Patterns of variation in communication systems provide important insight into the processes that shape phenotypic evolution. Although studies in anurans, birds, and insects indicate that diverse selective and stochastic forces influence acoustic signals, factors that shape variation in mammalian vocalizations are poorly understood. Neotropical singing mice (Scotinomys) are diurnal, insectivorous rodents distributed throughout montane cloud forests of Middle America. Males commonly emit species-specific advertisement vocalizations that are used in mate attraction and male-male aggression. To explore factors contributing to vocal variation, we summarize data from a diversity of studies at disparate scales and levels of analysis. We highlight the importance of genetic drift in shaping population differentiation, the role of androgens in modulating the performance of physically challenging displays, the influence of social context in shaping posture and vocal parameters, and the impact of the ambient environment in affecting sound propagation. Neotropical singing mice are emerging as an important model that enables us to draw parallels to vocal communication systems in traditionally more tractable species.
Using passive acoustics to investigate seasonal and diel trends in acoustic behavior of North Atlantic right whales (Eubalaena glacialis)
Authors: Matthews Leanna P. , McCordic Jessica A. , Parks Susan E.
Published: May 2014

The North Atlantic right whale (Eubalaena glacialis), an endangered baleen whale species, produces a variety of stereotyped acoustic signals. One signal, the “gunshot” sound, has only been recorded from adult males and is thought to function for reproduction, either as advertisement for females or an agonistic signal toward other males. This study uses remote acoustic monitoring to analyze the presence of gunshots over a two-year period at two sites on the Scotian Shelf to determine if there is evidence that right whales use these locations for breeding activities. Seasonal analyses at both locations indicate that gunshot production is highly seasonal, with an increase in autumn. One site had significantly more gunshot sounds and exhibited a clear diel trend in signal production. The other site also showed a seasonal increase during autumn, but did not show any significant diel trends. This site difference indicates variation either in the number or the behavior of whales at each location. The timing of the observed seasonality in gunshot production is consistent with the current understanding of right whale breeding season, and these results demonstrate that detection of gunshots with remote acoustic monitoring can be a reliable way to track seasonal mating activities.
Counting odontocetes from click train detections using multiple independent autonomous acoustic sensors
Authors: Theriault James A. , Sheppard Craig , Hood Joey , Moors-Murphy Hilary B. , Coffin Matthew
Published: May 2014

Passive acoustic monitoring (PAM) is often suggested as an effective technology to mitigate impacts from anthropogenic activities; however, the ability to reliably and efficiently detect, locate, and count cetaceans using PAM is still in development. One particularly useful application of PAM is species density estimation, which requires an estimate of the number of individuals involved in a detection event. Efforts have been undertaken to develop methods to directly count the number of vocalizing animals during acoustic detection events. For odontocetes, discrete clicks are almost indistinguishable between individuals, making it more difficult to determine the number of vocalizing animals as the number increases. Using recordings from multiple closely spaced (≈200 m) GuardBuoy sensors deployed on the Canadian Scotian Shelf, cross-sensor correlograms were produced to estimate the number of individual sperm whales, and, as a more challenging case, the number of vocalizing delphinids. Using feature-based multipath reflection discrimination, the raw time series were reduced to a synthetic time series of binary click detections with the multipath arrivals removed. The synthesized click-detection time series were used for the cross-sensor correlograms to generate improved estimates of the number of vocalizing animals as compared with using the raw time series.
Excitation of multi-modes of vibration using tangentially polarized thin walled cylinders
Authors: Sarangapani Sairajan , Brown David A.
Published: May 2014

Tangentially polarized thin-walled striped-electroded piezoelectric cylindrical transducers are used in several electromechanical and electroacoustic applications. This study is an extension of the previous work [J. Acoust. Soc. Am. 133, 2661 (2013); J. Acoust. Soc. Am. 132, 3068 (2012)] and involves the study of electromechanical excitation of multi-modes of vibration using tangentially polarized cylinders. A numerical finite difference method (FDM) was used to analysis the nonuniform electric field in the tangentially polarized cylinder under the assumption that the piezoelectric element is fully polarized. The electromechanical properties including the effective electromechanical coupling coefficient, effective piezoelectric modulus, the effective compliance, and effective relative dielectric constant were calculated for a tangentially polarized cylinder for several modes of vibration and compared with results of cylinders using traditional transverse piezoelectric effect.
A micro-machined hydrophone based on piezoelectric-gate-of-field-effect-transistor for low frequency sounds detection
Authors: Sung Min , Shin Kumjae , Joh Cheeyoung , Moon Wonkyu
Published: May 2014

