Timbre, Sound Quality, and Sound Design

International audienceSound quality evaluation applies the results of timbre research to the assessment of the sound quality of manufactured products (domestic appliances, transportation, etc.). This chapter first provides an overview of one methodology. A number of acoustic descriptors reflecting perceived timbre dimensions are established and used to predict users' preference judgements. Whereas such a methodology has proven very effective, it also has some limitations. In fact, most studies only consider the pleasantness of the sounds and often overlook other potential roles of sounds in products and interfaces. In the second part, the chapter introduces sound design. Whereas sound quality evaluation merely proposes a diagnostic of the timbre of existing products, sound design aims to create or modify the timbre of product sounds to meet specific intentions. These intentions consider the pleasantness, but also several other aspects of product sounds: functionality, identity, and ecology. All these aspects are interdependent and often closely related to the temporal and timbral characteristics of the sound. The chapter continues with a discussion of the roles and practices of sound designers and introduces a set of tools that foster communication about timbre between the different participants of a sound design process. In particular, the focus is on the necessity for these participants to share a common timbre vocabulary, and the potential impact of education about sounds is considered. Finally, an important functional aspect of product sound is discussed: how to design the timbre of sounds to support user interactions with the product

Is loudness part of a sound recognition process?

International audienceInfluence of loudness on sound recognition was investigated in an explicit memory experiment based on a conscious recollection-test phase-of previously encoded information-study phase. Three encoding conditions were compared: semantic (sounds were sorted in three different categories), sensory (sounds were rated in loudness), and control (participants were solely asked to listen to the sounds). Results revealed a significant study-to-test change effect: loudness change between the study and the test phases affects recognition. The effect was not specific to the encoding condition (semantic vs sensory) suggesting that loudness is an important hint for everyday sounds recognition. [Q-JF] Dat

Sketching sound with voice and gesture

Insights: In product and interaction design, sounds should be included in the early stages of the design process. Voice and gestures are natural sketching tools that we can exploit to communicate sonic interactions

Backscattering suppression in supersonic 1D polariton condensates

We investigate the effects of disorder on the propagation of one-dimensional polariton condensates in semiconductor microcavities. We observe a strong suppression of the backscattering produced by the imperfections of the structure when increasing the condensate density. This suppression occurs in the supersonic regime and is simultaneous to the onset of parametric instabilities which enable the "hopping" of the condensate through the disorder. Our results evidence a new mechanism for the frictionless flow of polaritons at high speeds.Comment: 5 pages, 3 figure

The Egocentric Nature of Action-Sound Associations

Actions that produce sounds infuse our daily lives. Some of these sounds are a natural consequence of physical interactions (such as a clang resulting from dropping a pan), but others are artificially designed (such as a beep resulting from a keypress). Although the relationship between actions and sounds has previously been examined, the frame of reference of these associations is still unknown, despite it being a fundamental property of a psychological representation. For example, when an association is created between a keypress and a tone, it is unclear whether the frame of reference is egocentric (gesture-sound association) or exocentric (key-sound association). This question is especially important for artificially created associations, which occur in technology that pairs sounds with actions, such as gestural interfaces, virtual or augmented reality, and simple buttons that produce tones. The frame of reference could directly influence the learnability, the ease of use, the extent of immersion, and many other factors of the interaction. To explore whether action-sound associations are egocentric or exocentric, an experiment was implemented using a computer keyboard’s number pad wherein moving a finger from one key to another produced a sound, thus creating an action-sound association. Half of the participants received egocentric instructions to move their finger with a particular gesture. The other half of the participants received exocentric instructions to move their finger to a particular number on the keypad. All participants were performing the same actions, and only the framing of the action varied between conditions by altering task instructions. Participants in the egocentric condition learned the gesture-sound association, as revealed by a priming paradigm. However, the exocentric condition showed no priming effects. This finding suggests that action-sound associations are egocentric in nature. A second part of the same session further confirmed the egocentric nature of these associations by showing no change in the priming effect after moving to a different starting location. Our findings are consistent with an egocentric representation of action-sound associations, which could have implications for applications that utilize these associations

Prioritizing signals for selective real-time audio processing

Presented at the 11th International Conference on Auditory Display (ICAD2005)This paper studies various priority metrics that can be used to progressively select sub-parts of a number of audio signals for realtime processing. In particular, five level-related metrics were examined: RMS level, A-weighted level, Zwicker and Moore loudness models and a masking threshold-based model. We conducted a pilot subjective evaluation study aimed at evaluating which metric would perform best at reconstructing mixtures of various types (speech, ambient and music) using only a budget amount of original audio data. Our results suggest that A-weighting performs the worst while results obtained with loudness metrics appear to depend on the type of signals. RMS level offers a good compromise for all cases. Our results also show that significant sub-parts of the original audio data can be omitted in most cases, without noticeable degradation in the generated mixtures, which validates the usability of our selective processing approach for real-time applications. In this context, we successfully implemented a prototype 3D audio rendering pipeline using our selective approach

Real-time detection of overlapping sound events with non-negative matrix factorization

International audienceIn this paper, we investigate the problem of real-time detection of overlapping sound events by employing non-negative matrix factorization techniques. We consider a setup where audio streams arrive in real-time to the system and are decomposed onto a dictionary of event templates learned off-line prior to the decomposition. An important drawback of existing approaches in this context is the lack of controls on the decomposition. We propose and compare two provably convergent algorithms that address this issue, by controlling respectively the sparsity of the decomposition and the trade-off of the decomposition between the different frequency components. Sparsity regularization is considered in the framework of convex quadratic programming, while frequency compromise is introduced by employing the beta-divergence as a cost function. The two algorithms are evaluated on the multi-source detection tasks of polyphonic music transcription, drum transcription and environmental sound recognition. The obtained results show how the proposed approaches can improve detection in such applications, while maintaining low computational costs that are suitable for real-time

Synthesis of novel heteroleptic delocalised cationic pyrazole gold complexes as potent HepG2 cytotoxic agents

A new series of cationic gold(I) pyrazole complexes were prepared in excellent yields as their perchlorate salts. Results of cell viability assays show that these novel complexes have good cytotoxic properties against the human HepG2 cancer cell line. These complexes showed promising anti-cancer activities and to our knowledge, pyrazoles have never been tested against this cell line. The regioselectivity of the complexation is also discussed in regards to the substitution pattern of the pyrazoles

Reference-free compression of high throughput sequencing data with a probabilistic de Bruijn graph

International audienceData volumes generated by next-generation sequencing (NGS) technologies is now a major concern for both data storage and transmission. This triggered the need for more efficient methods than general purpose compression tools, such as the widely used gzip method.We present a novel reference-free method meant to compress data issued from high throughput sequencing technologies. Our approach, implemented in the software LEON, employs techniques derived from existing assembly principles. The method is based on a reference probabilistic de Bruijn Graph, built de novo from the set of reads and stored in a Bloom filter. Each read is encoded as a path in this graph, by memorizing an anchoring kmer and a list of bifurcations. The same probabilistic de Bruijn Graph is used to perform a lossy transformation of the quality scores, which allows to obtain higher compression rates without losing pertinent information for downstream analyses.LEON was run on various real sequencing datasets (whole genome, exome, RNA-seq or metagenomics). In all cases, LEON showed higher overall compression ratios than state-of-the-art compression software. On a C. elegans whole genome sequencing dataset, LEON divided the original file size by more than 20. LEON is an open source software, distributed under GNU affero GPL License, available for download at http://gatb.inria.fr/software/leon/