donderdag 29 augustus 2013

Synthesizer Terminology

What is a synthesizer?

A synthesizer, also known as a synth, is an virtual or digital instrument which can form sound with several different methods. It can be played trough a built-in/midi keyboard, or trough a sequencer or arpeggiator. These sounds can then be further modified by changing the parameters that are included in the synth.

So, what's commonly seen in a synth?

Oscillator (Also seen as OSC)

The very foundation of any synth. A oscillator is a waveform generator which loops the wave at such a speed, that a sound is made. The quicker the loop, the higher the pitch (tone). The speed of the loop is called the "frequency". So, higher frequency, is a higher tone.

     Basic waveform types:

           Sine wave - A "smooth" sound, so to say. Gives a clean sound.

           Square wave - The name says it like it is, this wave is built out of square blocks. The square wave gives a very full sound, I find these great for leads.

           Triangle wave - Actually a sinewave, sharpened. Still quite a clean sound, but with a bit more texture to it.

           Saw wave - The roughest in the list of basic waveforms - has a piercing high end sound, that can be filtered out.

These are the basic waveforms that can be used and in turn combined, to create entirely new waveforms, which can even create known sounds that usually are heard in real life instruments, like strings, trumpets, and piano's,

More information about oscillators can be found in the "Oscillator Terminology" section.


Another essential part of a synth, is the filter.
A simple concept, but (I found) hard to grasp fully. 
In short, a filter "filters" a certain frequency range by eighter passing or rejecting tones above or under the filter frequency. There are usually three parameters linked to the filter:

           Filter Frequency
     Also known as the cutoff point in a filter, this is the point where the filter will eighter cut or pass the tones above or below the cutoff point. How do you know what filter does what, when? 
This seemed daunting to me at first, but it's quite easy to understand once you see it explained, and use it a few timeIn the end, it's just understanding English, but still requires some thought at first.
          High-Pass filter - Passes the high pitched tones. Can be used on hi-hats for example. Also known as a low-cut or low-reject filter.
A high-pass or low-cut filter, with a cutoff frequency of about 78 hZ.

          Band-Pass filter - Passes the tones in-between the high's and low's. Think snares, claps.
          Low-Pass filter - Also known as a high-reject or high-cut filter. Does exactly the opposite of a high-pass filter.
A low-pass or high-cut filter, with a cutoff point around 2500 hZ.

   There are some more commonly used filter types, such as the
          Notch-filter - which actually cut's a very small frequency range. 
     and the
          Peak-filter - the opposite of the notch, this boosts a very small frequency range.


    A common knob seen on filters is the "Resonance" or "Res" knob. The only thing this really does, is boost the sound at the cutoff point. This is easier shown than explained, so here:
The small peak a the cutoff point is commonly known as the "Resonance"
At a cutoff point of 25kHz, you see the resonance brings up the sound at just around that point.

For more information regarding filters, go to the "Filter Terminology" section.

Low Frequency Oscillator

More often seen as an "LFO", a low frequency oscillator  is exactly what it says it is.
It's an oscillator, in whatever kind of shape you want (or is available in the synth, to be more precise)
9 out of 10 times, the LFO itself will not be making any sound.
Unless you turn the frequency up very high, it's highly unlikely the LFO would even make ANY sound when routed (routing = connecting, wireing) towards your speakers. And doing this kind of means turning it into a regular oscillator, in which case you could just as well use a regular oscillator.

So why do we have LFO's?
To edit the parameters we see in the oscillator and filter sections, of course!
A quick example would be to rout the LFO to the Filter Frequency of your synth.
Turn up the LFO rate (the speed of which it oscillates) to about 1/8'ths, turn up the resonance of your filter slightly, and you should hear the now-commonly-heard sound of a basic wobbble.

Another basic technique would be to route the LFO to the oscillator pitch, giving it a bit of tremolo in the sound.
Maybe rout it to the pan (left/right output) of the instrument, making it sound like the source of the instrument is moving from left to right. That's not all though, you could practically apply an LFO to nearly any parameter in your DAW, like changing the amount of a distortion effect up and down in a wave.

More on LFO's in the "Basic Techniques" section.


If an oscillator is a sound source, and an LFO would be a modifier, we could place envelopes in the same range as an LFO. Like an LFO an envelope can modify anything in your sound.

Better yet, an envelope is almost always used in a synth, if only for the amplitude (the "loudness" of the sound.)

An important thing to comprehend with envelopes is the ASDR model used.
When connected to your amp envelope, ASDR would stand for:
Attack - The time it takes for the sound to reach top volume
Decay - The time it takes after the attack, to move to the sustain level
Sustain - The volume level the sound stays at untill the key is released
Release - The time AFTER the key is released for the volume to drop to zero.


An Arpeggiator (sometimes seen as ARP) is a function available on some synthesizers which will actually simply play certain notes on a certain rate.

Simply said, it just turns on the note for a set amount of time, on a set pitch, and then move on to then next "Step" in the arpeggiator.

This could be 16 quick notes in the same pitch, or 10 notes with some shuffle and pitched up and down.
Some arpeggiators even go further than the gating (note on) and the pitching, and allow modification of any parameter in the synth.
For example, every step would turn the frequency knob up or down.

This way you can get complex patterns and soundscapes.

The Arpegiator attached to the Thor synthesizer by Propellerhads. The step sequencer is seen to the right.


All a shaper actually does (this, together with alot of FX like distortion and overdrive) is change the waveform by eighter cutting the top and the bottom. Note this is one way of waveshaping, I might add more later.

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