The miniaturization of conventional piezoelectric hydrophone is known to have limits in low frequencies due to high sensor impedance of micro-sized piezoelectric body. In this study, a new transduction mechanism is devised and named as piezoelectric gate of field effect transistor (PiGoFET) so that its application could solve the sensitivity limitation of a miniaturized hydrophone with a tiny piezoelectric body less than 1 mm. The PiGoFET transduction can be realized by combination of a field effect transistor and a small piezoelectric body on its gate. We connect a micro-machined membrane to the small piezoelectric body so that acoustic pressure can apply appropriate forces on the body on the FET gate. The electric field from the strained piezoelectric body modulates the channel current of FET at any frequency less than high limit of transistor; thus, the sound pressure may be transferred to the source-drain currents even at very low frequencies irrespective of the size of piezoelectric body. Under the described concept, a small hydrophone was fabricated by micromachining and calibrated using the comparison method in low frequencies to investigate its performance as a low frequency sensitive hydrophone. [Research funded by MRCnD.]
A survey of pipe organ reed research emphasizing recent developments
Authors: Plitnik George
Published: May 2014

As experimental and theoretical acoustics advanced during the 19th century several prominent researchers attempted, typically unsuccessfully, to understand the physics of pipe organ reeds. Centuries of organ building experience had advanced the art of reed voicing to a consummate skill passed down from masters to apprentices, with no understanding of, and no desire to learn, the underlying physical principles. This presentation will give a cursory survey of two centuries of organ reed investigations and then highlight the research during the past two decades which has unlocked some of the conundrums of the past to render these complicated instruments amenable to scientific understanding. The following reed parameters and their influence tone will be examined: reed thickness, reed length, imposed air pressure, reed curvature, shallot type, shallot filling, and the type of metal used for the reed as well as the provenance and method of its manufacture.
Construction issues affecting the intended acoustical environment of a new court tower
Authors: Brenneman Robert M.
Published: May 2014

The proficiency to readily identify and resolve construction issues in the field is vital to realizing intended acoustical design goals. In court facilities, inattention to such construction details can result in problematic reductions in speech privacy for confidential deliberations, negotiations, and attorney discussions, structure-borne noise intrusion from holding areas to noise-sensitive spaces, and diminished speech intelligibility in courtroom proceedings. This paper considers examples of acoustics and noise control issues arising during the construction of a new court tower, discussion of their potential effects on the acoustical environment, and methods of addressing these field conditions.
A potpourri of acoustical issues arising during construction administration
Authors: Bridger Joseph F. , Stewart Noral D.
Published: May 2014

This is a collection of our firm's most noteworthy experiences during construction administration. First, they illustrate the many ways what is built can go astray from what was recommended. In other cases, we do not get involved with the particular area of scope until construction administration. Sometimes in such cases, design professionals attempt to do acoustics themselves but lack the knowledge to do so correctly. At other times, design professionals are not even aware that an acoustics issue should be addressed, until it is noticed during construction. Of course, there is the contractor whom did not understand or simply did not do what the drawings and specifications called for. Lastly, there can simply be things that cannot/should not be built the way they were designed (often the contractor notices these things first) and the inevitable “now what do we do?” Of course anything that comes up during construction is on a short and critical time schedule, and fraught with the challenge of how to get things fixed quickly and with least added cost. It is our hope that these case studies will help building professionals and acoustical consultants on future projects.
Issues and opportunities during construction of a new courthouse building
Authors: Hoover K. Anthony
Published: May 2014

A new courthouse building was recently completed, housing 31 courtrooms and the full complement of ancillary spaces, and using a delivery system called performance-based infrastructure (PBI) that enhanced the need for high durability and long-term functionality, as well as a fast-paced schedule. An interesting issue arose concerning unexpectedly loud levels of toilet flush noise in a public restroom adjacent to a judge's chamber, whose resolution resulted in 20 dBA reduction at the source without need for reconstructed partitions in over a dozen similar adjacencies. An interesting opportunity arose when on opening day it was determined that a cueing room was noisy, and one of the architects emailed audio files of balloon pops recorded on his cell phone, in a manner that simulated measurements that he had witnessed several times before, and which confirmed our calculations sufficiently to engender agreement on treatment without need for additional site visits. These and perhaps other issues and opportunities will be discussed.
Method to improve warning sound detection for hearing protectors
Authors: Bernstein Eric , Brammer Anthony J. , Yu Gongqiang
Published: May 2014

