Transcript A Brief History of Electronic Music and its Theory

A Brief Exploration of Electronic
Music and its Theory
By: Zac Changnon
Sound Generation
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There are two very general techniques for
creating sound electronically:
 Synthesis
 Sampling
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Both are widely used today and have
undergone many evolutions from their early
days.
Synthesis
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Electronic synthesis is the fabrication of sound from varying
(oscillating) electronic signals, or a simulation of such signals.
Many different kinds of synthesis/synthesizers:
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Analog
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Digital
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Additive
Subtractive
FM (frequency modulation)
Granular
Wavetable
Software Modeling/SoftSynth
…and more
More Classifications
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Polyphonic/Monophonic
 Indicates
whether a synthesizer can play multiple
notes at once, or just one.
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Modular/Non-modular
 In
modular synths, each piece of the equipment (the
sound generators, filters, amplifiers, and so on) are
literally separate blocks that can be wired together in
different ways.
How it Works
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Basic analog synthesis is based on the
manipulation of basic waveforms, like a sine
wave:
The horizontal axis is time, while the vertical axis is voltage. This
oscillating voltage is applied to a speaker, which turns it into sound. It is
probably amplified first.
How it works, cont’d
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Higher notes correspond to a higher frequency wave:
•Lower notes correspond to lower frequency waves:
How it works, the end
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Most analog synthesizers operate
on at least two wave forms
simultaneously. These waves are
combined in various waves to
produce the wave which makes the
final sound. In subtractive
synthesis, two waves are subtracted
to give a final sound wave, like so:
After the generation of the wave, many effects are often applied between the
oscillators and the speakers. Frequency filters can dampen or add warmth to
sound, amp envelopes can alter the attack and decay rates, and low frequency
oscillators and other effects can be applied to add color to the overall sound.
A brief history of synthesizers
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The earliest synthesizers used simple oscillating
circuits and date as far back as 1876.
Synthesizers in recorded and popular music,
however, did not come into play until much later.
One of the most famous early synthesizers to
gain some notoriety was Robert Moog’s “Moog”
modular synthesizers, which he first built in
1963.
A Moog
History, the end
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Synthesizers have changed a great deal in both sound and appearance
since the Moog.
Today, analog synthesis is often modeled on a computer by a software
synthesizer, or “SoftSynth,” like Propellerheads’ “Rebirth”, shown below:
Sampling
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Sampling can refer to many things, but in this
case it refers to the use of sampler, a digital
device which can play back (usually short)
samples of just about anything, at various
pitches by speeding up for slowing down the
sound (adjusting its frequency).
When connected to a keyboard, a musician can
play whatever sounds are loaded into the
sampler.
Sampling
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Sampling has a variety of applications. Some
sophisticated sample libraries exist which allow
a musician to obtain, for example, a very realistic
orchestral sound with only a keyboard and a
sampler.
This is one of the reasons sampling is so
widespread today; it allows one musician to
accurately simulate a wide variety of nonelectronic instruments.
Sampler Example
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One of the biggest players in the sampler
market for years has been Akai. This is what
their S3200 rack sampler looks like:
Modern Samplers
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Like synthesis, sampling is a practice that has lately been moving more and more
onto computers, away from dedicated hardware like the Akai. An extremely
powerful (and expensive!) example is Nemesys’ GigaStudio software sampler:
Sound Samples
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Simple Sine Wave Tone:
•Simple sine wave musical phrase:
•The same phrase, with a subtractive sawtooth and some filtering:
•And some simple background instruments and harmony, and we get:
References
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http://www.propellerheads.se
http://www.udel.edu/idsardi/sinewave/sinewave.html
http://www.obsolete.com/120_years/
Propellerheads’ Reason documentation
http://www.code404.com/synths/akai.html
http://www.soundforge.com/download/freewallpaper.asp
http://www.sospubs.co.uk/sos/nov00/images/gigastudio1
.l.gif
http://profs.sci.univr.it/~dafx/FinalPapers/pdf/Chowning.pdf