Engineering Acoustics

A tantárgy neve magyarul / Name of the subject in Hungarian: Műszaki akusztika

Last updated: 2019. február 6.

Budapest University of Technology and Economics
Faculty of Electrical Engineering and Informatics
Minor specialisation of Audio and Studio Technologies
Course ID Semester Assessment Credit Tantárgyfélév
VIHIMA11 1 2/1/0/v 4  
3. Course coordinator and department Dr. Fiala Péter,
4. Instructors

Dr Péter Fiala     associate professor    Department of Networked Systems and Services

Dr Péter Rucz     assistant professor Department of Networked Systems and Services

Dr István Koller    master teacher    Department of Networked Systems and Services

5. Required knowledge Mathematics, Physics
6. Pre-requisites
NEM ( TárgyEredmény( "BMEVIHIM226" , "jegy" , _ ) >= 2
TárgyEredmény("BMEVIHIM226", "FELVETEL", AktualisFelev()) > 0)

A fenti forma a Neptun sajátja, ezen technikai okokból nem változtattunk.

A kötelező előtanulmányi rendek grafikus formában itt láthatók.

7. Objectives, learning outcomes and obtained knowledge The aim of the subject is to get acquainted the students with the basic principles of acoustics, especially of technical acoustics, and their internal relationships; to present the processes taking place in acoustic systems; and to hand over the basic knowledge required for practical applications, measurements and acoustic design. The core of the subject is the field of audio, with special regard to acoustic transducers, their analysis and synthesis. Next to the physical principles of sound generation and recording, other subjects such as room acoustics as well as the control and reduction of airborne and structure-borne sound is also concerned. The subject forms the basis of successful acquirement of other subjects of the Minor Audio and Studio Technologies.
8. Synopsis Lectures
1.    Basic notions of acoustics: descriptors of airborne sound (sound pressure and particle velocity), logarithmic quantities (notion of decibels and applications). The wave equation of sound, solution for plane and spherical waves.
2.    Further characteristics of sound fields: the notion of acoustic impedance, acoustic intensity and specific impedance and their relationships.
3.    One-dimensional modelling of acoustic systems. Lumped parameter elements: acoustic mass, acoustic capacity and acoustic resistance.
4.    Longitudinal vibrations of rods, solution of the wave equation for low frequencies. Mechanical lumped parameter elements: spring, mass and resistance.
5.    Acousto-mechanical-electrical analogies and their applications. Potential, limitations and application possibilities of concentrated parameter vibro-acoustic models.
6.    Elementary radiators in acoustics: point source, line source and plane source. Notions, characteristics and calculations. Importance and calculation of the radiation impedance.
7.    Electromechanical transducers. The electrodynamic transducer: construction , operation, characteristics and calculation.
8.    Basic notions of speakers, their characterization and synthesis. Application of the most frequently used electrodynamic drivers in various speaker boxes.
9.    Construction, operation, main types, characteristics and application of microphones.
10.    Principles of sound propagation, reflection and absorption. Predominant parameters, calculation and design of sound insulating elements and systems.
11.    Basics of room acoustics. Acoustic characteristics of rooms, notion and calculation of sound decay and reverberation.
12.    Basic characteristics of condenser microphones, analogue circuit, band limitations. Measurement of very low sound pressures, noise analysis.
13.    Methods and tools of sound intensity measurements, based on the pressure gradient and of the Microflown particle velocity sensor principle. Analysis of accuracy of various methods.
14.    Sound pressure level meters, acoustic analyzers. Measuring methods of frequency response functions.

1.    Demonstrations of various sound fields. Calculation examples to shed light into the relationships of sound field characteristics.
2.    Simple calculations with lumped parameter acoustic models, application for a Helmholtz resonator (for example, what is the operating mechanism of the special bottle of the Hungarian whistling abricot brandy?).
3.    Application of analogies for simple dimensioning problems in vibro-acoustics, noise and vibration control.
4.    Synthesis of sources by using superposition of elementary sources, demonstration of radiation problems. (Example: how can the annoyance caused by the Sziget Festival in Óbuda and Angyalföld be reduced?)
5.    Calculation of the frequency response of a transducer. (What kind of speaker should I buy?)
6.    Aspects of selection of condenser measuring microphones. Calibration methods of microphones.
7.    Practical aspects of intensity measurements. Application of acoustic analyzers for the measurements of microphones and speakers.

9. Method of instruction Lectures and excercises, consisting of many demostrations.
10. Assessment a.     A szorgalmi időszakban:
Successful (grade 2) fulfilment of a written examination (NZH).
b.       A vizsgaidőszakban:
    Oral exam.
c.       Early exam is possible in the substitution period (first week after the lectures).

11. Recaps In case of insufficient grade or missing of the written examination :
1 substitute written examination in the lecture weeks, 1 extra substitute written examination in the substitution period (first week after the lectures).

12. Consultations After the lectures or on pre-arrengements.
13. References, textbooks and resources F. Fahy: Foundations of engineering acoustics. Academic Press, London, 2000.
14. Required learning hours and assignment
Kontakt óra42
Félévközi készülés órákra10
Felkészülés zárthelyire18
Házi feladat elkészítése 
Kijelölt írásos tananyag elsajátítása10
15. Syllabus prepared by Dr Fülöp Augusztinovicz     professor    Department of Networked Systems and Services
Dr. István Koller     master teacher    Department of Networked Systems and Services