### Topics and Notes Summary (last update 11/14/2018):

DATE Comment
Nov. 16 (Fri)

Loudspeakers, start audio electronics .

Nov. 14 (Wed) Exams returned; discussion of authoritative references
Nov. 12 (Mon) Veterans Day Holiday (no MSU classes this day)
Nov. 9 (Fri) Exam #2 in class.
Nov. 7 (Wed)

Microphones, start loudspeakers, exam review.

Assigned: Course term papers:

Nov. 5 (Mon) Transducers: microphones and loudspeakers (cont.)
Nov. 2 (Fri) TOUR of Montana PBS studios.  MEET in the upper lobby of the Visual Communications Building at noon (do not go to the regular classroom).
Oct. 31 (Wed)

D2L Quiz 5 assigned (due by class time on 11/9/18).

Transducers:  microphones and loudspeakers .

Transducer notes

Reminder:  mid-term #2 in class on Fri. Nov. 9.  Example "practice exam."

Oct. 29 (Mon) Sabine equation examples (cont.)
Oct. 26 (Fri) Sabine equation and reverberation estimation.
Oct. 24 (Wed) Sound isolation and environmental acoustics (cont.)
Oct. 22 (Mon)

Environmental and architectural acoustical considerations (Chapter 13, then Chapter 12).

Determining sound transmission class (STC), and example wall partitions.

Oct. 19 (Fri) No class (instructor out of town)
Oct. 17 (Wed) Guest Lecture: Prof. Ross Snider
Oct. 15 (Mon)

Computer piston radiator homework due at the start of class.  NOTE: special due date extension granted until noon on Tuesday 16 Oct.

Oct. 12 (Fri)

Strengths and weaknesses of the human hearing system.

Note on computer homework assignment: Question about the off-axis angle of the 4 cm driver as a function of the observation angle, theta.

One way is to think of it as a two vector problem.  Vector #1 is the axis of the 4 cm driver and remains fixed, while Vector #2 is the "r4" vector from the center of the 4 cm driver down to the observation arc 2 meters from the lower driver.

Choose the origin (0,0,0) to be at the center of the 4 cm driver.  Then the axis vector Vector #1 can be represented (x, y, z) as (2,0,0), and the Vector #2 is the position on the observation arc, represented by
( 2*cos(theta12), 2*sin(theta12), -0.2 )  .

So you have two vectors as a function of theta12, and need to find the angle between those vectors, which is the off-axis angle for the 4 cm driver. Recall that the vector cross product relates the vectors and the angle between them, gamma.   | V1  x  V2 | = |V1| |V2| sin(gamma)  .   See if you can use this viewpoint and the Cartesian cross product calculation to find the angle information you need.

Oct. 10 (Wed)

Anatomy and function of the ear (cont.)      .

Oct. 8 (Mon)

Start physiology and psychology of human hearing (ch. 11). Hearing system:  frequency response of the ear. .

Computer homework problem assigned. Due at the start of class on 10/15/18.

Oct. 5 (Fri) No class this day (instructor out of town)
Oct. 3 (Wed)

Finish plane piston model;

Quiz #2 assigned on D2L. Due by class time on Oct. 10.

Oct. 1 (Mon)

Return exams.

Plane circular piston:  near field on-axis and far field off-axis.

Sept. 28 (Fri) Exam #1 in class.
Sept. 26 (Wed) "Simple source" model for sources with ka <<1.  Start consideration of plane circular piston model for loudspeaker driver.
Sept. 24 (Mon)

Review for Exam 1, to be held in class on Friday, Sept. 28. Coverage of Chapter 1, Chapter 5, and perhaps one question on Chapter 7 material. Exam is open book and open notes. Bring a calculator and pencil.

Spherical sound sources and acoustics of a small pulsating sphere model.

Sept. 21 (Fri)

Begin Chapter 7: radiation and reception of acoustic waves

Spherical sound sources and acoustics of a small pulsating sphere model.

Sept. 19 (Wed)

Decibel and weighting functions.

Notes on the Decibel Scale for engineering

Reminder:  D2L quiz due by class time.

Assignment: practice problems 5.12.35.12.12, and 5.13.2, from Kinsler and Frey.

Sept. 17 (Mon) Spherical waves, complex specific acoustic impedance.
Sept. 14 (Fri) Speed of sound experiment.  Spherical waves and acoustic impedance.
Sept. 12 (Wed)

Ch. 5 (cont.): linear acoustic wave equation, plane waves, particle speed, and specific acoustic impedance.

Assignment: Practice problems (not collected) 1.13.3 (note that a “t” is missing in the cos argument)1.15.75.2.4, and 5.6.2 .

D2L quiz #2 assigned:  two attempts by class time on 9/19/18.

Sept. 10 (Mon)

Linear acoustic wave equation (cont.)
Sept. 7 (Fri) The linear acoustic wave equation:  symbols and fundamentals.

Assignment:  Read Chapter 5 of the K&F textbook.

Sept. 5 (Wed)

Damped oscillators, Driven oscillators, and electrical analogies.

Reminder:  D2L quiz due by 11:30PM on Friday.

Sept. 3 (Mon)

No class this day:  Labor Day holiday

(University Holiday--no classes, offices closed).

Aug. 31 (Fri)

No class this day: instructor out of town.

Assignment: Practice Problems #1: three problems from the K&F text:  1.3.2, 1.3.3C, 1.6.1 .

Read and understand Chapter 1 of the K&F textbook, then work on the homework #1 practice problems. Your problem solutions will NOT be collected.  These are simply practice problems for your own preparation.

There is a D2L quiz that will go active at 10AM on 9/4/2018.  Between that time and 11:30PM on Friday, September 7, 2018, you have TWO attempts at the quiz.  Your Quiz 1 score will be the higher of your two attempts.  Each attempt is allowed one hour, although it should not take that long.

Aug. 29 (Wed)

Basic units and acoustical quantities.  Review of simple oscillators.

Assignment: Read Chapter 1 of Kinsler and Frey.

Aug. 27 (Mon)

First class meeting at noon in Cheever 214.

EELE 417 course introduction and some listening experiments.  Go over the syllabus and course expectations/goals/policies.