Explain the usage of the 5 most important synthesis modules: Oscillator, Filter, Amplifier, Envelope, and LFO.

1. Hi, I’m Connal McIlwraith from Scotland.Hi, I’m Connal McIlwraith from Scotland.
The final assignment I have chosen is to:The final assignment I have chosen is to:
Explain the usage of the 5 most importantExplain the usage of the 5 most important
synthesis modules: Oscillator, Filter,synthesis modules: Oscillator, Filter,
Amplifier, Envelope, and LFO.Amplifier, Envelope, and LFO.
A synthesiser is a tool that allows the generation, modulation and amplification ofA synthesiser is a tool that allows the generation, modulation and amplification of
sound, generally for music.sound, generally for music.
Sound synthesis starts from simple waves. The sound is controlled bySound synthesis starts from simple waves. The sound is controlled by
connecting modules to each other. The general flow of a synthesiser is fromconnecting modules to each other. The general flow of a synthesiser is from
Oscillator (VCO) to Filter (VCF) to Amplifier (VCA).Oscillator (VCO) to Filter (VCF) to Amplifier (VCA).
The VCA is modulated by the Envelope and the LFO.The VCA is modulated by the Envelope and the LFO.
I will be explaining each in more detail.I will be explaining each in more detail.
Explain the usage of the 5 most important synthesis modules

2. Voltage Controlled Oscillator (VCO)Voltage Controlled Oscillator (VCO)
Function: The VCO creates the sound.Function: The VCO creates the sound.
The sound created is designed toThe sound created is designed to
change over time and starts from achange over time and starts from a
geometric wave form, the mostgeometric wave form, the most
common being from sine wave,common being from sine wave,
triangle, saw tooth, square.triangle, saw tooth, square.
It’s pitch or frequency is determinedIt’s pitch or frequency is determined
by, for example, a keyboard note.by, for example, a keyboard note.
Explain the usage of the 5 most important synthesis modules

3. Voltage Control Filter (VCF)Voltage Control Filter (VCF)
Function: Shapes the spectrumFunction: Shapes the spectrum
The VCF is designed to remove unwantedThe VCF is designed to remove unwanted
frequencies and there can be one or morefrequencies and there can be one or more
in operation at any one time.in operation at any one time.
There are several filter types:There are several filter types:
Low Pass Filter (LPF)Low Pass Filter (LPF)
High Pass Filter (HPFHigh Pass Filter (HPF
Band Pass FilterBand Pass Filter
Notch FilterNotch Filter
Comb FilterComb Filter
The LPF is the most common filter and is used to remove the harsh, bright highThe LPF is the most common filter and is used to remove the harsh, bright high
frequencies.frequencies.
The filter is defined by the following:The filter is defined by the following:
Cut-off frequency – the point at which the filter will workCut-off frequency – the point at which the filter will work
Resonance – emphasizes the cut-off frequency andResonance – emphasizes the cut-off frequency and reduces the feedbackreduces the feedback
Explain the usage of the 5 most important synthesis modules

4. Voltage Control Amplifier (VCA)Voltage Control Amplifier (VCA)
Function: Preamp that boosts theFunction: Preamp that boosts the
signal.signal.
The VCA shapes the overall volumeThe VCA shapes the overall volume
and how it develops over time and itand how it develops over time and it
is modulated by the envelope andis modulated by the envelope and
the LFOthe LFO
Explain the usage of the 5 most important synthesis modules

5. EnvelopeEnvelope
Function: Prescriptive path for the sound.Function: Prescriptive path for the sound.
The envelope normally controls the amplifierThe envelope normally controls the amplifier
but could control the pitch or the filter. In allbut could control the pitch or the filter. In all
cases, though, the envelope describes thecases, though, the envelope describes the
path according to the four parameters:path according to the four parameters:
Attack time – The time taken to reachAttack time – The time taken to reach
maximum volumemaximum volume
Decay time – The time taken to reach theDecay time – The time taken to reach the
sustain levelsustain level
Sustain level – The volume at which theSustain level – The volume at which the
sound will remain, while the key issound will remain, while the key is pressedpressed
Release time - The time taken to return toRelease time - The time taken to return to
zero after the note is releasedzero after the note is released
Explain the usage of the 5 most important synthesis modules
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6. Low Frequency Oscillator (LFO)Low Frequency Oscillator (LFO)
Function: control the sound in a cyclical wayFunction: control the sound in a cyclical way
The LFO generally operates in theThe LFO generally operates in the
range 0-20Hz, below human hearingrange 0-20Hz, below human hearing
and controls sweeping effect but canand controls sweeping effect but can
also create a vibrato effect byalso create a vibrato effect by
controlling the pitch.controlling the pitch.
Output of the LFO is normallyOutput of the LFO is normally
connected to the input of the VCO but it could control the filter, amplifier orconnected to the input of the VCO but it could control the filter, amplifier or
other.other.
The LFO is defined by changing:The LFO is defined by changing:
Shape - typeShape - type
Rate - speedRate - speed
Depth – amplitudeDepth – amplitude
Explain the usage of the 5 most important synthesis modules

7. The infinite combination of the five components goes to make a vast array ofThe infinite combination of the five components goes to make a vast array of
different sounds.different sounds.
I hope you enjoyed my presentation.I hope you enjoyed my presentation.
Thanks.Thanks.
Connal McIlwraithConnal McIlwraith
Explain the usage of the 5 most important synthesis modules