Doepfer A-196 PLL Tutorial Videos by Raul Pena

Raul Pena is back with a new A-100 tutorial series, this time all about the A-196 Phase Locked Loop (PLL) module.
- Its a slightly different type of series this time, Raul is asking for feedback and may do alternate versions.

A more detailed intro to the series and notes can be found HERE. 

Video 1: Doepfer A196 PLL Phase Locked Loop Basics

" Beginning of a series exploring the basics of the Doepfer A196 PLL Phase locked loop module. Video discusses understanding basic layout of the module and general layout. Audio demonstrations begin in next part of series "Experiments with the Doepfer A196 Phase Locked Loop-VCO and Comparator". Sound and Video by Raul Pena."

Video 2: Doepfer A196 PLL Experiments with the Phase Locked Loop- VCO and Phase Comparator Part One

" Beginning of a series exploring the Phase Locked Loop by Doepfer.Experiments with the Doepfer A196 PLL (Phase Locked Loop)- VCO and Phase Comparator. Part One of Two. For Basics on the Phase Locked Loop look for Doepfer A196 PLL Phase Locked Loop Basics. Sound and Video by Raul Pena."

Video 3: Doepfer A196 PLL- Experiments with the Phase Locked Loop-VCO and Phase Comparator Part Two

" Continuation of a series exploring the Phase Locked Loop by Doepfer.
Experiments with the Doepfer A196 PLL (Phase Locked Loop)- VCO and Phase Comparator. 

Part Two of Two. For Basics on the Phase Locked Loop look for Doepfer A196 PLL Phase Locked Loop Basics. Sound and Video by Raul Pena."

Oscillator Synchronizing

Interesting sound-effects can be obtained by the synchronising of (multiple) oscillators.
In a typical setup, one oscillator (master) restarts the cycle-period of the other one (slave) , what results in equal base frequencies on both oscillators. This is called Hard Sync.

The result is an irregular waveform with it's own harmonic spectrum, completely different from 'standard' waveforms

Soft Sync is a more general name for all kinds of oscillator synchronisation.
This form is very similar to Hard Sync, but here the slave oscillator is forced to reset to zero with every cycle of the master regardless of position or direction of the slave waveform, which often generates asymmetrical shapes.

In Soft Sync, rather than resetting to zero, the wave is inverted;  its direction is reversed.
Further variations to the sound can be made by comparing the sounds with different comparison tresholds. For more info see the Wikipedia page on Oscillator Synchronisation
Soft Sync sounds smoother  and distinctly different from hard-sync.
It is difficult to replicate this effect on digital synths, due to aliasing problems.

Soft Sync-like effects can also be created with other modules, for example a phaser or a Phase Locked Loop (PLL) Module.