How to do Pulse-Width Modulation (PWM) in Sylenth1

Sylenth1 is a pretty simple but powerful synth. But it’s simplicity often has people thinking that it’s not capable of certain things. I read in some forums for example that in Sylenth1 it’s not possible to modulate the pulse-width of a pulse wave and that you can only use the three different pulse waves sylenth provides. While it is true that Sylenth1 does’t have a simply integrated PWM feature it is still very possible to set it up, if you know your way around Sylenth1.

The basic approach goes as follows:

You set up two sawtooth waves in two different oscillators invert one of them (which if you think visually flips it up side down) and then modulate the phase of one of the oscillators. In Sylenth1 you can only modulate the phase of Part A compared to Part B and not for example the phase of oscillator A1 to oscillators A2. that means if you wanna use an LFO or envelope to modulate the Pulsewidth you will have to use oscillators from different Parts, for example oscillators A1 and B1 or A2 and B2 or A1 and B2. You get what I mean 😉

This simple set up already enables you to create a pulse wave of any pulse-width and also allows you to do pulse width modulation. But it might be a bit tough to wrap your head around how this works behind the scenes. In order to explain this technique in detail I recorded a little video going into detail about how PWM works in sylenth1:

In case your interested why I want through the fuss of finding a way to set up PWM in sylenth1:

I was checking out how to make some of these very sweet sounding classics house pads and basses and other sounds in that direction. I realised that many of them were created with old-school synths like the roland juno-60 which was dominating the scene back in the days but is still used a lot today. Even by guys like disclosure for example. I checked out what kind of features these old skool synths have and realised that they all in someway or other have a PWM feature. Since I like to work with sylenth1 I really wanted to find a way to set it in a way that resembles the set up of a juno or other old school synth. coming of with a way to do PWM was the first step in that direction 🙂

Hope it was helpful