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Scheda Riassuntiva
Anno Accademico 2020/2021
Scuola Scuola di Ingegneria Industriale e dell'Informazione
Insegnamento 051489 - ROOM ACOUSTICS
Docente Cairoli Maria
Cfu 10.00 Tipo insegnamento Corso Integrato

Corso di Studi Codice Piano di Studio preventivamente approvato Da (compreso) A (escluso) Insegnamento
Ing Ind - Inf (Mag.)(ord. 270) - MI (263) MUSIC AND ACOUSTIC ENGINEERING*AZZZZ051489 - ROOM ACOUSTICS
Ing Ind - Inf (Mag.)(ord. 270) - MI (474) TELECOMMUNICATION ENGINEERING - INGEGNERIA DELLE TELECOMUNICAZIONI*AZZZZ051489 - ROOM ACOUSTICS
Ing Ind - Inf (Mag.)(ord. 270) - MI (481) COMPUTER SCIENCE AND ENGINEERING - INGEGNERIA INFORMATICA*AZZZZ051489 - ROOM ACOUSTICS

Obiettivi dell'insegnamento

The course is compound of the integration of two modules, MODULE 1: FUNDAMENTALS OF ROOM ACOUSTICS, and MODULE 2: ACOUSTICS OF LISTENING SPACES, which provides basic knowledge and application rules for the acoustic design of closed spaces. 

MODULE 1: FUNDAMENTALS OF ROOM ACOUSTICS

This course aims to provide the basic knowledge and tools that are needed for the analysis of the various stages of acoustic spatialization in enclosures, from generation; to propagation; to reception; to perception; in various human activities. This course will enable students to gather an in-depth understanding of acoustics phenomena in encosures (buildings, auditoria, etc.) and, in particular, to understand definitions and physical concepts behind the various related acoustic features. Physical modelling and mathematical formulation for analysing the sound will be also covered.

MODULE 2: ACOUSTICS OF LISTENING SPACES

This course is aimed at acquiring the necessary knowledge in acoustics for the design of acoustic environments (buildings, auditoria, listening rooms, etc.) in compliance with the requirements set forth by the community and users. The acquired competence includes understanding the impact of noise from internal and external sources and the use of theoretical and empirical methods to design environment with satisfying sound insulation against noise. Physical modelling and mathematical formulation for analysing room acoustics quality (i.e. indoor sound quality) will be also covered.


Risultati di apprendimento attesi

MODULE 1: FUNDAMENTALS OF ROOM ACOUSTICS

The students will acquire:
- Knowledge of basic theory on sound generation and propagation;
- Knowledge of sound propagation in rooms, sound perception, acoustic regulation and sound absorbents;
and will develop the following skills:
- they will be able to understand and analyse acoustic phenomena in buildings;
- they will be able to understand the physical background and be ready to take in new theories that will be needed in the future.

MODULE 2: ACOUSTICS OF LISTENING SPACES

Students are expected to acquire:
- Knowledge of basic acoustic theory on sound quality indicators for rooms;
- Knowledge of principles of room acoustics design
Students are expected to develop the following Skills:
- develop the ability of critical analysis of acoustics phenomena in buildings;
- learn how to design relevant solutions for separating structures with respect to impact sound and airborne sound including flank transmission;
- learn how to design geometry, furnishing and surfaces in rooms to get good room acoustic conditions for different room utilization (from offices to concert hall).