Hearing protection devices (HPDs) provide both desirable attenuation of environmental noise and undesirable attenuation of auditory warning alarms, such as vehicle backup alarms. Both warning alarm detection and localization performance are affected. A digital cross-correlation based method is described to identify a pre-selected warning alarm to bypass the attenuation of the HPD while maintaining attenuation of environmental noise outside the bandwidth of the alarm. This method can be integrated into existing digital HPD designs. Computer simulation of the algorithm demonstrates that an alarm signal can be detected at signal-to-environmental noise ratios as low as 30 dB for the military and industrial noise sources investigated. Implementation of the method using a modified commercial HPD demonstrates a 7 dB improvement in warning alarm detection threshold compared with an unmodified HPD. Alternative methods for presenting the alarm signal to the user will be discussed as well as modifications to expand the method to accommodate multiple alarm signals.
Reduction of construction noise while building a recording studio
Authors: Beristain Sergio
Published: May 2014

While a new recording studio was being built within a large Audio and Video complex, construction noise had to be adequately controlled, in order to allow for the already existent audio recording studios and TV sets to continue with their normal activities along the building process. The noise was reduced by making a double wall system in the façade overlooking the construction area. Use was made of the already existing external wall, adjacent to the construction site, as the first wall of the system, and a second one was added in the exterior side of that wall in order to complete the double wall system, which contributed with a few dB's in the low frequency range, while getting a considerable noise level reduction in the high frequencies range to the overall noise reduction of the original wall. Producers and performers who were actually working in the existing studios were satisfied by the results obtained once the adaptation was complete. Details of the wall and its expected acoustical behavior are presented and discussed.
Use of the hammered dulcimer to demonstrate physical acoustics principles
Authors: Vongsawad Cameron T. , Gee Kent L. , Neilsen Tracianne B. , Christiansen Benjamin Y.
Published: May 2014

In 1636 AD, Marin Mersenne described the law of vibrating strings that relates frequency to length, tension, and density in L'Harmonie Universelle. One of the instruments described by Mersenne is the psalterion or hammered dulcimer. The dulcimer is a versatile struck-string instrument, based on the circle of fifths, in which the sound generation and radiation are linked to many physical acoustics principles. Some of these principles are basic: how string properties affect fundamental frequency; how the soundboard and body cavity give rise to different resonances; how hammer construction and excitation affect the spectrum; etc. Because of the ease of demonstrating acoustical principles with the hammered dulcimer, a 9/8 backpack-size dulcimer has been included as part of the new ASA outreach workshops held in conjunction with semiannual meetings. A description of these efforts and a short demonstration of the hammered dulcimer will be given. More advanced concepts to be discussed include high-speed video results of the hammer-string interaction as well as near-field acoustical holography analyses on a 16/15 Songbird® dulcimer. The holography shows how the sound holes, traditionally thought to be merely decorative, significantly influence the radiated sound.
Nonlinear experiments of tuning curve resonances for the vibrational modes of a weakly stretched circular membrane
Authors: Lloyd Benjamin W. , Korman Murray S.
Published: May 2014

Nonlinear oscillations of a pre-stretched 11.5 cm diameter latex circular membrane clamped rigidly around the boundary were investigated. The relaxed membrane thickness was 0.4 mm. An 8 cm diameter loud speaker drove the membrane from below using a swept sinusoidal tone. Low drive tuning curve sweeps demonstrated resonant frequencies corresponded to the first three radially symmetric linear drum modes (56, 147.6, and 240.5 Hz) sweeping from 50 to 300 Hz. Regression yielded a transverse wave speed of 10.6 m/s. Incrementally increasing the speaker amplitude (after each sweep) showed the lowest resonant frequency at first decreases, then increases with increasing acoustic drive pressure. Higher modes exhibited frequency increases with drive level. Tuning curve responses were measured using a 6 mm diameter microphone 5 mm above the center of the membrane. Nonlinear tuning curves hysteresis effects occur for higher drive levels sweeping between 50 and 70 Hz. Here, the amplitude sharply falls from a high to a low microphone response at fa = 59 Hz. With the same drive level, a sweep tone starting from 70 Hz to 50 Hz exhibits at fa = 57.5 Hz, a jump from a lower to a higher microphone response. [Goncalves et al., J. Vib. Sound 327, 231 (2009).]
Generation of photoacoustic transients from optically induced thermal gradients
Authors: Frez Clifford , Wu Binbin , Diebold Gerald
Published: May 2014

