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[AUDITORY] Fwd: Last call Conference on Sound Perception (CSP) on-line




Dear List,

The Organizing Committee of the Conference on Sound Perception (CSP) is very pleased to invite you to attend the

1st CSP Conference on 03 – 05 September 2021.

The conference is organized by the Department of Acoustics, at the Adam Mickiewicz University in Poznań.

Due to the Covid-19 pandemic, the CSP will be a virtual e-conference fully held in on-line mode.


Look through the Scientific Program and register here:

csp.amu.edu.pl


Our plenary lectures include, among others:

Avenues for improvement in hearing aids
Brian C.J. Moore, Department of Experimental Psychology, University of Cambridge, UK

Abstract: Despite the advances in signal processing in hearing aids over the past 20-30 years, hearing aids are still far from restoring “normal” hearing. This partly reflects limitations of impaired auditory systems, such as reduced frequency selectivity and reduced sensitivity to temporal fine structure, but also reflects limitations in the hearing aids themselves. Some very basic limitations are:
(1) The gains achieved on real ears are often substantially different from those programmed into the manufacturer’s software, even when averaged over many test ears. In other words, something is systematically wrong in the calibration of the fitting systems. A very common problem is a failure to meet target gains for frequencies above about 3 kHz.
(2) The compression ratios obtained on real ears are often substantially different from (usually below) those programmed into the manufacturer’s software. As a result, soft sounds remain inaudible and strong sounds are too loud.
(3) Despite claims of wide bandwidth, most hearing aids are unable to meet the fitting targets of methods like NAL-NL2 or CAM2 for frequencies above about 4 kHz.
(4) The output of many hearing aids often falls off markedly for frequencies below a few hundred Hz. This does not create severe problems when listening to speech, but produces severe degradations of sound quality for music.
More subtle problems arise as side effects of the signal processing in hearing aids. Processing such as multi-channel amplitude compression, noise reduction, and adaptive directionality changes the amplitude modulation patterns of the signal and this can have adverse effects on speech intelligibility and sound quality. For listening to music, many hearing-impaired people prefer a linear amplifier with high-quality headphones to their hearing aids. There is increasing evidence that the intelligibility of speech in background sounds is strongly affected by the amplitude fluctuations in the background sounds, even for “steady” noise. Improved models for predicting the intelligibility of speech in fluctuating background sounds are needed to assess the deleterious effects of the processing in hearing aids, and to select parameters of the processing that minimise these deleterious effects.
Much work is being conducted to develop “cognitively controlled” hearing aids, that selectively enhance the voice of the talker who the listener wishes to hear. The prospects for such devices will be discussed.

The role of envelope cues in masking
 Armin Kohlrausch, Chair of Auditory and Multisensory perception at Eindhoven University of Technology, The Netherlands

Abstract: In this presentation I will give an overview on how the thinking about envelope cues has evolved in the past decades. I will focus the presentation on masking conditions with a random noise masker and a tonal signal. Historically, those conditions have been analyzed in terms of the change in energy introduced by the addition of the signal. Data analysis based on such an energy detection lead to the concepts of critical bands and critical ratios, where signal thresholds were measured in bandpass noises of varying bandwidths. Thresholds of signals being placed in a spectral notch of a bandstop noise led to the auditory filter concept and the ERB scale. Energy detection models were challenged in the 1980’s by a range of paradigms. Random variations (level rove) of the noise level from interval to interval render the energy cue much less effective, but human thresholds remain nearly unaffected, suggesting the use of additional cues. This observation has motivated the use of envelope-based cues, including the mean envelope slope value (Richards, 1992), in tone-in-noise detection. Secondly, in profile analysis with narrowband stimuli, the profile changes in the modulation spectrum derived from the stimulus envelope were proposed as a cue (Green et al., 1992). And finally, in masking experiments with harmonic complex tone maskers, the waveform changes enabled by choosing different phase values for the individual components emphasized the role of changes in the envelope structure instead of changes in the overall energy. In this talk, I will present a unified framework, in which results from these different paradigms can be understood by a detection process making use of the same detection cues.

See You there fully on-line,

Organizing Committee