Introduction to Computer Music: Volume One

4. Common analog patches

The following diagrams shows several common patches used with modular analog synthesizers. Many current software synthesizers, such as Absynth have adopted the same signal flow. The legend at the bottom indicates the marking used for the audio signal path, the control signal path(s) and gates. A gate is nothing more than a pulse. A gate from a keyboard begins when a key is depressed and ends when a key is released and lets the envelop know when it is time to start it attack phase (key down) and begin its release phase (key up). The diagrams use consistent symbols for the different modules (circle=oscillator, square=filter, triangle=amplifier).

S=audio signal path
VCO=voltage-controlled oscillator
C=control voltage path
VCF=voltage-controlled filter
VCA=voltage-controlled amplifier