Low-frequency and Audio Electronics
FEKT-CNFEAcad. year: 2019/2020
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.
Learning outcomes of the course unit
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
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.
Recommended optional programme components
Recommended or required reading
WIRSUM, S. Abeceda nf techniky. BEN - technická literatura, Praha, 2003. ISBN 978-8086056265. (CS)
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)
TOMAN, K. Reproduktory a reprosoustavy I. Dexon, Karviná, 2001. ISBN 859-1459280805. (CS)
ŠŤÁL, P. Výkonové audio zesilovače pracující ve třídě D. BEN - technická literatura, Praha, 2008. ISBN 978-8073002305. (CS)
POHLMAN, K. C. Principles of Digital Audio (Sixth Edition). McGraw-Hill, 2010. ISBN 978-0071663465. (EN)
TALBOT-SMITH, M. Audio Engineer's Reference Book, Second Edition. Focal press, 1999. ISBN 978-0240516851. (EN)
METZLER, B. Audio Measurement Handbook. Audio Presision, Inc., 1993. Audio Precision document number 0058.0003 r1 (EN)
Planned learning activities and teaching methods
Teaching methods include lectures and practical laboratories. Course is taking advantage of e-learning (Moodle) system.
Assesment methods and criteria linked to learning outcomes
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.
Language of instruction
1. Low-frequency and audio signals, transmission and recording, audio processing.
2. Fundamentals of electroacoustics and transducers - microphones and speakers.
3. Low-frequency and audio amplifiers characteristics (class A, AB, B, D and T).
4. Audio preamplifiers, input selectors, loudness perception, volume control.
5. Bass/mid/treble control and audio filters, graphics and parametric equalizers.
6. Power amplifiers, digital class D amplifiers with Pulse Width Modulation control.
7. Digital audio and signal processing, ADC and DAC converters, DSP processing.
8. Digital audio recording without compression (PCM, CD-Audio, SACD, DVD-Audio).
9. Digital audio recording with compression (MiniDisc, MPEG, Dolby Digital, DTS).
10. Fundamentals of audio compression (MP3, ACC, WMA, OGG, ATRAC etc.).
11. Digital audio and multimedia broadcasting DAB/DMB.
1. Audio preamplifier with the RIAA correction and variable sensistivity.
2. Bass and treble control and Baxandall tone stack.
3. Digital class D and T power amplifier.
4. Active cross-over with separation to subwoofer and 2 way speaker satellites.
5. Fundamentals of digital class D power amplifier with PWM control and modulation.
6. Digital graphics equalizer and limiter with ADC and DSP and PC control.
7. ADC and DAC for audio with adjustable quantization and sampling frequency.
8. Compact Disc Audio DAC and audio measurements using Audio Precision analyzer.
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.
Specification of controlled education, way of implementation and compensation for absences
The content and forms of instruction in the evaluated course are specified by a regulation issued by the lecturer responsible for the course annually.