Course detail

Electroacoustics 2

FEKT-MPC-EL2Acad. year: 2023/2024

The course is focused on deepening theoretical knowledge in the field of sound waves, acoustic transmitters and receivers and physiological and psychological acoustics. It also deals with the systems of sound soureces and acoustic receivers, acoustic systems, loudspeaker and microphone models and their parameters, principles and technologies of lossy audio coding, spatial information coding and representation of 2D and 3D sound fields. Theoretical knowledge acquired in lectures is applied in computer exercises in the Matlab environment. The course ends with the elaboration of an individual project.

Language of instruction

Czech

Number of ECTS credits

6

Mode of study

Not applicable.

Guarantor

doc. Ing. Jiří Schimmel, Ph.D.

Department

Department of Telecommunications (UTKO)

Entry knowledge

The knowledge of basic physical laws is required as well as the knowledge of laws and quantities in electrical circuits, characteristics of electric circuit elements, circuit behaviour with inertia elements, periodical and non-periodical signal spectra, random variables and basic terms from the area of statistics, acoustics and electro-acoustics. Students who enrol on the course should be able to use instruments for the measurement of electrical quantities, sound recording and reproduction technology and sound level meters and have basic knowledge of Matlab.

Rules for evaluation and completion of the course

Evaluation of study results follow the BUT Rules for Studies and Examinations and Dean's Regulation complementing the BUT Rules for Studies and Examinations. Up to 30 points are awarded for the test in the computer exercises. Up to 10 points can be obtained for programming and defense of the individual project and it is necessary to get at least 5 points. The minimum scope of elaboration of computer exercises is determined by the annually updated decree of the subject guarantor. The final written exam is evaluated with a maximum of 40 points and for its successful passing it is necessary to obtain at least 25 points. The oral part of the final exam is evaluated 20 points and for its successful passing it is necessary to obtain at least 5 points.

Credit is awarded for completing all computer exercises in minimum scope and successful defense of the project. Other forms of checked instruction are specified by a regulation issued by the guarantor of the course and updated for every academic year.

Aims

The aim of the course is to deepen knowledge in the field of electroacoustics, physiology and psychology of hearing, acquisition and spatial representation of sound and their use in modeling electroacoustic devices, sound system design, processing, transmission and compression of audio signals.

On completion of the course, students are able to:
- describe characteristics of ideal sound sources, acoustic receivers and their systems,
- desribe linear models of loudspeaker nad microphone and their theoretical characteristics,
- explain the principles of frequency analysis of sound by human hearing and principles of spatial and directional hearing,
- explain the principles of lossy compression of audio signals, including the compression of spatial audio formats,
- explain the principle of sound field synthesis in a closed and open sound system using HRTF, Wavefield synthesis, ambisonia and VBAP,
- describe the use of lossy compression, coding of spatial information and sound field synthesis in compression algorithms of MPEG standards

Study aids

Not applicable.

Prerequisites and corequisites

Not applicable.

Basic literature

Bosi, Marina: Introduction to Digital Audio Coding and Standards. 2003. ISBN 1-4020-7357-7
Gardner, William G.: 3-D Audio Using Loudspeakers. 1998. ISBN 0-7923-8156-4
HILL, Geoff. Loudspeaker Modelling and Design: A Practical Introduction. 1. Routledge, 2018. ISBN 9780815361329.
Spanias, Andreas: Audio Signal Processing and Coding. 2007. ISBN 978-0-471-79147-8
Williams, Earl G.: Fourier Acoustics : Sound Radiation and Nearfield Acoustical Holography . 1999. ISBN 0-12-753960-3

Recommended reading

Not applicable.

Elearning

eLearning: currently opened course

Classification of course in study plans

  • Programme MPC-AUD Master's

    specialization AUDM-TECH , 2 year of study, winter semester, compulsory
    specialization AUDM-ZVUK , 2 year of study, winter semester, compulsory

Type of course unit

 

Lecture

26 hod., optionally

Teacher / Lecturer

doc. Ing. Jiří Schimmel, Ph.D.

Syllabus

  1. Sound waves: basic quantities and equations of the sound field, solution of the wave equation for plane, spherical and cylindrical waves, propagation of sound waves in a closed space.
  2. Acoustic transmitters: acoustic transmitter of the 0th, 1st and higher orders, rigid piston circular membrane, sound source systems, directional sound source.
  3. Loudspeakers: electromechanical analogy, radiation impedance, linear loudspeaker models, TS model, loudspeaker impedance, sound pressure generated by loudspeaker.
  4. Acoustic systems: lumped parameter models, electroacoustic analogy, loudspeaker enclosures, horns, headphones.
  5. Acoustic receivers: characteristics of acoustic receivers, gradient receivers, directional receivers, coincidence receiver systems, near-coincidence receiver systems, beamforming.
  6. Microphones: linear microphone model, proximity effect, directional and wave microphones.
  7. Physiological acoustics: auditory organ, frequency analysis in the inner ear, masking, critical bands, auditory filters, loudness and pitch.
  8. Principles of lossy audio coding: subband, transform and hybrid encoder, filter banks, psychoacoustic model, bit allocation.
  9. Spatial sound reproduction: directional and spatial hearing, stereophonic and multi-channel reproduction, object-based reproduction, coding of spatial information.
  10. 3D headphone audio: head-related transfer function and its measurement, physical and structural model.
  11. 3D audio for loudspeakers: vector-based amplitude panning, ambisonics, directional audio coding, wavefield synthesis.
  12. Lossy audio coding standards: MPEG-1 Audio, MPEG-2 Audio, MPEG-4 Audio, MPEG-D and MPEG-H 3D Audio standard. 

Exercise in computer lab

39 hod., compulsory

Teacher / Lecturer

doc. Ing. Jiří Schimmel, Ph.D.

Syllabus

  1. Use of Matlab in the course Electroacoustics 2
  2. Acoustic transmitters
  3. Loudspeakers
  4. Acoustic systems
  5. Acoustic receivers
  6. Test from computer exercises
  7. Microphone arrays
  8. Masking and auditory filters
  9. Subband codec
  10. Spatial audio coding
  11. 3D audio panning
  12. Test from computer exercises
  13. Consultation on individual project

Elearning

eLearning: currently opened course