Irradiation of an absorbing surface in contact with a transparent fluid with a pulsed laser can result in the generation of extremely large thermal gradients. For example, when a laser with a pulse width of 10 ns and a fluence of 1 J/cm2 irradiates a region with an absorption of 1 cm1 having the thermal properties of liquid water, a thermal gradient on the order of 105 K/m at the interface is produced. Here, it is shown that the effect of such thermal gradients on photoacoustic waves from an infinite half space and from a uniformly irradiated sphere is the production of fast transients on the leading edges of the waves. The character of the transients is determined from an additional source term in the wave equation for pressure that obtains when heat conduction is taken into account. Experiments are reported showing the predicted transients on photoacoustic waves from absorbing layers in contact with transparent fluids irradiated with 10 ns laser pulses.
Comparison of experimental and theoretical mode studies on a square plate
Authors: Hansen Uwe J.
Published: May 2014

Standard two-dimensional Chladni patterns on a square plate are demonstrated and compared with the results of Finite Element mode calculations
The temporal acuity for processing interaural cues
Authors: van de Par Steven , Reed Darrin
Published: May 2014

It was during a three month visit of the first author to his Lab in 1998 that Tino pointed out an elegant study on detecting changes in Interaural Cross Correlation of stimuli that were roved in baseline Interaural Time Delay and Interaural Level Difference (Bernstein and Trahiotis, J. Acoust. Soc. Am. 102, 1113). This study showed that, even though ICC can only change due to the presence of dynamically varying ITDs and ILDs, the ICC can be perceived as a separate cue in certain conditions. This articulate notion of three perceptually independent binaural cues, ITD and ILD, relating to perceived laterality, and ICC, related to perceived width, is applied in low bit-rate audio coding where these cues are used to encode the spatial image of stereo sound recordings. The entanglement of these cues on a signal basis raises the question of the time scale at which these three cues are perceptually evaluated. Some recent findings will be discussed that show that the ITD and ICC can be evaluated with a high temporal acuity of less than 10 (ms) in stimuli where these cues alternate periodically, and that these patterns of alternating binaural cues give rise to a modulation percept.
Sound source localization: Clicks and click trains
Authors: Yost William , Zhong Xuan , Najam Anbar
Published: May 2014

Tino Trahiotis and Les Bernstein have provided valuable information about human listeners' ability to process interaural time differences in the envelopes of high-frequency carrier signals. These data have enriched models of binaural processing. In this paper, we explore sound source localization of click (100 microsecond transients) stimuli in the azimuth plane in the free field. We are especially interested in the sound source localization of click trains as they provide stimuli with robust envelope properties. We measured sound source localization accuracy for tones, single clicks, and click trains–unfiltered and filtered in low- and high-frequency regions. The filtering was performed to implicate the role of interaural time and level differences in sound source localization. These data involving clicks will be compared to recent findings from our laboratory involving sound source localization of broadband and filtered noise bursts as compared to sound source localization of umodulated and amplitude modulated tonal carriers. These data suggest that stimulus bandwidth is a major factor determining sound source localization accuracy, and that amplitude modulation plays a small role, at best, in determining sound source localization accuracy. The data involving click trains will help expand this database. [Research supported by the AFOSR.]
Combination of two consecutive monaural “looks” as a spatial hearing cue
Authors: Zhong Xuan , Yost William
Published: May 2014

Interaural time, level, and spectral differences are the major cues being used for sound source localization in the horizontal plane. Past studies have shown that human subjects could be trained to use monaural spectral cues to localize the sources of sound in the azimuth plane, but performance is poor. The current study investigates whether the combination of two monaural signals at both ears, one after another in time, could benefit sound source localization accuracy. The purpose is to study the possibility that the human subjects can compare a monaural signal at one ear to the short term memory of a prior monaural signal arriving at the other ear. Subjects were asked to judge the position of a loudspeaker that presented a 250-ms, 40 dBA noise burst with a roving spectral contour in a quarter field. The rms sound source localization error was measured in three conditions: (1) a single monaural signal; (2) two consecutive monaural “looks” at identical signals, with an interval of 3 s and (3) normal binaural hearing. It was found that the “two looks” localization performance was better than that in the case of monaural presentation, but is still inferior to that of the binaural presentation. Similar experiments were carried out over headphones. Lateralization performance was compared to the sound-field localization data. Contributions of level and spectral differences will be discussed. [Research supported by the AFOSR.]
Dynamics of geometrically reconfigurable one dimensional and two dimensional magneto-elastic metamaterials
Authors: Ruzzene Massimo , Schaeffer Marshall
Published: May 2014

