Music 401C Spring 2022

Acoustics of Music

Dr. Andrew Schloss
Office: MacLaurin A177 Local: 7931
Office hours: Tuesday 4:30-5:30 pm or by appointment (call to confirm)

email: aschloss at uvic dot ca

NOTE: All emails pertaining to this class must have "MUS 401C" in the title.

Office: MacLaurin A172
Office hours:

Classes: MacLaurin A168: Tues, Weds, Fri 11:30 am

Text: The Science of Sound, third edition by Thomas Rossing. Addison-Wesley 2002.

on reserve: The Acoustical Foundations of Music by John Backus

The Physics and Mathematics of Waves An optional primer on the physics of sound. Assumes knowledge of calculus and some differential equations. Not required for this course, read only if you are interested!


quiz (1) 15%

homeworks (5) 25%

mid-term exam 25%

final exam 35%

We will cover most of parts I, II, III, IV, VI of Rossing in this course (18 chapters).

(Homeworks normally due on Fridays. Note that homeworks are the EXERCISES in the book)

Week 1 Introduction, basic physical principles, Vibrating Systems
3 January Reading: Rossing Chapter 1

Week 2 SHM, Modes of vibration, complex vibrations, vibration spectra, Fourier transform
9 January Reading: Rossing Chapter 2,3 (optional: Wolfenden article)

Week 3 Waves, propagation, reflection, refraction, diffraction, interference, linear superposition, Doppler Effect
16 January  HW #1 due: Rossing EXERCISES Chapters 1,2,3 (p19: 2,5,9,10 p37: 3,4,6 p58: 1-10)

Week 4 Resonance, standing waves, acoustic impedance
23 January  Reading: Rossing Chapter 4

Week 5 Hearing, psychoacoustics, psychophysics: Weber and Fechner's law, logarithms, critical bands, localization, Haas effect
30 January   HW #2 due: Rossing Chapter 4 (p73: 2,3,5,6,8) Reading: Rossing Chapter 5 

Week 6 QUIZ 1: FRIDAY, 9 Feb(Chapters 1-5)
6 Feb
  Reading: Rossing Chapter 6 Perception of loudness, the decibel, masking (forward and backward), origin of mp3 files

Week 7 READING BREAK (all week)
13 Feb    
Reading: Rossing Chapter 7

Week 8   Timbre, spectra of complex waveforms, beats, Helmholtz, pitch discrimination, jnd for pitch (in cents) and for amplitude (in dB).
20 Feb
   Time domain vs frequency domain (Reading: Chapter 8 optional)
Constructing a complex waveform in the time domain by adding rotating phasors (complex exponentials); for example the first 4 partials of a square wave:

Week 9 Cents, tuning, temperament
27 Feb   Reading: Rossing Chapter 9
Graphical representation of tunings
, Bach's scheme for the Well-Tempered Clavier
HW#3 due: Rossing Chapters 5,6,7 (p97: 1-6,p119: 1-5,p147: 1,2,4,8,10,11,12)

Week 10 Acoustics of stringed instruments -- violin bowing simulation, violin octet
6 March    
Reading: Rossing Chapter 10
(Reference) Chapters 3-9 review test)

Week 11 Brass and Woodwinds
13 March   Reading: Rossing Chapters 11,12

Week 12 Percussion and keyboard instruments
20 March   Reading: Rossing Chapter 13,14

HW#4 due: Rossing Chapters 9-12 (p190: 1,3,4,5,7,8,9, p223: 2, 3, 5,6,(8), p244: 1,4, p270: 4,5,6)
(HINT: Question 3 on page 223 can't be done without "eyeballing" figure 10.7 to see how much of the time is spent slipping vs being pulled by the bow)

Week 13 The Human voice: Speech, singing. Room acoustics
27 March   Reading: Rossing Chapters 15, 17, 23

Week 14 REVIEW and presentations
3 April HW#5 due: Rossing Chapters 13-15, 17, 23 (p308: 4,6, p333: 1,5, p353: 1,7, p396: 1,3, optional: p544: 1,5,6,7)
: Question 6 on p308 refers to figure 13.31, not 13.32

There will be an optional extra class (will include a review of Chapters 1-15) in A168: APRIL X, 2 PM

FINAL EXAM (Monday, APRIL 9, 2018 at 7 pm)

In-class demos:

SHM: Simulation of multiple masses

WAVES: reflection of pulse on a string
reflected pulses (fixed end = phase reversal, free end = no phase reversal)

Wave Interference

Fourier: Making Waves

longitudinal vs transverse waves (slinky)

standing waves

phase of driven oscillation at resonance

tuning fork modes

speaker phase demo

oscillator/beats demo

oscilloscope demo

realtime 3D spectrum (sndpeek)

instrument identification (removing or truncating attacks to obscure instrument identification)

whirling toy (harmonics -- use w/ tuned MSP patch)

music box (sympathetic vibrations vs resonance)

DSP programs, instrument modeling, SuperCollider, MSP

How audition works (3D simulation of auditory system)

Modes of a vibrating plate:

The consonant birdsong: Musican wren:


Auditory Demonstrations CD (JASA/Acoustical Society)

Clarinet with flute mouthpiece and vice-versa:

Clarinet made from carrot!

Guitar acoustics by Arkady Futerman