Most Common Module Settings

Explain the usage of the 5 most important synthesis modules

Oscillator, Filter, Amplifier, Envelope and LFO

coursera.org

Most Important Synthesis Modules

Oscillator : It’s a voltage controlled oscillator and creates the sound using geometric forms (VCO)

Filter : It’s a voltage controlled filter and shapes the spectrum (VCF)

Amplifier : It’s a voltage controlled amplifier that shapes the volume (VCA)

Envelope : It’s a modulator attached to the VCA that changes the shape

LFO : It’s a low frequency oscillator that modulates the voltage controlled oscillator

VCO, LFO Low Pass High Pass Band Pass Notch, Comb

Envelop

L E S S O N 6 A S S I G N M E N T

Hi fellow reader I am John Soulakellis from Greece Athens. This presentation is for the course of Introduction to Music Production from coursera.org

I will cover the topic of Explain the usage of the 5 most important synthesis modules

Thank you, for having the time to read my

assignment

VCF Sine, Sawtooth Triangle Square, Pulse Noise, Random

Attack Decay Sustain Release

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MOST IMPORTANT SYNTHESIS MODULES WEEK 6 ASSIGNMENT

Synthesizer

Oscillator (VCO) )

In most synthesizers like the online one below from http://www.angryoctopus.co.nz we can see the important modules that I will talk about.

Is the sound creator and always outputs sound that is generated based on geometric forms. These wave shapes can be Sine, Square, Triangle and Sawtooth.

Sine wave is a single tone with no harmonics, a smooth and pure sound.

Square wave has only odd harmonics and also has instantaneous transitions between high and low levels.

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MOST IMPORTANT SYNTHESIS MODULES WEEK 6 ASSIGNMENT

Triangle wave adds odd harmonics to the sine wave and has linear rise and drop from lowest and highest values.

Sawtooth adds even harmonics to the square wave and there is a linear rise to the highest value then an instant drop to the lowest level.

Good starting point for creating sounds is to use square or sawtooth because they are rich in harmonics. Because of this, you may end up with brighter sounds that amplifies specific frequencies that you want to avoid and you will have to use a filter after these waves to make them sound smoother. If you want to make really interesting sounds you have to use two or more oscillators in parallel.

Waveforms and when to use )

Sine : Pure mellow sound like Flute

Triangle : Mellow sound with some harmonics

Saw : Buzzy sound with many harmonics, sounds like Brass horn or String

Ramp : Inverted Saw, sounds the same but useful for modulation

Pulse : (Square) Hollow sound, many harmonics, width can be controlled, sounds like

Woodwind or Clarinet

Filters (VCF) As we said before if we have a harsh – bright sound from the VCO we have to use a filter to make it sound smooth. Removing unwanted frequencies does this. The most important type of filter is the low frequency pass that removes the high end. We can use them modulated like oscillator and because of this, filters are changing the feedback on a delay line and this creates bigger peaks, so we may end up with a too bright or too dull sound. As we sweep the cutoff frequency knob we can hear the resonant peaks of each harmonic. To remove the problem we have to change the cutoff frequency or use envelopes to change after output. A thing to be aware of is that filters in a synthesizer tend to be resonant filters and we have major boost in the sound. If we want to remove frequencies we don’t use resonance but if we want to amplify harmonics we have to.

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MOST IMPORTANT SYNTHESIS MODULES WEEK 6 ASSIGNMENT

Amplifiers (VCA) In some synths is just pan volume knob in others is embedded with the envelope modulator. If it is just a pan volume the only work is to adjust the volume.

Envelope Is a modulator attached to the VCA and is designed to move all the time every time a key is pressed. In fact is a predefined path using the ADSR controls.

Attack Time (A) : is the time it takes to get from 0% to full value when you press a key. The bigger the attack time the slower to come off the ramp. Decay Time (D) : is the time it takes to get from full value to sustained level if it is set. Sustain Level (S) : is the level that the note stays while it’s being held. Release Time (R) : is the time it takes to get from sustained level down to 0%. If we want to emulate a violin we have a strong attack, then to settle to a sustain level. The same settings will apply to a blowing organ like trumpet. Initial burst of air and settle down to sustain level. Real instruments that are blown or bode will have a sustaining envelope. If we want a percussive sound that is plucked or hit we have to set sustain to 0% and we have to use decay to control the length of the note. If we add also a little release time and set it close to the decay time we achieve a piano like sound. If we want a punchier sound, we have to decrease the decay time. If we want to fade out quicker, we have to reduce the release time.

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MOST IMPORTANT SYNTHESIS MODULES WEEK 6 ASSIGNMENT

LFO Is actually an oscillator that is designed to work to low frequencies from 0Hz – 20Hz. It is also a modulator and will modulate the VCO that works from 20Hz - 20KHz. We only need to worry for

i) LFO source ii) VCO destination iii) the amount of modulation.

LFO can also has wave shapes like VCO and because of the frequency range they are used, we can’t hear directly the output of the LFO but, has huge impact on the output of the VCO that we hear. LFO’s are general purpose devices that can be used to modulate a variety of things but the most common use is for vibrato effect and we set it around 3Hz – 6Hz. This cyclic variation can also be used for controlling the amplitude of the VCA or changing the pitch of the LFO. So the result in not something we hear directly, but we hear its impact on the oscillator frequency.

Multi-uses We can have an LFO controlling many things. We can have an LFO controlling a filter, another one controlling an amplifier and another one frequency. We can have an Envelope controlling pitch, another one controlling a filter, another one frequency. We can have more and more Envelopes and more and more LFOs. It depends on what we want to do as we create the sound.

Summary • All modulation requires a modulation source, a destination and an

amount • LFO is controlling the pitch of the oscillator • Envelope is controlling the main amplifier and give a sustaining or

percussive shape • We can have more than one VCOs • We can have more than one LFOs, LFOs controlling other LFOs • We can have more than one Envelopes

What I learned from this week’s assignment was more technical terms, better understanding of how synthesis works, module types, how to create sounds, a better way of using a DAW, what to check before recording, what to change, how to set it up and finally how to record it.

Thank you for your time!

MOST IMPORTANT SYNTHESIS MODULES

WEEK 6 ASSIGNMENT

PICTURES LINKS http://www.angryoctopus.co.nz

http://www.synthesizers.com/q106.html

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