Module Synthesis - Basic

1. Explain the usage of the 5 most important
synthesis modules: Oscillator, Filter, Amplifier,
Envelope, and LFO.
My name is Sebastian La Rocca, I`m from Buenos Aires
Argentina. I`m a musician composer. This lesson is for week 6 of
Introduction to Music Production at Coursera.org.
The Modular Synthesis consists in these five building blocks:
Oscillator, Filter, Amplifier, Envelope, and LFO that are connected
together. We can connect these modules in various ways.
Oscillator: Also called VCO (Voltage Control Oscillator). Is what
creates a sound. It is a kind of sound based in geometric
waveforms like: Sine, Saw tooth, Square, Triangle, and even
Noise. These are very bright and brilliant sounds, and every one
of them has a specific kind of sound, that’s depending of the
number of partials contained. The characteristic of this Oscillator
is that it can change the pitch over time, can be modulated by
the LFO.
Filter: In a complex Synthesizer there are many filters. The most
useful is the Low Pass filter, because we need to remove the
unwanted frequencies. In general the oscillator is so bright that
we have to cut the excess highs. It also can be modulated, and
the parameter that can be apply the modulation is the filter cut
off. We can hear the sweeping sound across or the wha wha
sound, the sensation of the filter moving all the time. The Filter
also tends to be a resonator.

2. Amplifier: As known as VCA (Voltage Control Amplifier) Control
the volume of the sound and how it develops over time. It is
designed to move all the time. The principal modulator is the
Envelope that runs every time the key is pressed.
The synthesizer is not a static thing, it is changing over time. And
that change over time we called modulation. There are three
main modulators:
-The person itself manipulating knobs, fader, changing the sound
over time.
- The LFO and the Envelope.
LFO: It is an algorithmic modulator that creates cyclic variations
(up and down constantly) in any other parameters and can
control many things within the synthesizer like:
-The pitch in the oscillator, controlling the Vibrato.
It has wave shape like the oscillator (saw, square…), but the
difference is the rate. It is a Low frequency Oscillator, but lowers
than the range of human hearing (below 20 Hz).

3. Envelope: It is an algorithmic modulator that creates a kind of
shape that runs when a key is pressed. We find it controlling the
main amplifier, where we can make amplitude change over time,
giving for example a percussive shape or a sustained sound
shape. We can have envelopes controlling many things and
parameters: Pitch, filters. Etc.
It has four controls: Attack time – Decay time – Sustain Level –
Release time. Also known ADSR
Modifying those parameters we can get sound more percussive or
sustained or whatever needed.
When we have a modulation, there are three things to worry about:
Source, Destination and the Amount of the Modulation.
Thanks for reading. I hope you enjoy this short lesson as I did.