1. Physics 1251 The Science and Technology of Musical Sound Unit 4 Session 37 MWF Synthesizers Unit 4 Session 37 MWF Synthesizers

2. Physics 1251Unit 4 Session 37 Synthesizers In your own words, describe what a synthesizer is and what it does. A synthesizer: is an electronic device; is an electronic device; is controlled by a player; is controlled by a player; produces electro-acoustic signals; produces electro-acoustic signals; simulates acoustic instruments; simulates acoustic instruments; generates novel and unique sounds. generates novel and unique sounds.

3. Physics 1251Unit 4 Session 37 Synthesizers 1′ Lecture: A Synthesizer is a player-controlled electronic device creating electro-acoustical signals that emulate other instruments or generate unique sounds. A Synthesizer is a player-controlled electronic device creating electro-acoustical signals that emulate other instruments or generate unique sounds. Notes played by acoustic instruments pass through four phases: (1) attack, (2) decay; (3) sustain; (4) release. (ADSR) Notes played by acoustic instruments pass through four phases: (1) attack, (2) decay; (3) sustain; (4) release. (ADSR) Realistic synthesis requires sound to change with time in pitch, frequency recipe, and amplitude during the ADSR phases. Realistic synthesis requires sound to change with time in pitch, frequency recipe, and amplitude during the ADSR phases. Synthesizers are either analog or digital. Synthesizers are either analog or digital. Synthesizers employ either additive (or subtractive) synthesis or frequency modulation (FM). Synthesizers employ either additive (or subtractive) synthesis or frequency modulation (FM).

4. Physics 1251Unit 4 Session 37 Synthesizers 80/20 A Synthesizer is a player-controlled electronic device creating electro- acoustical signals that emulate other instruments or generate unique sounds. What does that mean?

5. Physics 1251Unit 4 Session 37 Synthesizers 80/20 A Synthesizer is a player-controlled electronic device creating electro- acoustical signals that emulate other instruments or generate unique sounds. Synthesizer 44444444 ♩ ♩ ♩ ♩ ♩ ♩ ♩♩

6. Physics 1251Unit 4 Session 37 Synthesizers 80/20 A Synthesizer is a player-controlled electronic device creating electro- acoustical signals that emulate other instruments or generate unique sounds. Synthesizer Voltage V Current I I =V/R Ohm’s Law: R =V/I

7. Physics 1251Unit 4 Session 37 Synthesizers 80/20 A Synthesizer is a player-controlled electronic device creating electro- acoustical signals that emulate other instruments or generate unique sounds. Current Synthesizer Voltage + -+ -+ - + -

8. Physics 1251Unit 4 Session 37 Synthesizers 80/20 A Synthesizer is a player-controlled electronic device creating electro- acoustical signals that emulate other instruments or generate unique sounds. Synthesis or the Real Thing?

9. Physics 1251Unit 4 Session 37 Synthesizers ♪ The first modern synthesizer was produced by RCA in 1955. ♪ The Moog (rhymes with vogue) synthesizer was invented in 1965 by Robert Moog. First Moog Synthesizer

10. Attack Physics 1251Unit 4 Session 37 Synthesizers ♪Realistic synthesis requires emulation of realistic musical sounds. 80/20 Musical sounds are characterized by four phases: (1) attack; (2) decay; (3) sustain; (4) release; abbreviated ADSR. Decay SustainReleaseEnvelop

11. Physics 1251Unit 4 Session 37 Synthesizers 80/20 Synthesizers use analog or digital processing. Analog Sound Waves Pressure Voltage

12. Physics 1251Unit 4 Session 37 Synthesizers Digital 80/20 Synthesizers use analog or digital processing. Sound Waves Pressure Digital: 1000 0100 0010 0001 80/20 The amplitude of the waveform is digitized and expressed as a binary number.

13. Digital to Analog Conversion (DAC) Physics 1251Unit 4 Session 37 Synthesizers 0001 0010 0100 10001010 1 2 4 8 DAC (Concept) 11010011

14. Electronic Digital-to-Analog Conversion 1 1 0 0 1 1 1 0 1 1 1 1 1 0 0 1 1 1 1 0 1 0 0 1 0 1 1 0 0 0 0 0 0 0 0 1 0 0 1 1 1 1 0 0 0 1 1 0 0 0 1 1 0 0 0 1 0 0 0 0 Physics 1251Unit 4 Session 37 Synthesizers Input Number Output Voltage

15. Electronic Digital-to-Analog Conversion 1 1 0 0 1 1 1 0 1 1 1 1 1 0 0 1 1 1 1 0 1 0 0 1 0 1 1 0 0 0 0 0 0 0 0 1 0 0 1 1 1 1 0 0 0 1 1 0 0 0 1 1 0 0 0 1 0 0 0 0 Physics 1251Unit 4 Session 37 Synthesizers Input Number Output Voltage

16. Electronic Digital-to-Analog Conversion 1 1 0 0 1 1 1 0 1 1 1 1 1 0 0 1 1 1 1 0 1 0 0 1 0 1 1 0 0 0 0 0 0 0 0 1 0 0 1 1 1 1 0 0 0 1 1 0 0 0 1 1 0 0 0 1 0 0 0 0 Physics 1251Unit 4 Session 37 Synthesizers Input Number Output Voltage

17. Physics 1251Unit 4 Session 37 Synthesizers Additive Synthesis: The output signal is built up from a sum of harmonic signals. The output signal is built up from a sum of harmonic signals. Σ

18. Physics 1251Unit 4 Session 37 Synthesizers Frequency Modulation (FM) Synthesis: In FM Synthesis the frequency f o of the signal is modulated up and down with a frequency f FM. The vibration recipe contains peaks at f o ∓ n f FM. In FM Synthesis the frequency f o of the signal is modulated up and down with a frequency f FM. The vibration recipe contains peaks at f o ∓ n f FM. If f FM = f o, then one produces a harmonic series, f = m f o. Voltage Controlled Oscillator (VCO) f FM fofofofo

19. Physics 1251Unit 4 Session 37 Synthesizers Summary: A Synthesizer is a player-controlled electronic device creating electro-acoustical signals that emulate other instruments or generate unique sounds. A Synthesizer is a player-controlled electronic device creating electro-acoustical signals that emulate other instruments or generate unique sounds. Notes played by acoustic instruments pass through four phases: (1) attack, (2) decay; (3) sustain; (4) release. (ADSR) Notes played by acoustic instruments pass through four phases: (1) attack, (2) decay; (3) sustain; (4) release. (ADSR) Realistic synthesis requires sound to change with time in pitch, frequency recipe, and amplitude during the ADSR phases. Realistic synthesis requires sound to change with time in pitch, frequency recipe, and amplitude during the ADSR phases. Synthesizers are either analog or digital. Synthesizers are either analog or digital. Synthesizers employ either additive (or subtractive) synthesis or frequency modulation (FM). Synthesizers employ either additive (or subtractive) synthesis or frequency modulation (FM).