In wave field synthesis, however, we synthesize all these components during playback. In this way the geometry of the room is optimally matched, yielding better coverage of the audience and reduction of spatial. This approach, based on wave field synthesis berkhout 1988 and berkhout et al. It presents this system, which is called virtual wave field synthesis, and. Engineering in 1988 and the phd in 1995 from the university of erlangen, germany. We present our experiences of combining wave field synthesis audio with a projectionbased multiviewer stereo display. Papers multiactuator panels for wave field synthesis. It allows the synthesis of wave fronts that appear to emanate from a virtual source at a defined position. A fundamental limitation of wfs is that the synthesis remains correct only up to a corner frequency referred to as spatial aliasing frequency. The method can also be applied to impulse responses measured in an existing hall. Create an open source, crossplatform wave field synthesis software environment 3.
Enhance wave field synthesis by practically extending the virtual source space to the vertical dimension. The proposed formulation relies on an ensemble of elementary directivity functions based on a subset of spherical harmonics. Wave field synthesis is able to simulate spatial sound sources of various kinds without the need for headphones or user tracking. Even so, the most important advantage of wave field synthesis is hardly mentioned in all the scientific publications. This paper proposes a simulation system capable to simulate wave field synthesis systems in different rooms based on physical measurements of loudspeakers in each room. Spatial aliasing artifacts produced by linear loudspeaker. Wave field synthesis driving functions for largescalesound reinforcement using line source arrays frank schultz 1, gergelyfirtha2, peterfiala 2, sascha spors 3 1audio communication group, tu berlin. Jens ahrens, sound field synthesis for rudolf rabenstein. Wave field synthesis is arguably the most impressive surround sound system currently available. The superposition of all the secondary sources form a waveform which is physically indistinguishable from the shape of the original wave front 21. Removes the restriction to the horizontal plane without using a complete plane array. Analysis of near field effects of wave field synthesis using linear loudspeaker arrays sascha spors and jens ahrens 1deutsche telekom laboratories, ernstreuterplatz 7, 10587 berlin, germany. Wave field synthesis driving functions for largescalesound.
Wave field synthesis in three dimensions by multiple line arrays. The module is built so that the speakers are as close to point sources as possible. Tool support monostereo, 8 bit16 bit wav files with a range of sampling rates. Acoustic control by wave field synthesis 2769 the position of a microphone is very flexible, as long as it is directed to its assigned source area and the. Wave field synthesis wfs is a technique allowing the reproduction of sound fields in an extended listening area. It produces artificial wavefronts synthesized by a large number of individually driven loudspeakers. Sound sources can come from sampling or artificial synthesis. Wave field synthesis wfs is a computationally expensive but very powerful and advanced way of creating highly immersive audio environments. It relies on linear arrays of regularly spaced omnidirectional loudspeakers.
Highquality acoustic rendering with wave field synthesis s. Contrary to traditional spatialization techniques such as stereo. Spatial sound reproduction with wave field synthesis. The secondary sources therefore act as a relay, and can reproduce the original primary wave front in absence of a primary source. Practical implementations of physicsbased spatial sound reproduction techniques, such as wave field synthesis wfs and higher order ambisonics hoa, require realtime filtering, scaling and delaying operations on the audio signal to be spatialized. Mar 07, 2011 the worlds only transportable wave field synthesis system, from the game of life gameoflife. Boone laboratory of acoustical imaging and sound control delft university of technology p. Aes elibrary equalization of wave field synthesis systems. Recently a local wave field synthesis technique has been published which. The underlying theory, however, assumes a continuous distribution of loudspeakers. With wave field synthesis you are not limited to placing sources in depth and width, but you can also work with height. This page focuses on those methods that provide analytical solutions to the underlying mathematical problem, namely wfs wave field synthesis, nfchoa near field compensated.
Auralization of sound fields by wave field synthesis. A plane wave field was chosen only for the sake of simplicity. Individual loudspeakers placed at discrete positions constitute a spatial sampling process. This method for 3d sound synthesis creates a sound world by attaching a characteristic sound to each object in the scene. Introduction wave field synthesis wfs is a physicsbased sound reproduction technique 1, 2. In the past, the spatial aliasing artifacts of wfs have mainly been investigated for the reproduction of monochromatic signals, and hence in the frequency domain. On fractional delay interpolation for local wave field. Wave field synthesis wfs is a spatial sound reproduction technique that uses a high number of densely placed loudspeakers secondary sources. Aes elibrary analysis of nearfield effects of wave field.
