Learning objectives
Knowledge and understanding:
Basics of Acoustics, starting form physical quantities and going up to the usage of a modern digital sound level meter.
Applying knowledge and understanding:
The course is tailored to practical application, not to theoretical knowledge. Great emphasis is given to measurement methods, simple computations performed in Excel, and solution of practical problems. The student will learn to use the decibel scale, to “think in decibels”, and to perform the common math operations on dB values.
Making judgments:
In the whole course the judgment method is always based on human listening experience, not on numerical evaluation of the results. Acoustics is a perceptual science, and the final judgement can only by given by our hearing system, and not by means of “objective” numerical quantities. The students are consequently trained to listen and evaluate perceptually the most relevant acoustical effects, such as frequency-domain filtering, reverberation, echo, noise contamination, etc.
Communication skills:
The goal of this course is not, definitely, to train the students to perform as actors on stage. However, a significant part of the course is devoted to the study of the verbal and musical communication between performers and audience. In this part of the course, the students learn some tricks employed by professional actors and musicians, and become skilled in diagnosis and correction of communication problems due to room acoustics, improper design of the electro acoustical systems, or improper use of them by the performers and the audience.
Prerequisites
None
Course unit content
Nature of sound and physical quantities.
Decibels and sound level meters.
Sound propagation outdoors.
Sound propagation indoors.
Law and regulations concerning acoustic health protection at the workplace.
Full programme
The most important acoustical quantities: sound pressure, particle velocity, sound intensity, sound energy density, sound power.
The decibel scale applied to these 5 acoustical quantities.
Usage of decibels, calculations in dB.
Simplified calculation of sound propagation outdoors and indoors.
Interaction between a sound wave impinging over a wall: definition of the reflection, absorption and transmission coefficients.
Apparent sound absorption coefficient, sound reduction index.
Materials for sound absorption and sound insulation.
Typical spectral shape of absorption and sound reduction.
Reverberation, the Sabine's formula.
Measurement of the reverberation time.
Measurement of the apparent sound absorption coefficient.
Measurement of the sound reduction index.
Passive acoustical requirements of buildings, the Italian law.
Simplified evaluation of sound quality in concert halls, auditoriums and cinemas.
Noise at the workplace.
Bibliography
http://download.rockwool.it/media/74935/acustica%20in%20edilizia.pdf
Teaching methods
Frontal lessons (which are videorecorded during the exposition).
Numerical exercises taught in class (not videorecorded).
Experiments with measurement instruments, in class and outdoors.
Assessment methods and criteria
In-class tests at the end of each block.
Who do not reach a sufficient score with in-class tests must make a written exam test.
A final oral question on theory for everyone.
Other information
For a detailed plan of lessons, look here:
http://www.angelofarina.it/Acust-Illum-2017.htm
