1	THREE-DIMENSIONAL ACOUSTIC DISPLAYS IN A MUSEUM EMPLOYING WFS (WAVE FIELD SYNTHESIS) AND HOA (HIGH ORDER AMBISONICS) Angelo Farina^1,2, Andrea Capra^1,2, Paolo Martignon^1,4, Simone Fontana^1,2,3, Fons Adriaensen¹, Paolo Galaverna¹ and Dave Malham⁵ 1 LAE - Laboratory for Acoustics and Electroacoustics, Parma, ITALY, HTTP://www.laegroup.org 2 University of Parma, Industrial Engineering Dept., Parma, ITALY 3 Ecole Nationale Superieure de Telecommunications (ENST), Paris, FRANCE 4 University of Ferrara, LAV (Laboratory for Acoustics and Vibrations) Ferrara, ITALY 5 Music Research Centre, Department of Music, The University of York, UK
2	The “Casa del Suono” It was born thanks to the cooperation of University of Parma, Comune of Parma, and with funds (approximately 2 million Euros) provided by Casa della Musica, Italian Governement and Cariparma Foundation The institutional goal is to display the famous Patanè’s Collection of vintage grammophones and radios, made available by CNIT (National Italian Consortium for Telecommunications) It is also a research lab about electroacoustics, equipped with the latest technologies for sound recording and reproduction employing a large number of channels
3	Topics Restoration of the S.Elisabetta church Exhibit of Patanè’s Collection Sound system for the exhibit The SONIC CHANDELLIER, an innovative planar WFS installation 30-seats listening room (linear WFS) The single-seat listening room (Binaural, Ambisonics, Ambiophonics)
4	The S.Elisabetta Church
5	The S.Elisabetta Church
6	The S.Elisabetta church
7	The S.Elisabetta church
8	The S.Elisabetta church
9	The exhibit
10	The exhibit
11	Patanè’s Collection The collection was donated to CNIT by don Giuseppe Patanè, a priest and a collector, who employed his entire, long life for searching, purchasing and repairing valuable pieces. The collections contains approximately 400 pieces, ranging from the first phonographs, to Galen radios and extends to domestic and military radios of 20’s, 30’s, 40’s up to the first years after WWII. All pieces have been carefully maintained and serviced, most of them are working as new.... There are also some particularly rare pieces, such as a cryptographic “Enigma” machine, employed by the German army for transmitting encoded informations during WWII.
12	Patanè’s Collection Some samples from the collection
13	Patanè’s Collection Some samples from the collection
14	Patanè’s Collection Some samples from the collection
15	Exhibit’s sound system
16	Exhibit’s sound system
17	DSP control of line arrays
18	DSP control of line arrays
19	The Niches
20	The Niches
21	The Niches
22	The Niches
23	The Niches
24	The Niches
25	The “Sonic Chandellier”
26	Design and Construction
27	Design and Construction
28	Installation
29	Hardware (computer, converters, amplifiers)
30	Hardware (computer, converters, amplifiers)
31	Software
32	Software
33	Listening rooms
34	Listening rooms La sala bianca ospita sino a 30 ascoltatori, ed è dotata di un sistema surround planare tipo WFS (192 altoparlanti)
35	30-seats room (“sala Bianca”) 176 loudspeakers are incorporated in the perimetral walls, completely surrounding the audience at ear-height
36	The WFS technology Wave Field Synthesis is a playback technique which makes use of linear loudspeaker arrays which are used for creating wavefronts appearing to be radiated by a virtual source Concept: spatially sampling a wavefront
37	WFS applications WFS can generate point sources or planar sources, and even point sources which appear to be inside the room, in the middle of the audience area
38	Tecnology WFS @ IRCAM, IRT
39	Synthesis of a virtual environment with WFS
40	FREE Software for WFS The Linux program Wonder makes it possibile to generate WFS signals and to move in realtime the virtual source being synthesized
41	Low-cost hardware for WFS The cheaper solution is based on a PC containing three MADI interfaces (64 ch. each), connected with a rack of low-cost converters (Behringer)
42	Single-seat room (“sala Nera”) This room is equipped with 26 loudspeakers
43	Single-seat room The walls are made by plywood, gypsum boards and perforated panels with polyesther fiber wool, providing good sound insulation and optimal control of reverberation
44	Single-seat room The sound absorbing treatment, here simulated employing the Ramsete program, provides a value of T20 of 0.40 s at 125 Hz and even lower ar higher frequencies.
45	Binaural (Stereo Dipole) method Playback is made on 2 loudspeakers located at +/- 10°, being fed through a digital cross-talk cancellation system
46	Binaural (Dual Stereo Dipole)
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48	Recording The Soundfield (TM) microphone provides 4 signals: 1 omnidirectional (pressure, W) and 3 figure-of-8 (velocity, X, Y, Z)
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53	High Order Ambisonics (HOA) As a complex time-domain waveform can be though as the sum of a number of sinusoidal and cosinusoidal functions, so a complex spatial distribution around a given notional point can be expressed as the sum of a number of spherical harmonic functions When the signals corresponding to spherical harmonics up to 3° order are summed with proper gains, one obtains a “virtual microphone” having a directivity pattern which can be very complex and highly directive
54	Spherical Harmonics
55	3^rd-order spherical microphone
56	Software for Ambisonics processing
57	Software for Ambisonics processing
58	Software for Ambisonics processing
59	Low-cost hardware for HOA Again, a PC with MADI interface is employed
60	Locations of loudspeakers
61	Psychoacoustics research Musical Food: sound quality analysis of Barilla - Mulino Bianco crackers and bread substitutes
62	Psychoacoustics research Listening tests with compilation of sound quality questionnaires
63	Psychoacoustics research Principal Component Analysis and correlation among physical and perceptual paramaters
64	Thanks to: Definzione contenuti espositivi e coordinamento: Alessandro Rigolli (per l'Istituzione Casa della Musica) Progettazione allestimento espositivo: Dario Costi e Simona Melli architetti Realizzazione allestimento espositivo: Leonardo Laboratorio di Costruzione S.n.c. via G. Giusti, 4/a Parma Gruppo Fallani S.r.l. via Pialoi, 100 Marcon (Ve) Tecno-fer S.r.l. v.le Basetti, 14 Parma Progettazione e realizzazione componente acustica (LAE): AIDA srl via G. Sicuri, 60/a Parma Genesis via Benedetta, 83 Parma Audiolink via Monte Prinzera, 17 Parma Sistemi informatici: IT City S.p.A. via Traversetolo, 36/a Parma Cablaggio: Albacom.Amps Telecomunicazioni S.p.A. Guglielmo srl via Livatino 9 Reggio Emilia Aet Parma Srl via Lelio Guidotti 15/A Parma Sistemi di sicurezza: BIEFFEDUE Elettronica Srl via Monte Aquila 10/a Corcagnano Parma Oggetti d’epoca: Hi Fi News di Cerioni Guido & C. Sas Borgo Onorato, 21 Parma Filmati: Mediavision s.n.c. viale Regina Margherita, 7/a Reggio Emilia Foto: R.C.R. e C. sas, stradello S. Girolamo, 19 Parma Foto: Mauro Ranzani Comunicazione: 0521-Agenzia di pubblicità e marketing b.go Antini, 4 Parma Ricerche storiche: Arch. Stefano Negri arch. Fabio Stocchi Maxischermi dimostrativi:: Bang & Olufsen via Mameli 9 Parma
65	Thanks to: The design and construction of these sound systems have been possible thanks to: Laboratory of Acoustics and Elettroacoustics (LAE) www.laegroup.org Parma