Evolution and present developments basilio pueo1, aes member, jose. Wave field synthesis is a reproduction technique using a large number of densely placed loudspeakers loudspeaker array. Pdf spatial sampling artifacts of wave field synthesis. It is discussed that the reproduction of stereophonic recordings is possible using wfs. Holoplot audio technology based on wave field synthesis. This synthesized wave front will be perfectly accurate outside of the zone delimited by the secondary source distribution.
Dec 08, 20 ive just been sent this great new photo from our research labs. Updates of the wonder software interface for using wave field. On fractional delay interpolation for local wave field synthesis fiete winter and sascha spors abstract wave field synthesis aims at the accurate reproduction of a sound. Wave field synthesis in audio applications can be implemented in a straightforward way by driving a line array of loudspeakers.
Wave field synthesis, fractional order systems, loudseaker array, soundscapes. The basic theory behind it is not very complex, but the technological effort is immense. Pdf spatial sound reproduction with wave field synthesis. Wave field synthesis, spatialisation 1 introduction wave field synthesis wfs is a technique for sound spatialisation, that overcomes the main shortcoming of other spatialisation techniques, as there is a large listening area and no sweet spot. This principle is applied in acoustics by using a large number of small and closely spaced.
Each point on a wave front can be regarded as the origin of a point source. Wfs aims at recreating the sound field of acoustic sources using an ensemble of loudspeakers positioned at the boundaries of the listening. Wave field synthesis with realtime control william francis wolcott iv wave. The wfs formulation introduces artifacts in the synthesized sound field for both. Contrary to traditional spatialization techniques such as stereo or. Spatial sound reproduction systems with a large number of loudspeakers are increasingly being used. Ball of sound speherical loudspeaker arrays could help create a more realistic audio experience in theatres and concert halls. Pdf highquality acoustic rendering with wave field. Multiactuator panels are used as alternatives to arrays of classic loudspeakers with conically shaped diaphragms for wave field synthesis, with added benefits such as low visual profile and. Thus it remains impossible for the handling of each of these components in a different manner during playback.
On the use of irregularly spaced loudspeaker arrays for. Well discuss in this article the possible consequences on a pa with speakers on the floor usually for the front rows in the audience and a flown system for the audience sitting further from the stage. Physical properties of local wave field synthesis using. Wavetable synthesis, also known as samplebased synthesis, refers to a type of synthesis where the sound constructed is modelled on the single cycle waveform of a sound source. The report is addressed to anyone with an interest in wave field synthesis, but is primarily intended to students and supervisors of the esector at aalborg university. Analysis of nearfield effects of wave field synthesis using.
Gnss overtheair testing using wave field synthesis alexander rugamer. Basics and applications karlheinz brandenburg, sandra brix, thomas sporer. The results show that the enhanced reproduction accuracy in local wave field synthesis leads to a reduction of perceived colouration, if a suitable parametrisation is chosen. Introduction wfs audio system setup prototypes conclusion future combining wave field synthesis audio and multiviewer stereo displays janp. A discretization of the wave field synthesis method for. Wavefield synthesis for maxmsp aalborg universitet. Jun 06, 2018 furthermore, the influence of different parametrisations for local wave field synthesis is investigated. Wave field synthesis wfs is a digital signal processing technique introduced to achieve an optimal acoustic sensation in a larger area than in traditional systems stereophony, dolby digital. References to literature are in squared brackets with the number that appears in the bibliography, e. Wave field synthesis wfs is a physical based sound reproduction technique. Conventional and distributed mode loudspeaker arrays for the application of wave field synthesis to videoconference jose j.
In this project a wave field synthesis wfs system using a linear array of loudspeakers is implemented. Highquality acoustic rendering with wave field synthesis. Taking advantage of the huygens principle, wave fronts are simulated with a large array of speakers. Basics and applications karlheinz brandenburg, sandra brix, thomas sporer technische universitat ilmenau fraunhofer institute for digital media technology idmt llmenau, germany. This paper focuses on the control and application of a curved loudspeaker array of any desired shape and consisting of several linear arrays. It isnt something youre likely to see outside a research laboratory, however, because of the large amount of equipment that is required. The theoretical driving function for the loudspeakers states, that a correction filter must be implemented to get a flat frequency response of the system.