Argomenti trattati

MODULE 1: FUNDAMENTALS OF ROOM ACOUSTICS

Oblique planar wave in a finite volume limited by perfectly rigid surfaces: vibrations in the cavity, frequencies and natural modes of the room (axial, tangential, oblique).
Absorption influence on the vibration modes of the room, damped vibration and resonance peaks. Research of natural frequencies for a free damped vibrational motion. Forced vibration: the reverberant field as a linear combination of the dumped natural motions. Reverberant field: the transient attack, steady state, the sound tail.
Diffuse sound field: hypothesis, sound intensity on the boundary as function on energy density, mean free path e time between two reflections. Sound energy balance equation: split contribution of direct and reverberant fields
Steady state solution: total energy density function of equivalent absorption area; reverberant field energy density function of room index. Energy density decay, assumption of continuity of the reflections, the Sabine equation for T60. The energy density of the hypothesis of discontinuity reflections: Eyring equation for T60. SPL Difference, normalized value.
Acoustic human perception: phone diagram and A-scale correction for dBA. Sound Levels
Building Acoustics: Buildings sound protection; impact sound and air born sound; noise from HVAC systems.
Design of sound protections from outdoor and indoor air borne sound, from impact sound.
Room sound quality: sound absorption, measurement of sound absorption: impedance tube , reverberant room, Rating of sound absorption, sound absorption systems, Helmholtz Resonators and hollowed panels
Geometrical acoustics: reflection, diffraction and diffusion. Sound diffusers, acoustic mirrors.
Geometrical Room Acoustic: fundamentals
Modelling Room Acoustics performance
Room acoustics design principles.

MODULE 2: ACOUSTICS OF LISTENING SPACES

- Geometrical room acoustics
The range of wavelengths in geometrical Room Acoustics. Fresnel Zones.
Sound reflections from plane surfaces: the single Source Image, source Images of higher Order in a rectangular room, extension to three dimensions.

- Subjective room acoustics
Some general remarks on reflections and echoes, the perceptibility of reflections, echoes and coloration.
Early energy: Definition, Clarity Index, Speech Transmission Index. Reverberation and reverberance, Sound Pressure Level, Strength Factor, Spaciousness of Sound Fields, assessment of concert hall acoustics.

- Measuring techniques in room acoustics

- Room acoustics modeling
Design considerations and design procedures.
Direct sound, examination of the room shape with regards to the reflections, acoustical scale models, computer simulation, auralisation.

- HVAC Noise


- Theatre Acoustics in historical typologies
greek and roman period, early christian period, romanesque period, gothic period, baroque period, origins of sound theory, classical period, romantic period, beginning of modern acoustics, twentieth century

- Concert Halls and Opera Houses

 


Prerequisiti

MODULE 1: FUNDAMENTALS OF ROOM ACOUSTICS

In-depth knowledge of Calculus and linear algebra are required, with reference to complex numbers, derivatives, integrals, ordinary and partial derivatives equations, and matric operations. Knowledge of continuum mechanics basic principia and constitutive laws is warmly advised.

MODULE 2: ACOUSTICS OF LISTENING SPACES

Students are required to have attended "Module 1: Fundamentals of Room Acoustics".
Students are warmly encouraged to first attend "Fundamentals of Acoustics".


Modalità di valutazione

MODULE 1: FUNDAMENTALS OF ROOM ACOUSTICS

Final written and oral examination on the main course topics. In the written examination, the student has to answer to four open questions aiming to assess the ability of:
• understanding and analysing acoustic phenomena;
• understanding and analysing basic acoustic phenomena in buildings;
Correction and discussion on the written answers constitute the oral examination.

MODULE 2: ACOUSTICS OF LISTENING SPACES

Final written and oral examination on the main course topics. In the written examination, the student has to answer to four open questions aiming to assess the ability of:
• understanding and analysing complex acoustic phenomena in buildings;
• proposing solutions for the acoustics design of closed spaces according to their final destination.
Correction and discussion on the written answers constitute the oral examination.

 


Bibliografia

Forme didattiche
Tipo Forma Didattica Ore di attività svolte in aula
(hh:mm)
Ore di studio autonome
(hh:mm)
Lezione
65:00
97:30
Esercitazione
35:00
52:30
Laboratorio Informatico
0:00
0:00
Laboratorio Sperimentale
0:00
0:00
Laboratorio Di Progetto
0:00
0:00
Totale 100:00 150:00

Informazioni in lingua inglese a supporto dell'internazionalizzazione
Insegnamento erogato in lingua Inglese
Disponibilità di materiale didattico/slides in lingua inglese
Disponibilità di libri di testo/bibliografia in lingua inglese
Possibilità di sostenere l'esame in lingua inglese
Disponibilità di supporto didattico in lingua inglese
schedaincarico v. 1.6.5 / 1.6.5
Area Servizi ICT
27/09/2020