THEREMIN

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THEREMIN
Theremin

• Mississippi State University
• Department of Electrical and Computer Engineering

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Team Members
Theremin
Douglas Beard dtb4_at_ra.msstate.edu
Way Beng Koay wk4_at_ece.msstate.edu
Dr. Raymond Winton Faculty Advisor
Jeffrey Jun-Fey Wong jw5_at_ra.msstate.edu
Micah Caudle Msc1_at_ece.msstate.edu
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Responsibilities
Theremin

• Douglas Beard
• Discrete Frequency Hardware

• Micah Caudle
• Pitch and Volume Control Hardware
• Tuner Out Circuit

• Way Beng Koay
• Discrete Frequency Hardware

• Jeffrey Jun-Fey Wong
• Output Stage
• Footswitch Circuit

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Background
Theremin

• Created by the Russian Inventor Leon Theremin in
  1919.

• First electronic instrument influencing Moog and
  pioneers in musical electronics.

• The thereminist does not actually touch the
  theremin except to mute it.

• Controlled by capacitance between hands to
  antennas. Placement of the hands relative to
  antennas controls this capacitance.

• Uses heterodyning to create audible frequencies
  from the difference of two high frequency
  oscillators.

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How Does It Work?
Theremin
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Motivation
Theremin
Currently

• Quality theremins are too expensive.
• 369-3,500

• Limited playing style prevents broad use.
• Horror Movies
• Sound Effects

• Too difficult to play well.
• No Physical Reference

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Problems
Theremin

• Continuous Pitch The theremin is a continuous
  pitch instrument like trombone or violin which
  makes staying in tune difficult. This fact makes
  theremin difficult to learn, but it also produces
  some desired effects.

• Continuous Volume Staccato playing or quick
  stops and starts are difficult with the theremin
  because of continuous volume.

• Lack of Reference Since the thereminist does
  not actually touch the theremin, the thereminist
  has no point of reference for notes and nothing
  to steady his or her hand.

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Solutions
Theremin

• Dual Mode Theremin The theremin will be able
  to switch from the original continuous frequency
  mode and a new discrete frequency mode.

• Foot Pedal A foot pedal will allow
  instantaneous mute and unmute in order to produce
  easier staccato.

• Tuning A reference for tuning will be provided
  for silently locating starting pitches and pitch
  verification during practice. Theremin will
  interface with common tuners.

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Design Requirements
Theremin

• Continuous/Discrete Frequency Control
• Switchable between playing the traditional
  continuous range and playing only distinct
  frequencies in selectable scales with error lt
  0.1.

• Tuning
• A small amplitude signal will always be present
  at the 1/4" tuner out jack to enable the
  performer to locate starting pitches and for
  pitch verification during practice.

• Precise Articulation
• A footswitch will connect to the theremin to
  enable the performer to quickly and easily
  articulate notes.

• Frequency Range
• A frequency range of four octaves with adjustable
  center frequency set to a default value of middle
  C at 262Hz.

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Continuous/DiscreteFrequency Control
Theremin
Fixed Oscillator
Variable Oscillator
Summing
Antenna
Switch
Discrete Frequency Controller
Volume Control Audio Output
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Front Panel Frequency Controls
Theremin
Key
Continuous
A
B
Chromatic
b

C
G
F
D
Discrete
E
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Tuning
Theremin
FLAT IN TUNE
SHARP
A . B C . D . E F .
G .
Sabine STX-1100
Theremin
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Theremin Modular Design
Theremin
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Test Specifications
Theremin
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Theremin
Aug Aug Sept Sept Sept Sept Sept Oct Oct Oct Oct Oct Nov Nov Nov Nov Nov Nov Dec Dec
Objective 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 4 5 1 2
Documentation
Presentation
Research
Design
Simulation
Prototype
Design Module A Pitch Control A Pitch Control A Pitch Control A Pitch Control A Pitch Control B Volume Control B Volume Control B Volume Control B Volume Control B Volume Control B Volume Control B Volume Control C Discrete Freq Controller C Discrete Freq Controller C Discrete Freq Controller C Discrete Freq Controller D Output Control D Output Control D Output Control D Output Control

Requirement
Test Spec
Design
Test Cert
Final
Preliminary Design Review
Design Review
A
B
C
D
A B
D
C
A B
D
C
Douglas Beard
Jeffrey Jun-Fey Wong
Way Beng Koay
Micah Caudle
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Theremin
References
1 J. Rothman, "Simple Theremin," Everyday
Practical Electronics, vol. 24, no. 9, September
1995. 2 B. Suits, "Physics of Music",
http//www.phy.mtu.edu/suits/notefreqs.html,
Physics Department, Michigan Technological
University, Houghton, Michigan, USA. 3 "Sabine
Professional Audio and Music Accessories
http//www.sabineusa.com/index.html, Sabine,
Inc., Alachua, FL, USA, August 2000. 4 E. J.
Schultz, A Simple Electronic Musical Instrument
The Theremin, Radio and Television News, pp.
84-86, October 1949. 5 A. Harrison, The
Wien-Bridge Theremin, http//home.att.net/there
min1/Wien/wien.html, October 1999. 6 L. E.
Garner, Jr., For That Different Sound, Music a
la Theremin, Popular Electronics, November
1967. 7 R. Moog, "Build the EM Theremin,"
Electronic Musician, pp. 86-100, February 1996.
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Theremin
References
8 R. Moog, "A Transistorized Theremin,"
Electronics World, vol. 65, no. 1, pp. 29-32,
125, January 1961. 9 G. Velasquez, "The Aria,"
Wescon/97 IEEE Conference Proceedings, pp.
527- 530, November 1997. 10 C. A. Balanis,
Antenna Theory Analysis and Design, John Wiley
Sons, Inc., New York, New York, USA, 1997.