Arturia cs-80v Manual De Usuario

 

54

6.1.2  The filter or VCF 
 

The audio signal generated by an oscillator (the waveform) is next generally directed to a 
filter module (Voltage Controlled Filter).  It  is  this  module  that  we  use  to  model  the 

sound by filtering (by subtraction, which explains the name given to this type of 
synthesis) the harmonics situated around a cut-off frequency. It can be considered like a 

sophisticated equalizer that reduces, depending on the case, the high or low frequencies 
of a sound. 

 
The removal of undesirable frequencies, with a cut-off frequency is not done suddenly 
but progressively, this, depending on the filtering slope. This filtering slope is expressed 

in decibels per octave (or dB/Oct). The filters used in classic analog synthesizers have 24 
dB/Oct or 12 dB/Oct slopes. 

 
 

The CS-80V offers 2 types of slope (where the CS-80 had only the 12 dB/Oct slope). 
 

 

 

 

 
On the CS-80V, you have access to 3 different types of filtering. Let’s have a look at 
some of their properties: 

 

 

The  low-pass  (LPF) deletes high frequencies going from a frequency limit (the 

famous cut-off frequency) and only lets low frequencies through. Depending on the 
setting we will here the sound becoming more or less «brilliant», more or less 

«dampened».  

 

This is the type of filtering that you will find more often than not on synthesizers that use 
subtractive synthesis. It can be found on most of the recent analog and digital 
synthesizers. 

 

 

 

 

 
•  The  high-pass  (HPF), unlike the low-pass, eliminates low frequencies and only lets 

high frequencies through. The sound will become «finer». It is very useful for 
removing redundant low frequencies with a bass sound for example.