Music production is filled with a lot of exciting and awesome tools that you can use to really kick your track into high gear. Today we’re going to discuss LFOs, how to use them, and why you should be taking advantage of their wicked capabilities to add some ear candy to your beats.
What is an LFO?
A low frequency oscillator (LFO) is not low-end or bass. Low frequencies move very slowly compared to high frequencies, slow enough that we can actually hear the modulation with our ears.
The oscillator aspect of the LFO means that, at the speeds of a low frequency, it modulates whatever parameter we’re attaching to with an up and down, back and forth continuous motion at low-frequency speeds. Think of the rotating fan you might use during the summer that moves from right to left. That’s oscillation, and it’s exactly what we’ll be doing to the assigned parameter.
Why Use an LFO?
So why would we oscillate anything in our track? For one, it creates a sense of movement and interest within the instrumentation. Stale tracks get boring, fast. LFOs are a great way to breathe a little bit of life into your song–you can make a track pop with even a subtle amount of oscillation.
Also, LFOs are how we create exciting and unique sounds. Dubstep started placing an LFO on a low-pass filter, creating that sweeping, “wub-wub-wub” sound. We have killer sample packs like the Jameston Thieves collection that you can use now instead, but you can easily replicate the original dubstep utilizing this technique.
We can create a large amount of motion for dramatic, unique noises or modest amounts of motion for a shimmery texture on otherwise boring instruments. Combined with some exciting samples like our pack of samples from GRAVEDGR, you can really make something that slaps.
How to Use an LFO?
There are several ways to use an LFO, and the actual way to go about using them depends on what tool or synth you’re using. Some DAWs will allow you to create automation clips that replicate an LFO. Synthesizers will more than likely have one–or even three–LFOs built into their UI for you to assign and control.
LFO’s typically come with three controllable parameters:
-Rate: This refers to how fast the oscillator wobbles from its lowest value to its highest. If you were making your own dubstep line, you would want to automate this value to control the number of wobbles per bar to keep it fresh. Typically you might attach the rate of the LFO to the tempo of your session.
-Amount: Amount could have a few names in the UI, such as strength or value. This parameter reflects the dynamic range between the bottom of the oscillator and the top. Imagine that you had an LFO on the volume of a synthesizer, and when you turned it on, it would sweep from the synth being completely audible to silence. This would be the full amount or strength of the LFO. To adjust that a to subtler tremolo, you would turn the amount down until it was just right.
-Mix: The mix is the wet/dry ratio, and while not all synthesizers have this feature, it can be extremely useful when creating interesting sounds. This is the balance between the original sound and the version of the sound being affected by the LFO. If you placed the LFO onto the pitch of an instrument and tuned it to be subtle, you could play with the mix so that the original sound and warbled version would collide with each other creating a pretty excellent chorus effect.
What to Use an LFO on?
What you can use an LFO on really is only limited to your imagination and your system parameters. Synthesizers like Massive allow you to attach an LFO to just about any one of its dozens of knobs.
LFOs are a tremendous tool to help you get new and exciting sounds in your tracks, and we’ve put together a shortlist of ideas to get you started but remember to try your own ideas out and make something crazy.
As we mentioned, pitch is one of the many parameters you can attach an LFO to. Some plugins do this in the guise of being a vinyl or tape effect. By adding a subtle amount of warping to the pitch of an instrument or your entire track, you can emulate the sound of a spinning, old record.
You could take it a step up and create a natural-sounding vibrato with any instrument you like. By modulating the pitch a little more than subtle, but not too much, and turning up the rate to a bit, preferably to match the song’s tempo, you can add a human-like quality to your tracks.
Adding an LFO to the pan position of a channel can make some really cooling things. Playing with the stereo field isn’t particularly common, especially in music today. But that’s what makes it an interesting and unique sound that you can bring to your mix. Having instruments literally dancing around the user’s head while listening can be just the right amount of ear candy your song has been looking for.
LFOs on low-pass filters gave us an entire genre of music, so who knows what else it has in store. You can put an LFO on any type of filter to make it more interesting, and modulating the rate will allow you to create new and unexpected rhythms.
Synthesizers will generally have their own modulators that you can assign LFOs to, and the sky is the limit for musical creativity. Synthesizers can definitely be a bit intimidating because of their large number of buttons and dials, so it’s always helpful to do some research and watch tutorials. And if you just want some ideas to get you started, we have several sample packs full of awesome synth lines to spark some ideas.
Tips and Tricks
LFOs are exciting production tools, but they can be a little tricky to wrangle just the way you want them. Here are some tips and tricks to try out.
While you can automate any component of an LFO, automating the oscillator’s rate can give you some really sick noises. As we mentioned, you can come up with crazy rhythms with filters or even develop your own risers by automating the volume of an instrument. Start it slow and crank up the tempo until it’s a wild noise just before a drop.
Experiment with Waveform Shapes
LFOs are generally in the form of a sine wave, but they don’t have to be. Depending on the tools you’re working with, try out different shapes that are available. Triangle, square, curves, and stairs are all excellent shapes that get you different sounds. It might take a little experimenting, but that’s what makes production exciting.
LFOs are awesome tools for making new and exciting beats. Whether you assign one to the pitch or volume of your instrument, you’re bound to come up with something more interesting than when you started. You could put one on the wet/dry mix of a reverb or the time-step of a delay unit.
“New” doesn’t always mean “good.” Do some experimentation and mess around–get your hands dirty and come up with wild sounds. According to many major artists, some of the greatest and most iconic sounds in music were developed by accident after trying out a weird new technique.