Periodic structures are presented as metamaterials that exhibit multistability due to the nonlinearities of magneto-elastic interactions and structure geometry. The multistability of these structures affords them the ability to adapt their properties though geometric reconfiguration, bringing about changes in stiffness and Poisson's ratio, and introducing anisotropy. These changes in structural properties cause drastic changes in wave propagation, which is of interest for wave control. The dynamic transformation of one-dimensional (1D) and two-dimensional (2D) lattices between stable states are studied through nonlinear numerical simulations. The analysis is conducted using a lumped mass system of magnetic particles. The structures studied include hexagonal, re-entrant, and kagome lattices. Changes in plane wave propagation properties are predicted by applying Bloch theorem to lattice unit cells with linearized interactions. Results from Bloch analysis are then verified through direct numerical simulations. The propagation of plane waves in these lattices before and after topological changes is compared, and large differences are evident.
Control of the dynamic properties of nano cantilevers with structural imperfections
Authors: Rutner Marcus , Donskoy Dimitri , Conticchio Mark
Published: May 2014

Acoustic metamaterials can be made out of micro/nano size structures employing various structural elements such as cantilever oscillators [JASA, 132(4), 2866–2872]. Natural frequencies and eigenmodes depend on stiffness and mass distribution which should be reflected in macro as well as micro (nano) structure analysis. This study comprises three parallel approaches to model nano cantilever beams, i.e., the analytical method, the finite element analysis, and the molecular/atomic dynamics analysis, to identify how material imperfections influence the dynamic response of the nanocantilever. The study explores to what extent and under what circumstances macrostructure mechanics differs from nanostructure molecular/atomistic mechanics and how the built-in imperfection can be used to control structural dynamic properties at various scales.
Measuring visual contributions in phonetic categorization
Authors: Brancazio Lawrence
Published: May 2014

Although most of Joanne Miller's work has explored the mapping from the acoustic signal to phonetic categories, she has also investigated the contributions of visual phonetic information in this process (Green and Miller, 1985). Audiovisual integration is commonly assessed using the McGurk effect, an illusion occurring with audiovisually conflicting stimuli. We (Brancazio and Miller, 2005) suggested that the McGurk effect may underestimate visual contributions in speech perception, in part based on our finding that visual speaking rate influences phonetic judgments when the McGurk effect does not occur (with stimuli that typically produce the effect). Rather, audiovisual integration of incongruent stimuli might result in percepts that fall between phonetic categories—including the one consistent with the acoustic signal—and then are mapped onto one of these categories. Thus, variability in the incidence of the McGurk effect might reflect variability in the process of mapping onto phonetic categories more so than variability in audiovisual integration. In recent work, I have sought to disentangle some factors that might influence the magnitude of the McGurk effect. I will describe findings from recent studies involving variations on the standard McGurk paradigm, and discuss the implications for developing finer-grained methods of assessing audiovisual integration.
Neural sensitivity to phonetic category structure
Authors: Myers Emily
Published: May 2014

Much of the recent work on the neural bases of speech perception has concentrated on the phenomenon of categorical perception, and in particular the observation that listeners appear to ignore or be insensitive to acoustic variation within the phonetic category. This has led to a search for phoneme-level processes in the brain, while neglecting a crucial aspect of the speech category, namely, that phonetic categories contain rich internal structure. Pioneering research on phonetic category structure from Joanne L. Miller and her colleagues shows us that listeners are not only sensitive to variation within the phonetic category, but that this sensitivity is modulated by speech rate, context, and talker identity. Recent work from our group using fMRI shows that the neural systems underlying phonetic processing are likewise sensitive to phonetic category structure, with neural responses in the temporal lobes that reflect to the “goodness of fit” of a token to its phonetic category. In this paper I discuss evidence for the neural encoding of phonetic category structure, and in particular the sensitivity of this encoding to context and to experience.
Some neuromyths concerning the effectiveness of cochlear implants: Inferring function from dysfunction
Authors: Pisoni David B. , Pisoni David B.
Published: May 2014

