ECE Course Outline

ECE Course Outline


ECE Course Outline

ECE4xxx – 
Guitar Amplification and Effects  


ECE 3040 [min C] and ECE 3041*
  * Prerequisites indicated with an asterisk may be taken concurrently with ECE4xxx.
Catalog Description: 
Mathematical analysis, analog laboratory measurement, and DSP modeling of vibrating strings, electromagnetic pickups, vacuum tube amplifiers, solid-state distortion and swept filter effects, and loudspeakers.
No textbook specified.
<!– Probabilistic Methods of Signal and System Analysis (3rd edition), Oxford University Press, 1999. (required)


Topical Outline: 

Historical perspective
Acoustics of vibrating strings
  The 1-D wave equation
  Interpretation of pluck as initial condition
  Traveling waves
Electromagnetic pickups
  Physical principles
  Linear circuit models
  Effect of location
High voltage safety procedures
Vacuum tube properties
  Electrodynamic principles
  Small-signal and large-signal models
Vacuum tube amplifiers
  Biasing, gain, input/output impedance, frequency response
  Distortion characteristics
Solid-state distortion effects
  Germanium vs. silicon BJTs
  Overdriven transistor amplifiers
  Diode-based waveshaping circuits
Swept filter effects
  "Wah" pedals
  Allpass filters and "phaser" effects
  FETs as variable resistors
  Bucket-brigade devices and "flanger" effects
Loudspeaker modeling
Digital modeling
  Introduction to real-time DSP programming
  Simulation of dynamic systems with nonlinearities and time-varying parameters

Objective:&nbsp This class explores the fields of acoustics, electromagnetics, electronics, device physics, system and signal theory, and computer engineering through the specific platform of the electric guitar and its commonly associated amplifiers and effects devices. The distinction between these tools begins to break down, since amplifiers are often deliberately driven to distortion as an effect, and in the hands of a skilled and thoughful player, the various effects pedals musicians often play may be better thought of as part of the complete “instrument.” The guitars, amplifiers, and effects explored in this course are not just intriguing motivational examples for traditional ECE topics; we feel that they are technological and cultural artifacts worthy of study in their own right in the spectrum of systematic musicology. They are part of our history. We believe that Jimi Hendrix, wrestling his Fuzz-Faced Stratocaster in front of his Marshall amplifier stack, was a transcendent example of a cyberphysical system &mdash a beautifully unstable feedback loop of sweat, circuitry, and sound.

Grading:&nbsp Grades will be assigned based on performance on homework assignments and laboratory exercises. The homeworks, which are intended to hone analytical skills, will emphasize real circuits that have been used by real musicians, and not typical “textbook” problems. Laboratories will be integrated throughout the course.

Role in our program:&nbsp This class is designed to complement (i.e. be in a similar spirit of, but not overlap too much with) our other audio/music related classes such as ECE4445 Audio Engineering (originally developed by Marshall Leach, most recently taught by Allen Robinson), Bill Hunt’s special topics class on Musical Acoustics for the Creation of Musical Instruments, and my own class on Electronics for Music Synthesis. We hope that this class may offer another path to interface with the Georgia Tech Center for Music Technology, and also perhaps encourage new industry investment in the School of ECE.

References:&nbsp Because of the interdisciplinary nature of the course, we currently do not anticipate assigning any particular required text, since no single text encompasses all of the areas we want to explore at an appropriately deep level mathematical and engineering sophistication. We may draw material from some of the following references.