Lopez, basilio pueo and maximo cobos institute for telecommunications and multimedia applications iteam technical university of valencia, spain abstract this paper presents two prototypes for the application. Focusses sound in sonic space wave field synthesis is the first sound reproduction technique that enables sound to be truly that is physical instead of psycho acoustic distributed spatially. These can be combined to create and manipulate directivity characteristics of the synthesized virtual sources. Wave field synthesis allows the reproduction of arbitrary wave fields in a large listening area. He showed that sound control could be based on acoustic holography, which is also called wave eld extrapolation. A brief history the cornerstone of modern sound field synthesis theory was laid by jessel 1973, whose work is based on some of the most fundamental integral equations in the physics of wave fields such as the rayleigh integrals or the kirchhoff. That sound source can be a note of a natural sound, like a voice, drum kick, etc. Using wave field synthesis, holoplot systems create genuine sound fields that reshape the acoustics of the venue and address all three elements. This method, when implemented with all its potentials, enables the perceptual assessment of the complete hall design without the use of headphones, i. Combining wave field synthesis and multiviewer stereo. The synthesis of directional sources using wave field synthesis is described. Pdf investigation of spatial aliasing artifacts of wave. Physical properties of local wave field synthesis using circular loudspeaker arrays fiete winter and sascha spors institute of communications engineering. Next, the theoretic fundamentals of wave field synthesis are detailed.
Authentic sound reproduction requires the independent configuration of all these three elements. Wave field synthesis enables acoustic control in a listening area by systematic regulation of loudspeaker signals on its boundary. Wave field synthesis wfs is a sound field rendering technique that allows for spatial sound reproduction over a large listening area 123. Utility never lost constrains whenever you join, add or combine multiple wav files into one. Apex wave merger apex pdf splitter merger, pdf password. In this paper, we compare the architectural perspectives of the wave field synthesis wfs 3daudio algorithm mapped on three different platforms. Wave field synthesis wfs has been developed almost 20 years ago the theory is well documented for linear loudspeaker arrays some extensions towards twothree dimensional arbitrarily shaped wfs systems. Apex wav merger software is basically designed for merging two or more. A plane wave with propagation direction 90 was defined as the desired sound field to be synthesized in the bright zone in the case of the pressure matching and the hybrid method.
True sound is the product of direct sound, reflections and time. Wave field synthesis wfs is a spatial audio rendering technique, characterized by creation of virtual acoustic environments. Wave field synthesis wfs has been developed almost 20 years ago the theory is well documented for linear loudspeaker arrays some extensions towards twothree dimensional arbitrarily shaped wfs. All points on a wave front serve as individual point sources of spherical secondary wave fronts.
In conventional audio all signal components, as the direct wave, first reflections and the reverberation, merge together inseparably in a common signal. A huge array of independently controlled speakers is used to create the same pressure wave as a virtual source. Twoway acoustic window using wave field synthesis masters thesis submitted in partial ful. The size of the stereo sweet spot can even be increased.
Sources are steered with wave field synthesis in the horizontal direction, and with amplitude panning in the. The theory of wave field synthesis revisited sascha spors, rudolf rabenstein, and jens ahrens 124th convention of the audio engineering society amsterdam, 2008 may 1720. Spors et al theory of wfs revisited page 1 motivation wave field synthesis wfs has been developed almost 20 years ago. Synthesis of directional sources using wave field synthesis. Since 2001 he is head of a department at the fraunhofer iis dealing with the develop. This implies a spatial sampling process that may lead to aliasing artifacts. Sound rendering as a method for 3d sound synthesis sound rendering is a technique of generating a synchronized soundtrack for animations. Wavefieldsynthesis wfs is based on the wave theory concept of huygens. On the use of small microphone arrays for wave field.
On the use of small microphone arrays for wave field synthesis auralization maximo cobos1, sascha spors2, jens ahrens2 and jose j. Combining wave field synthesis audio and multiviewer. The wave field synthesis wfs concept, according to which sound waves are generated using arrays of loudspeakers, enables the realization of sound fields with natural properties in time and space, not on a few sweet spots, but in an entire audience area, for a variety of applications. This chapter starts with an overview including the history of wave field synthesis and some exemplary installations. Wave field synthesis in three dimensions by multiple line. Such wavefronts seem to originate from a virtual starting point, the virtual source or notional source. Wave field synthesis for 3d audio proceedings of the 6th.
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