Danilo Ferreira da Silva
3 December 2013
‘Beginners Guide to Synthesis’
the relationship between acoustic theory and the fundamentals of synthesis.
The Word Synthesis means combining different element and thats exactly what a synthesiser does combine different elements like pitch, texture, shapes of sound and you modify it create the sound you want. It sound simple but there are a few things you need to understand about sound for you to get the exact sound you need. and here are a few things were going to cover:
Pitch
One of the most used aspect of human expression Is pitch but what is pitch, and how does it work? well pitch is the rate of frequency that travels through the air while vibrating meaning, that if you want the sound to travel low you need the vibration thats coming from the source to travel slow making a low frequency sound which makes a low pitch sound and to get the sound to travel in high pitch you increase the rate of vibration and the will make a high pitch sound, pitch is vital in music and it was developed to work in synthesisers the same way as a piano.
Frequency
When thinking about frequency think of the tube and how the trans engine sounds,when you are at the station and the engine is on the train vibrates the everything around you and when the train moves you hear the pitch of the engine going higher and higher until the engine reach its beak and thats how frequency work you have your waveform + Amplitude + frequency which is how fast the waveform moves = sound.
Waveforms
To understand how synthesis works you need to understand how sound works. Sound though not seen works with physical energy, it is created by moving particles in the air which is described as sound pressure which is interpreted by the human ears and translated by the brain. If sound was to be seen by the naked eye, we would be able to see lots and lots of waveforms. Waveforms are basically how sounds behave.Sound is affected by many factors and lots of different textured surface this always and synthesisers capture a lot of that.
Waveforms:
Sine - The type of sound you get from hearing a Sine wave is a really specific single frequency type sound which sounds very useful when creating a baseline or a lead it is also the purest of sound you can hear when heard at a low frequency the sound is very pleasant but when you hear the sound at a high frequency its unbearable you might argue that the sound you hear when you have tinnitus is a sine wave because of the luck of texture.
here is also a link which represents the sound of a sine wave
Square - the square has more layers of frequencies which makes the sound sound more dirtier you might even confuse the sound of a square and a triangle waveform.
here is a link which represents a square wave
Triangle - A triangle sound is great to use to make brass sounds it is also a easy way to get distortion due to the large amount of frequency level trying to fight each other.
Sawtooth - sawtooth just by the name makes explain a lot the sound the sawtooth produces is very arising and hard to hear a long period of time but you can get lots of different texture when mixing the sawtooth with different waveforms
Sawtooth -
The only realistic sounds we hear as humans from natural sound pressure is the Sine wave, the square,triangle and sawtooth waveforms are only due able within synthesisers, it might sound a bit complicated and a bit irrelevant but when it comes to creating sound it is vital.
Now that I explained the basics, i will explain in detail how you could manipulate, edit and create your own sound using different synthesis and what type of synthesis you could use to make your sound.
ADRS Envelope
An ADRS Envelope is a Tool vital when creating your own sound and most sythersisers will have a built in ADRS Envelope built in. The way they work is simple you have Attack which is how fast the sound reach its people when the sound is played a short attack means you can have a smooth sound with out any bang to the sound.Decay mean how long or short you want the peak to meat fading of your sound.A sustain means how long the sound stays at the frequency when holding the keys down.release is how fast the sustain level reaches zero.
another aspect I want to speak upon is is Filters and how you can use it to manipulate sound.the are 3 main type of filter Low pass, low pass filter all frequencies above and every extra noise above gets cut off straight a way. High pass, high pass works the same way as the Lowpass but it cuts of the low end instead. Band pass allow only the sound around the chose cut off point to get throw.
LFO
Low - Frequency Oscillator is a Digital signal that moves on really low frequencies it is used to create rhythmic grove as-well. Although they effect sound they do not change how it sounds they only manipulate an already made sound by pulsing. you can sync the sound to different groves 1/4, 2bars or choose a wave shape to trigger the sound at.