Guitars with Ambisonic Spatial Performance (GASP): An immersive guitar system

The GASP project investigates the design and realisation of an Immersive Guitar System. It brings together a range of sound processing and spatialising technologies and applies them to a specific musical instrument ‒ the Electric Guitar. GASP is an ongoing innovative audio project, fusing the musical with the technical, combining the processing of each stringʼs output (which we called timbralisation) with spatial sound. It is also an artistic musical project, where space becomes a performance parameter, providing new experimental immersive sound production techniques for the guitarist and music producer. Several ways of reimagining the electric guitar as an immersive sounding instrument have been considered, the primary method using Ambisonics. However, additionally, some complementary performance and production techniques have emerged from the use of divided pickups, supporting both immersive live performance and studio post-production. GASP Live offers performers and audiences new real-time sonic-spatial perspectives, where the guitarist or a Live GASP producer can have real-time control of timbral, spatial, and other performance features, such as: timbral crossfading, switching of split-timbres across strings, spatial movement where Spatial Patterns may be selected and modulated, control of Spatial Tempo, and real-time performance re-tuning. For GASP recording and post-production, individual string note patterns may be visualised in Reaper DAW,2 from which, analyses and judgements can be made to inform post-production decisions for timbralisation and spatialisation. An appreciation of auditory grouping and perceptual streaming (Bregman, 1994) has informed GASP production ideas. For performance monitoring or recorded playback, the immersive audio would typically be heard over a circular array of loudspeakers, or over headphones with head-tracked binaural reproduction. This paper discusses the design of the system and its elements, investigates other applications of divided pickups, namely GASPʼs Guitarpeggiator, and reflects on productions made so far

Guitars with Ambisonic Spatial Performance (GASP) An immersive guitar system

The GASP project investigates the design and realisation of an Immersive Guitar System. It brings together a range of sound processing and spatialising technologies and applies them to a specific musical instrument – the Electric Guitar. GASP is an ongoing innovative audio project, fusing the musical with the technical, combining the processing of each string’s output (which we called timbralisation) with spatial sound. It is also an artistic musical project, where space becomes a performance parameter, providing new experimental immersive sound production techniques for the guitarist and music producer. Several ways of reimagining the electric guitar as an immersive sounding instrument have been considered, the primary method using Ambisonics. However, additionally, some complementary performance and production techniques have emerged from the use of divided pickups, supporting both immersive live performance and studio post-production. GASP Live offers performers and audiences new real-time sonic-spatial perspectives, where the guitarist or a Live GASP producer can have real-time control of timbral, spatial, and other performance features, such as: timbral crossfading, switching of split-timbres across strings, spatial movement where Spatial Patterns may be selected and modulated, control of Spatial Tempo, and real-time performance re-tuning. For GASP recording and post-production, individual string note patterns may be visualised in Reaper DAW,2 from which, analyses and judgements can be made to inform post-production decisions for timbralisation and spatialisation. An appreciation of auditory grouping and perceptual streaming (Bregman, 1994) has informed GASP production ideas. For performance monitoring or recorded playback, the immersive audio would typically be heard over a circular array of loudspeakers, or over headphones with head-tracked binaural reproduction. This paper discusses the design of the system and its elements, investigates other applications of divided pickups, namely GASP’s Guitarpeggiator, and reflects on productions made so far

The HOA library, review and prospects

International audienceIn this paper, we present the HOA Library, an open source high order ambisonic spatialisation tools collection programmed in C++. We expose the objectives and characteristics of the project, which treat the potential of high order Ambisonics in a musical perspective, based on the practice and the creativity of the electronic musicians. We clarify the context of use, the choice of optimization and decoding. We review the implementations of thelibrary in various environments, such Max, Pure Data, and Faust. We discuss the use of feedback from musicians and members of especially Max and Pure Data community. Finally, we advance the prospects of the HOA library in its current developments in three dimensions

Multi-point nonlinear spatial distribution of effects across the soundfield

This paper outlines a method of applying non-linear processing and effects to multi-point spatial distributions of sound spectra. The technique is based on previous research by the author on non-linear spatial distributions of spectra, that is, timbre spatialisation in the frequency domain. One of the primary applications here is the further elaboration of timbre spatialisation in the frequency domain to account for distance cues incorporating loudness attenuation, reverb, and filtration. Further to this, the same approach may also give rise to more non-linear distributions of processing and effects across multi-point spatial distributions such as audio distortions and harmonic exciters, delays, and other such parallel processes used within a spatial context

Spectromorphology and spatiomorphology of sound shapes: Audio-rate AEP and DBAP panning of spectra

Explorations of a new mapping strategy for spectral spatial-isation demonstrate a concise and flexible control of both spatiomorphology and spectromorphology. With the crea-tion of customized software by the author for audio-rate histograms, spectral processing function smoothing, spec-tral centroid width modulation, audio-rate distance-based amplitude panning, audio-rate ambisonic equivalent pan-ning, a growing library of audio trajectory functions, and an assortment of spectral transformation functions, this article tries to explain the rationale of this process

Tissue-conducted spatial sound fields

We describe experiments using multiple cranial transducers to achieve auditory spatial perceptual impressions via bone (BC) and tissue conduction (TC), bypassing the peripheral hearing apparatus. This could be useful in cases of peripheral hearing damage or where ear-occlusion is undesirable. Previous work (e.g. Stanley and Walker 2006, MacDonald and Letowski 2006)1,2 indicated robust lateralization is feasible via tissue conduction. We have utilized discrete signals, stereo and first order ambisonics to investigate control of externalization, range, direction in azimuth and elevation, movement and spaciousness. Early results indicate robust and coherent effects. Current technological implementations are presented and potential development paths discussed

A distributed approach to surround sound production

The requirement for multi-channel surround sound in audio production applications is growing rapidly. Audio processing in these applications can be costly, particularly in multi-channel systems. A distributed approach is proposed for the development of a realtime spatialization system for surround sound music production, using Ambisonic surround sound methods. The latency in the system is analyzed, with a focus on the audio processing and network delays, in order to ascertain the feasibility of an enhanced, distributed real-time spatialization system

A Comparison of Audio Models for Virtual Reality Video

This paper investigates the relationship between audio models for Virtual Reality (VR) video with respect to the senses of immersion and realism that each model delivers. Mono, Stereo, 5.1 Surround Sound, and a Virtual Spatialised Position configuration was developed for testing in a VR music video and evaluated with a user study. Participants experienced the VR video with these differing audio models as accompaniment a total of four times. Qualitative and quantitative data were recorded to evaluate user experience. The results indicate that no statistical significance was present between the four models in relation to immersion or realism, suggesting that complex audio renderings are not always necessary for effective user experience