Today, you will get all the essential basics you need to know exactly how to use an LFO on your synthesizer.
Sound design basics part 4: LFOs
This is the final part in a 4-part series where you will learn the absolute essential basics of sound design. In today’s post, you will discover how to use LFOs. In the remaining parts of this series, you will find out how to use oscillators, how to use filters and how to use envelopes.
Why you need to know how to use LFOs
When I was just starting out as a producer, I had absolutely no idea how a synthesizer worked and what all these weird knobs did. Quite frankly, I was downright ignorant, and this really hurt the quality of my songs.
That’s why; to spare you these experiences, I’ve created this short-course series where you will learn all the essential basics of sound design, which for today is: how to use LFOs.
Of course, a brief video cannot go into full depth, so to benefit from way more details and a complete step-by-step approach, just get the Sound Design for Beginners guide. This well-received guide will teach you everything you need to know as a beginner, including oscillators, filters, envelopes, LFOs and bonus content. Just click the link and you can start right away.
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. Thereby, each movement always follows a certain waveshape pattern, such as a sine wave, triangle wave or pulse wave. So, the shape dictates the way the modulation occurs.
LFOs step by step
Well, hopefully that doesn’t sound too complex, but I promise you, it’s really easy. That’s why; keep reading until the very end, as we will cover the LFO step by step and I will give you practical examples, so you will get this in no time.
Free sample pack
Also, if you haven’t yet, you can download my free sample pack by clicking this link. It contains many high-quality EDM samples that you can use immediately.
Use you own favorite synthesizer
And finally, as for demonstration purposes throughout this tutorial, I am going to use the Sylenth1 synthesizer. However, you can use your own favorite synth, because many of them kind of work in a similar way. Now, let’s explore the first LFO setting which is the target.
How to use LFO target
An LFO target, also called destination, defines the sound modulation. It dictates which knob has to move. So, by setting the target you choose upfront which type of modulation you wish to create. There are usually many targets to choose from, but the most common ones are volume, panning, pitch, filter cutoff and filter resonance.
If you don’t know what this means, again, start with the Sound Design for Beginners guide first.
So, if you want to create a volume modulation, select volume as the target. If you want to have a pitch modulation, select pitch as the target. And so forth.
Be aware though that selecting a target on itself doesn’t produce an effect. In order to do that we have to use the other LFO options as well. So, stick around as you don’t want to miss these.
How to use LFO shape
Next in line is the LFO shape. The 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?
Sine wave
The sine waveform moves in a gradual non-linear way. It makes the modulation sound wobbly with smooth transitions.
Triangle wave
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.
Pulse wave
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.
So, each shape has a different impact on how your sound modulates. And watch the video to learn how to select one of the available waveshapes on the Sylenth1.
Again, we’re still setting the initial conditions here. So for now, the LFO doesn’t affect the sound as of yet. However, if you stay with me, this is about to change quickly.
How to use LFO amount
The LFO amount, sometimes called gain, controls the intensity of the sound modulation. It dictates how extreme the modulation occurs. This way, a higher amount results in a stronger modulation and a lower amount results in a weaker modulation. So, the more you open this knob, the higher the intensity.
Two directions: left & right
Though, usually you will find the LFO amount knob going in two directions, whereby the center represents a zero value, which means no modulation. By choosing between left or right, you dictate in which way the modulation occurs. This way, the behavior of the LFO will completely invert if you move the parameter to the opposite side. So, the orientation of the LFO amount sets the direction for the movement.
Example: pitch LFO
If you lost me hear, don’t worry. Let me just give you an example. Let’s say you want to make a pitch modulation. Therefore, you select “pitch” as the target and you open the LFO amount to the right. Great, the tone of your sound first goes up and then goes down repeatedly.
However, instead of choosing right, you now orientate the LFO amount to the left. Suddenly, the tone of your sound first moves down and then moves up repeatedly. So, the modulation has been inverted.
And let me show you that right away in the video above. But be aware that the Sylenth1 has two different amount settings. One to define the direction and amount for the target, and one for the general amount of the LFO. So, we need to tweak both to produce a result.
As you could see, this is starting to go somewhere. But now, let’s speed things up.
How to use LFO speed
One of the characteristics of an LFO is the ability to set the speed for the modulation. The LFO speed, sometimes called rate, determines how quickly your sound modulates. So, a higher speed produces a rapid vibration and a lower speed generates a slower vibration.
This is very straightforward and doesn’t need much explanation. So, let me just show it to you in the video.
Tonal side effect
Mind you though, as I also talk about in the Sound Design for Beginners guide, higher speeds can produce a tonal side-effect. After all, LFOs are oscillators as well. Their rates dictate which lower frequency will be added to your sound.
However, this is mostly a nonissue and only noticeable at higher speeds and higher amounts. So, let’s move on and stay with me for one more minute as we go to the last options for today.
How to use LFO delay & attack
Some synthesizers allow you to set a delay and attack for the LFO. The delay and attack deal with the starting time of the modulation. They control when and how quickly the modulation begins.
Other synthesizers may give you even more control over the timing of the modulation, such as the full attack, decay, sustain and release times. If you want to learn more about these, please check out the envelope tutorial as it’s all in there.
No attack or delay settings? Use this advanced trick…
Unfortunately, many synthesizers, such as the Sylenth1, don’t have direct timing functions for the LFO. So, I cannot show it to you. However, you could assign the LFO to an envelope and have full control over the timing that way. Nonetheless, this is slightly more advanced, and I don’t want to intimidate you in this beginner series.
But don’t sweat it. This is more than enough to know when it comes down to LFOs. It should already give you all the tools needed to produce epic sound movements.
Beyond LFOs: sound design for beginners
That should do it for this one, but if you’d like to explore all the synthesizer settings in full depth and at your own pace, just get the Sound Design for Beginners guide. Many people have already read it, but if you don’t, start now by clicking the link and I’ll see you there.