Electronic Sound Synthesis With Lira Landes

On December 5th Sound Museum Collective was luckily to have Lira Landes of Plastic Ivy come in to demystify how analog synths and waveforms occur. Below is an outline of the lecture she facilitated!

What is the nature of sound?

1. In order to understand how sound works electronically it is first necessary to grasp how it works acoustically, in the natural world.

• Oscillation: The back and forth motion of a source. (ie. Speakers)

• Waves: Sound is a wave that travels through a medium like air or water. This is the cause of a vibration in the air which in turn causes surrounding atoms a molecules to vibrate back and forth. The ripple effect continues and sound waves spread outward — Displacement waves and Longitudinal waves (the medium moves in the same direction the wave is moving)

Result: Air compresses and expands — sound waves are sometimes called pressure waves. Particles bunch together in some areas and spread out in others, creating areas of high pressure and areas of low pressure. • Microphones (diaphragm moving back and forth) > transfer to electrical signal (audio) • Eardrum (vibrating back and forth) > transfer to auditory perception

• Pitch: more vibrations per second = higher frequency and vice versa.

• Loudness: amplitude or intensity of waves

2. What about acoustic music?

• Standing waves - waves that don’t look like they’re traveling anywhere.

- Reflection and interference (Strings and pipes)

- Fundamental and overtones (relative loudness of harmonics = timbre) Instrumental Sound Production

• Generator (power source), Vibrator (movement), Resonator/Amplifier (tone and volume). - The voice, acoustic musical instruments

3. Analog Subtractive Sound Synthesis

• Identical method of sound production through the use of individual electronic devices called modules that are interconnected to form a system.

- Oscillators —Waveforms (Harmonic Character), Frequency

- Filters — Sculpting of rich source through elimination or control of harmonic presence to further develop harmonic character — Timbre - Amplifiers — Dynamic loudness control

- Controllers — Envelope Generators, Step Sequencers - Modulators — Low Frequency Oscillators (LFOs), Sample & Hold Generators, Step Sequencers

Presented by Lira Marie Landes — liramarielandes@gmail.com