What exactly are LFO shapes and why do you need to know how to use a sine wave, triangle wave and pulse wave? Here’s the answer…
The LFO shape function is an essential part of a (subtractive) synthesizer that you can usually find in the LFO area.
What are LFOs?
An LFO stands for Low Frequency Oscillator and, just as an envelope, it can create a movement with your sound. Whereas an envelope will produce a single or one-time motion, an LFO can produce a repeating motion. This way, an LFO can modulate or vibrate your sound based on a wave pattern.
The modulation can take many forms, depending on your design. Thereby, you can create different types, such as a volume modulation, panning modulation, pitch modulation or filter modulations. But also, you can choose when the modulation should happen, how fast the modulation should be, and which shape the modulation should have.
So, for example; if you’d select a pitch LFO, you can move the tone of your sound up and down repeatedly at a certain rate. In the same way, if you’d select a panning LFO, you can move the sound between the left and right speaker sequentially at a certain speed. This way, you can set your sound in motion very flexibly, depending on the effect you wish to produce. Thus, it’s very important to understand all the settings on the LFO area, such as the LFO shape.
How to use LFO shapes
The LFO shape defines the behavior of the modulation. It determines how the modulation moves so to speak. Therefore, it uses a waveform, like a sine, triangle or pulse. And by selecting one of these waveforms, you determine upfront which modulation sequence you wish to create.
Often, you will find many different waveforms to choose from, but the most common ones are the sine, triangle or pulse. But how does each of these affect your sound?
- The sine waveform moves in a gradual non-linear way. It makes the modulation sound wobbly with smooth transitions.
- The triangle waveform moves in a tight linear way. It makes the modulation sound quite like a sine, but less wobbly and with straighter transitions.
- In contrary, the pulse waveform moves in an abrupt or immediate way. It makes the modulation sound bipolar. So, it switches from one state to the other without any transitions.
The LFO shapes set the initial conditions
So, each shape has a different impact on how your sound modulates. Mind you, selecting the shape is part of the initial conditions. So for now, the LFO doesn’t affect the sound as of yet. However, this will change quickly when you start to use the LFO amount, which we will explore next in the complete “Synthesizer for beginners” series.
Synthesizer for beginners
The “Synthesizer for Beginners” series is a huge collection of quick lessons about sound design and synthesis. Each lesson explains one part of how a subtractive synthesizer works, which is vital to know if you’re an electronic music producer.
Most people have the attention span of a butterfly and therefore miss all the important tips later in my videos and posts. Still, I don’t want you to miss a thing and that’s why you will see these short clips on Screech House. Each short clip explains a bite-sized topic from one of my longer videos. This gives everyone the chance to focus solely on what they need and thereby also saving a lot of time.
Today’s short clip is from the 4-part “Synthesizer Explained” video course. Watch the full episodes here:
The “Synthesizer Explained” video course is now finally available as an exclusive guide. This easy-to-read book is jam-packed with valuable info about the essential basics of sounds design, including practical tips and bonus cheat sheets.
Since the day of release, many people have already read it. But if you haven’t, click this link to get your copy: Synthesizer Explained.
Make sure to get it now, else you risk being too late and miss out.