Course detail

Electroacoustics

FEKT-BPA-ELAAcad. year: 2024/2025

Acoustic environment, sound propagation, basic quantities and relations, energy transmitted by sound. Physiological acoustics, sound masking and its utilization in compression algorithms, directional and spatial hearing. Noise and its measurement. Room acoustics, room impulse response. Electromechanical and electro-acoustic analogy, acoustic materials and structures. Types and operation principles of electro-acoustic transducers. Microphones, practical design and measurement of characteristics. Loudspeakers, acoustic impedance and distortion, mechanical design, horn-loaded loudspeakers, headphones. Loudspeaker systems, types of loudspeaker enclosures, design and construction of loudspeaker systems and crossovers. Multichannel audio systems, basics of sound reinforcement. Stereo and multichannel techniques of sound pickup.

Language of instruction

English

Number of ECTS credits

5

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 knowledge of laws and quantities in electrical circuits, characteristics of electric circuit elements, circuit behaviour with inertia elements, periodical and non-periodical signal spectrum, random variables and basic terms from area of statistics.
The student who enrols the subject should be able to use instruments for measurement of electrical voltage, current, and resonant frequency, waveform generators and oscilloscopes.

Rules for evaluation and completion of the course

Evaluation of study results follows Rules for Studies and Examinations of BUT and Dean's Regulation to the Rules for Studies and Examinations of BUT. Up to 40 points is given for correct results and elaboration of all laboratory exercises. The minimal scale of elaboration of particular laboratory exercises and completive questions are specified by a regulation issued by the guarantee of the course and updated for every academic year. Up to 60 points is given for the final written examination and it is necessary to get at least 15 points for its successful completion. The exam consists of 10 groups of questions in the field of acoustics and electroacoustics according to the subject syllabus and one question is selected from each group.
It is mandatory to pass all laboratory exercises in regular or alternative terms to complete the course. Other forms of the checked instructions are specified by a regulation issued by the guarantee of the course and updated for every academic year.

Aims

The aim of the course is to make students familiar with the chain of processing acoustic signals from their origination through their transformation into electric signals and back to acoustic signals up to the listener's final perception.
Graduate of the course is able to:
- name basic acoustic quantities and their units,
- explain physiology of hearing including binaural auditory perception,
- employ sound level meters and use them for noise and electroacoustic measurements,
- describe room acoustic properties, demonstrate measurement of room impulse response and reverberation time, name materials and structures used for room acoustic treatment,
- categorize electroacoustic transducers and state their principles, properties and their use,
- categorize microphones, state their properties and designs, and demonstrate measurement of their characteristics,
- describe properties of designs used for unloaded and loaded loudspeakers, measure and calculate their parameters,
- design loudspeaker systems and measure their characteristics,
- name types of surround sound systems and describe their principle,
- name methods of multichannel sound pickup and explain their principles.

Study aids

Not applicable.

Prerequisites and corequisites

Not applicable.

Basic literature

Benson, K., B. Audio Engineering Handbook. McGraw-Hill, 1988. ISBN 0-07-004777-4 (EN)
SCHIMMEL, J. Electroacoustics - Laboratory Practices. Brno, VUT v Brně. 2015. p. 1 - 59. SCHIMMEL, J. Electroacoustics. Electroacoustics. Brno, VUT v Brně. 2015. p. 1 - 120. ISBN 978-80-214-5030-1.
SCHIMMEL, J. Electroacoustics. Brno, Brno university of Technology. 2015. p. 1 - 120. ISBN978-80-214-5030-1.
Streicher, R., Everest, F., A. The New Stereo Soundbook, 3rd ed. Audio Engineering Associates, 2006. ISBN 978-0-9665162-1-0 (EN)

Recommended reading

Not applicable.

Classification of course in study plans

  • Programme BPA-ELE Bachelor's

    specialization BPA-ECT , 0 year of study, winter semester, elective

Type of course unit

 

Lecture

26 hod., optionally

Teacher / Lecturer

doc. Ing. Jiří Schimmel, Ph.D.

Syllabus

1. Acoustic environment, basic quantities and relations, wave equation of sound propagation, energy transmitted by sound, sound spectrum. Types of acoustic fields.
2. Physiological acoustics, subjective and objective properties of sound, sound masking and its utilization in audio compression algorithms.
3. Directional and spatial hearing, 3D room simulation using headphones and loudspeakers.
4. Noise and its measurement, noise classes, loudness measurement according to Steven's and Zwicker's models.
5. Sound level meters, analyzers for electroacoustic measurements, calibration of measurement chain. Measurement of acoustic power and sound intensity.
6. Basics of room acoustics, geometric, wave and statistic models, room impulse response, measurement of reverberation time, objective parameters of listening rooms.
7. Electromechanical and electro-acoustic analogy, acoustic materials and structures.
8. Electro-acoustic transducer as the system, types and operation principles of transducers.
9. Gradient microphones, wave and combined microphones, design and measurement of characteristics.
10. Loudspeakers, acoustic impedance and distortion, mechanical design, horn-loaded loudspeakers. Types and design of headphones, measurement of characteristics.
11. Loudspeaker systems, types of loudspeaker enclosures, design and construction of loudspeaker enclosures and crossovers. Acoustic lenses.
12. Multichannel sound reproduction, basics of sound reinforcement.
13. Stereo and multichannel techniques of sound pickup. 

Laboratory exercise

26 hod., compulsory

Teacher / Lecturer

doc. Ing. Jiří Schimmel, Ph.D.

Syllabus

Getting familiar with the laboratory and the safety regulations, getting familiar with operating laboratory equipment.
Sound signal spectrum
Measurement of ear's own characteristics
Noise measurement and its evaluation
Room acoustics measurement
Measurement of binaural hearing characteristics
Test and compensatory practice
Measuring the frequency response of microphones
Measuring the impedance characteristic of loudspeakers
Design and simulation of loudspeaker system
Measuring the frequency and directional response of loudspeaker system
Measurement of acoustic intensity and power radiated by object
Test and compensatory practice