Cochlear implants provide profoundly deaf infants and young children with access to critical temporal and spectral patterns of speech needed for language development. Despite the enormous benefits of cochlear implants, many controversial questions remain. I will consider ten pressing issues that are the focus of current efforts in the field: (1) individual variability in speech and language outcomes, (2) neuroplasticity and early implantation, (3) learning and linguistic experience, (4) linguistic vs indexical channels in speech perception, (5) bilateral vs. unilateral implantation, (6) Contribution of other neural and cognitive systems, (7) early predictors of outcomes and risk factors, (8) workload and mental effort, (9) speech in noise, and (10) acoustic simulations in normal-hearing listeners. These issues raise important theoretical questions about basic processes in speech perception and spoken language processing. Cochlear implant research may be viewed as a “model system” enabling inferences about normal function from the study of dysfunction providing additional converging support for the proposal that the ear does not function in isolation from the rest of the brain; it is an inseparable component of a complex adaptive self-organizing system that evolved to support the perception and production of spoken language. [Work supported by NIH Grants: R01 DC-XYZ and DC-ABC to Indiana University.]
Understanding the fine structure of speech: Contributions of Joanne L. Miller
Authors: Kuhl Patricia K.
Published: May 2014

As a graduate student in the 1960s, Joanne Miller was extremely well organized, exceptionally attentive to details, and very goal directed. When Joanne directed that level of attention toward the fine structure of speech and to theories explaining how human perceivers (both adult and infant) deciphered it, many important discoveries were made. In this talk, I'll review some of the data and theoretical arguments that Joanne Miller has put forward, and show how they advanced the field.
Imitation of a talker improves perception of the talker's speech
Authors: Dias James W. , Cook Theresa C. , Simmons Dominique C. , Dorsi Josh J. , Rosenblum Lawrence D.
Published: May 2014

Human perceivers have a tendency to imitate the idiolect (talker-specific articulatory style) of a perceived talker. This phonetic convergence manifests between perceivers during live conversations and when perceivers shadow (say aloud) the speech spoken by a pre-recorded talker. The following investigation explores the potential facilitative effects of phonetic convergence on subsequent perception of the imitated talker's speech. To test this, the strength of phonetic convergence was manipulated by varying the delay of perceivers' shadowing responses. When perceivers are required to delay their shadowing responses, phonetic convergence has been found to reduce [Goldinger, Psychol. Rev. 105(2), 215–279 (1998)]. If phonetic convergence can facilitate later perception of speech spoken by the shadowed talker, then perceivers who immediately shadow a talker should better identify the speech spoken by that talker, compared to perceivers who delayed their shadowing responses. Results suggest immediate—but not delayed—shadowing facilitates later identification of shadowed words spoken by the shadowed talker, compared to a non-shadowed talker. However, the facilitation effect does not transfer to utterances of novel (non-shadowed) words. The results may suggest a link between the mechanisms of speech perception and speech production based on idiolectic information available within lexical episodes.
Dances of the tongue: Temporal cues and temporal context in the production and perception of vowels
Authors: Strange Winifred
Published: May 2014

One focus of the research program of Joanne Miller and her colleagues has been on the influence of temporal context (including speaking rate) on the perception of consonant contrasts differentiated primarily by temporal cues (e.g., Voice Onset Time as a major cue for voicing contrasts; formant transition durations for manner contrasts). This talk will summarize some of my own findings on the role of temporal context (speaking style and rate) in the perception of vowels by native and non-native speakers of American English (AE). In AE Consonant-Vowel-Consonant syllables, duration varies systematically, but redundantly, among vowels contrasting in vowel “height,” cued primarily by first formant (F1) target frequency. Additional patterns of F1 temporal trajectories (timing of F1 maximum frequency and temporal symmetry/asymmetry of F1 onset and offset trajectories) differentiate so-called tense (long) and lax (short) AE vowels. Results of this research support the conception of speech production as a rhythmic activity with nested levels of timing control. Temporal patterns in syllabic- and multisyllabic-length segments of speech simultaneously provide information for phonetic identity and super-segmental structure within an exquisitely choreographed “dance” of the articulators. Differences in perception by native and non-native listeners support the conclusion that these are language-specific, learned patterns.
Talker contingency in spoken communication
Authors: Remez Robert E.
Published: May 2014

Those who speak the same language share its words, yet each spoken expression is unique, nonetheless. Research on the shared linguistic attributes perceived from highly varied physical acoustics has classically invoked the perturbations that drive expression from canonical phonemic form: coarticulation, articulatory rate variation, and anatomical scale variation. More recently, studies confirm that affect, dialect, idiolect, and idiosyncrasy also shape phonetic expression. Is the perception of this acoustic-phonetic variation prothetic, in which graded variation in physical acoustics creates similarly graded phonetic impressions? Some investigations of American English voicing encourage this view, though descriptive and perceptual studies also show that subphonemic phonetic expression can vary discontinuously in production and in perception. Overall, such studies of talker contingency in production and perception constrain claims of grammatical governance of articulation, and define new challenges of perceptual explanation.
Spatial coherence and radiated power for sound propagating in complex ocean environments
Authors: Duda Timothy
Published: May 2014

