Course detail

Audio Electronics

FEKT-BPC-AUDAcad. year: 2024/2025

Students become familiar with fundamentals of analog and digital low-frequency and audio signal, then with functionality and design of the pre-amplifiers, correction amplifiers, power amplifiers and filters. The course continues by explanation of sampling, quantization and coding in the area of audio with principles of the audio compression. Emphasis is put on explanation of principles of source coding, error corrections and methods for suppression of the signal degradation with record and playback. Students acquire knowledge of the methods for record and playback in the systems without and with reduction of the bit rate of the audio.

Language of instruction

Czech

Number of ECTS credits

Mode of study

Not applicable.

Guarantor

prof. Ing. Tomáš Kratochvíl, Ph.D.

Department

Department of Radio Electronics (UREL)

Entry knowledge

Students registering for the course should be able to explain the basic principles of analog and digital signal processing and function of the basic semiconductor units and amplifiers of the signal. Generally, the knowledge of the Bachelor's degree level is required. Work in the laboratory is subject to a valid qualification of "instructed person", which students must obtain before starting classes. Information on this qualification can be found in the Dean's Directive Acquainting Students with Safety Regulations.

Rules for evaluation and completion of the course

During the semester, students can obtain up to 30 points for their active work in laboratory. The final exam is awarded by up to 70 points.
The content and forms of instruction in the evaluated course are specified by a regulation issued by the lecturer responsible for the course annually.

Aims

Lectures are aimed at presenting the methods and technical means for processing, transmission and archive of the sound and audio signals in the area of digital low-frequency technique and audio electronics.
The graduate is able to:
- explain principles of analog and digital low-frequency and audio signal transmission
- describe sources and sinks of low-frequency and audio signal
- design appropriate pre-amplifier, correction amplifier, power amplifier of audio filter
- explain principles of sampling, quantization and coding of the sound and audio signals
- explain principles of bit rate compression of the digital sound and audio signals
- characterize system for the record and playback without and with audio compression
- measure parameters of analog and digital audio system or amplifier

Study aids

E-learning BUT, course BPC-AUD: https://moodle.vut.cz/course/view.php?id=268602

Web BUT, course BPC-AUD: https://www.vut.cz/studenti/predmety/detail/268602

Prerequisites and corequisites

Not applicable.

Basic literature

KOTISA, Z., VORÁČEK, V. NF zesilovače 1 - 4 díl. BEN - technická literatura, Praha, 2001-2006. ISBN 978-8073000301, 978-8073000530, 978-8073000653, 978-8073002114. (CS)
METZLER, B. Audio Measurement Handbook. Audio Presision, Inc., 1993. Audio Precision document number 0058.0003 r1. (EN)
POHLMAN, K. C. Principles of Digital Audio (Sixth Edition). McGraw-Hill, 2010. ISBN 978-0071663465. (EN)
ŠŤÁL, P. Výkonové audio zesilovače pracující ve třídě D. BEN - technická literatura, Praha, 2008. ISBN 978-8073002305. (CS)
WIRSUM, S. Abeceda nf techniky. BEN - technická literatura, Praha, 2003. ISBN 978-8086056265. (CS)

Type of course unit

Lecture

26 hod., optionally

Teacher / Lecturer

prof. Ing. Tomáš Kratochvíl, Ph.D.

Syllabus

1. Low-frequency signals, transmission and recording, processing and reproduction of audio.
2. Principles of electroacoustics and electroacoustic transducers - microphones and loudspeakers.
3. Classes and properties of amplifiers for low-frequency electronics (A, AB, B, D, T).
4. Preamplifiers for audio, input switching, physiological volume control.
5. Correction amplifiers and multi-band filters, depth and height correction, equalizers.
6. Final and power amplifiers, digital amplifiers with PWM modulation and ZV.
7. Digital processing of low-frequency signals, A/D with D/A converters, DSP.
8. Digital recording without data flow reduction (PCM, CD-Audio, SACD, DVD-Audio).
9. Digital recording with data flow reduction (MiniDisc, MPEG, Dolby Digital, DTS).
10. The principle of audio signal compression (MP3, ACC, WMA, OGG, ATRAC and others).
11. Standards for DAB/DMB digital radio broadcasting.

Laboratory exercise

26 hod., compulsory

Teacher / Lecturer

prof. Ing. Tomáš Kratochvíl, Ph.D.
Ing. Jan Kufa, Ph.D.

Syllabus

1. Input audio amplifier with adjustable sensitivity and RIAA correction.
2. Depth and height correction amplifier with physiological correction.
3. Digital power amplifier in class T with PWM.
4. Stereophonic active crossover for satellites and subwoofer with adjustable frequency.
5. The principle of a digital power amplifier in class D and PWM modulation.
6. Digital multi-band equalizer and limiter for audio signal controlled by PC.
7. A/D and D/A conversion of a low-frequency signal with optional conversion parameters.
8. Measuring the D/A converter of a CD player with an Audio Precision audio analyzer.

VUT

Faculties

University Institutes

Parts

Audio Electronics

Type of course unit