Underwater sound propagation in areas of complex bathymetry, variable water masses (fronts), or variable stratification can result in detailed patterns of signal phase and amplitude. Here, we examine a few of the countless scenarios with numerical simulation. Synthetic horizontal arrays can be laid down within the acoustic fields produced with time-varying three-dimensional acoustic simulations. The power received at the phones of the arrays and the spatial structures of amplitude and phase can be used to create an estimate of array-exploitable power transmitted from a source at a known location to positions throughout the environment. Maps of this parameter and its components (horizontal coherence length and incoherent power arriving at the arrays) are presented for multiple simulated environments, including offshore of Southern California and offshore of the eastern seaboard of the United States.
William M. Carey and the nonlinear frequency dependence of low frequency attenuation in sandy sediments
Authors: Pierce Allan D. , Siegmann William L. , Collis Jon M. , Evans Richard B. , Holmes Jason
Published: May 2014

The early “conventional wisdom” was that low frequency sediment attenuation could be predicted with a downward extrapolation with attenuation presumed directly proportional to frequency. This goes back to work at Woods Hole reported in a 1968 Bryn Mawr doctoral thesis by Bennett. However, the attenuation at such low frequencies is difficult to measure directly. In subsequent years, a number of investigators, including Carey and colleagues, using a variety of experimental techniques (all indirect) different from that of Bennett, found frequency dependences with exponents substantially larger than unity. A survey paper by Holmes, Carey, Dediu, and Siegmann in 2007 concluded that the appropriate exponent was approximately 1.8. Carey, however, felt that a substantial part of the community still clung to the belief that the dependence was linear, and led an effort to garner support from basic theory. Analytical models, including that of Biot and others based on a rigorous examination of water-sand-pebble interaction at low frequencies, predicted that the attenuation should be quadratic in frequency. Carey conjectured that the discrepancy was because the inference technique ignored the possibility of shear waves in the sediment. That this explained the discrepancy was subsequently confirmed with computations by Collis and theoretical analysis by Pierce.
Bill Carey and passive synthetic aperture
Authors: Sullivan Edmund
Published: May 2014

Although it was long a controversial subject in the acoustics community, passive synthetic aperture remained of great interest to Bill Carey. Over the years, there were several “proofs” that it couldn't be done in any practical way. These proofs were technically correct in terms of the models upon which they were based, but it eventually became clear that these models were quite constraining in that they had no relation to actual practice and further, were hamstrung in that they were centered on the concept of beamforming. It is shown how passive synthetic aperture was placed on a firm theoretical basis by avoiding the focus on a synthetic “beam pattern” and treating the bearing and range estimation as pure estimation problems, where the approach is based on a joint estimation of bearing and source frequency, or in the case of the wavefront curvature problem a joint estimation of bearing, source frequency and range. A history of Bill's contributions to the area is outlined and explanations of the shortcomings of the so-called “proofs” are discussed. Several examples of experimentally verified results are outlined and several examples are given.
Recollections on Chris Jaffe: From his early days in ASA through an enduring friendship of nearly six decades
Authors: Cavanaugh William J.
Published: May 2014

In some 60 years of consulting in architectural and environmental acoustics, one encounters few colleagues who fit the definition of a truly renaissance man. J. Christopher Jaffe is one of those few. His love for the performing arts and in designing facilities for the enjoyment of countless audiences and performers alike knew no bounds. My friendship with Chris began with hearing the very first paper he presented at an ASA meeting on the frequency selective properties of stage enclosures and extended throughout his entire professional career. Chris Jaffe epitomizes the challenge stated in the by-laws of our Society: to spread knowledge in acoustics and to promote its practical applications. Chris lived this challenge for a too short professional life with unabated enthusiasm and joy. We miss him terribly but are comforted that he made the world a better place.
Remembrances of Chris Jaffe—An innovator in many fields, our colleague, and friend
Authors: Bray Wade , Burkhard Mahlon D. , Genuit Klaus
Published: May 2014

A remembrance of Christopher Jaffe in the technical perspective will be given, in a matrix of the human perspective of working with him, learning from him and enjoying his vision, friendship, and wit. The authors all collaborated with Chris: Wade Bray as a consultant at Jaffe Acoustics, Mahlon Burkhard as an acoustical colleague and developer of electronic technologies proposed by Chris through the major era of the Electronic Reflected Energy System (ERES) starting with the “Live from Studio 8H” NBC television symphonic concerts—birth of the Chris-named “NBC Delay”—and Klaus Genuit fulfilling Chris's vision of binaural technology in multiple uses—Chris providing the avenue for HEAD acoustics GmbH to begin serving North America. Christopher Jaffe was a thorough, novel acoustician: fluent and innovative in both non-electronic and electronic techniques, though perhaps better known for his lifelong passion about the latter in the pure service of the listening experience and its reaching more people. He had a unique personal, charismatic presence, an ability not only to explain technical acoustics in artistic context to nontechnical people, but also to enfold them in the enthusiasm, skill and momentum of his spirit. We celebrate him; we miss him, his path lives.
The Jaffe effect
Authors: Glosemeyer Petrone Robin S.
Published: May 2014

By 1940, nearly every sizable city in America had a movie palace or movie-adapted vaudeville theater. As these regal houses for the silver screen were replaced by cinemas, the palaces and vaudeville theaters of the early 20th century sat with empty stages, taunting orchestras, theater companies, and would be audiences. Christopher Jaffe's most noted contribution to architectural acoustics was championing the adaptive re-use of these theaters through the development of an orchestra shell system. These light-weight shell systems allowed the theaters to support multiple performing arts organizations without a monumental capital campaign that neither the cities nor art organizations could afford. Chris' most singular contribution to acoustics was, however, his mentorship. This maverick in the field, always on a quest to prove himself, never missed an opportunity to share his knowledge or work out a new concept with a colleague or apprentice. He fostered the growth of consultants at all stages of their careers, first in his practice and later in the establishment of an architectural acoustics program at his alma mater.
Christopher Jaffe and the Graduate Program in Architectural Acoustics at Rensselaer Polytechnic Institute
Authors: Xiang Ning
Published: May 2014

Chris Jaffe graduated with a major in chemical engineering in 1949 from Rensselaer Polytechnic Institute. Four decades later in 1998, Chris founded an Architectural Acoustics program at the School of Architecture, Rensselaer Polytechnic Institute. In the fields of architectural-, physical-, and psycho-acoustics, the rapid pace of change has advanced the program to be a graduate program with an ambitious mission of educating future experts and leaders in architectural acoustics. Chris Jaffe's continued dedication and support helped Rensselaer's Graduate Program in Architectural Acoustics reshape its pedagogy using “STEM” (science, technology, engineering, and mathematics) methods, including intensive, integrative hands-on experimental components that fuse theory and practice in a collaborative environment. The STEM-based pedagogy enables individuals from a broad range of fields to succeed in this rapidly changing field. The program has attracted graduate students from a variety of disciplines including individuals with B.Arch., B.S., or B.A. degrees in Architecture, Music, Engineering, Audio/Recording Engineering, Physics, Mathematics, Computer Science, Acoustics, Electronic Media, and related fields. RPI's Graduate Program in Architectural Acoustics has since graduated more than 100 graduates with both M.S. and Ph.D. degrees. This paper shares the growth and evolution of the graduate program, and acknowledges the profound contributions made by Chris Jaffe.
Selection on aerial hearing in turtles: Auditory evoked potentials in the box turtle, Terrapene carolina relative to the stinkpot, Sternotherus odoratus
Authors: Zeyl Jeffrey , Johnston Carol E.
Published: May 2014

Mechanisms of auditory stimulation differ underwater versus in air due to differences in each medium's acoustic impedance, which has resulted in unique hearing adaptations in aquatic relative to terrestrial organisms. Testudines are a useful taxon for studying the evolution of hearing specializations in relation to the air-water interface because this group includes members at various points on the aquatic-terrestrial lifestyle continuum. Here we tested for differences in auditory function between the terrestrial box turtle, Terrapene carolina (Emydidae) and the fully aquatic stinkpot, Sternotherus odoratus (Kinosternidae). Auditory evoked potentials were collected in response to tone pips to generate threshold audiograms in air as well as with tympana submerged underwater. Sensitivities and bandwidths of both species were similar underwater and in air, but the thresholds of box turtles were 9–20 dB more sensitive than stinkpots in air across the entire frequency range. The results indicate selective pressures to enhance aerial hearing in box turtles.