Serum – the trusty companion of so many music producers. There’s really not much it can’t do, but like any instrument, it requires practice and creativity.
It can be extremely daunting to open up a fresh patch in Serum, stare at the blank slate in front of you, and try to get from the default saw wave to a head-crushing bass sound, or a gentle bell pad.
This list is to give you a few places to start your sound design process, and to set you up with some common techniques you can keep in your back pocket, which you could probably use in other synth plugins too!
This list will start out with easy techniques, and progress to more advanced ones, so as to be friendly to all levels of music producers. Easier ones will have * next to them, and the hardest will have ***.
Filter your sounds *
The filter in serum is one of the most ubiquitous components of the whole synth. It can take the edge off of harsh sounds, or it can create floaty atmospheres by removing the low end, but that’s not the end; not even close.
There are 96 different filter types, organized into four categories, that you can try out and play with, ranging from your standard low pass and high pass filters to ring mods, formant filters, and reverb filters.
The cutoff, resonance, drive, and pan knobs are pretty self-explanatory if you’re familiar with filters already, but for those new to it, here’s a breakdown of all the functions on the filter:
- Cutoff: sets the frequency threshold for the filter to affect. For a high pass filter, setting the cutoff at 100 Hz will allow all sounds above 100 Hz to be unaffected, and will cut off all frequencies below 100 Hz.
- Resonance: creates a notch around the frequency of the cutoff, boosting them in a narrow band. The result is an emphasis on the cutoff frequency any time it moves. This can also create vowel sounds.
- Drive: introduces an analog-like distortion to the filter, and typically makes it louder while adding harmonics.
- Pan: affects the left/right channels differently. Moving the pan knob to the left will raise the cutoff frequency on the left side, while lowering it on the right, creating a more defined stereo image.
- Fat: this knob can change in function, though by default it is a Fat knob. This just makes things… fatter! It can also become a second cutoff filter for the multi-filter modes, among other things.
- Mix/Level: you can mix the filtered signal with the unfiltered, or by clicking the name, you can change it to a Level knob, which becomes essentially a volume knob.
One common sound you can make with just the filter is a pluck sound. To start, click Envelope 2 and set the Decay to 250 ms and the Sustain to 0%.
Then, click and drag the ENV2 label and move it over to the filter Cutoff. You should see ENV2 hovering over it before you release, followed by a blue semicircle around the Cutoff parameter.
The Cutoff will now follow the envelope you created, and you can adjust the distance it travels by clicking and dragging the (very) small blue semicircle icon outside of the actual semicircle up and down, as shown in the picture.
Increase the Resonance to about 25% and try it out! You should have a saw pluck that’s good for 80s style basses, or quirky arps.
Play with wavetables and oscillators *
Serum provides a plethora of options to choose from with wavetables, which are also conveniently organized for you.
These wavetables can all have very different sounds and textures, which you can combine using both of Serum’s oscillators in tandem. The possibilities are truly endless.
For this, we’re going to make a pad that moves and evolves. The first thing to do is to pick a wavetable, and for this we’re going to use Evol Sweep, which is under Digital.
Our next step is to tweak LFO 1’s parameters. Start by clicking the box next to DOT so it turns blue, changing the rate to 3 bars, and setting the mode to Trigger.
The DOT box allows you do use in-between values for the rate, which normally only uses 4 bars, 2 bars, 1 bar, 1/2, 1/4, etc.
You could also uncheck BPM and set the rate in Hz, which would desynchronize it from the tempo of your song.
The Trigger function means that the LFO will start from the beginning every time a key is pressed.
Once that’s all done, click and drag the LFO 1 label over to the parameter WT POS on Oscillator A. This will move the wavetable position in accordance with the LFO.
Moving back up to Oscillator A, turn the number of voices up to 7, turn the Detune down to 0.13, and adjust the range of the WT POS modulation to be 0.55 (again, the blue semicircle).
Unison voicing is a powerful sound design tool that plays copies of the sound and slightly detunes them from each other, creating a huge stereo image as well as much more unique textures, and introducing motion into an otherwise static sound.
You can tweak the separation of the voices using the Detune knob, and we usually like to keep it around 0.12 so it doesn’t sound like it’s completely out of tune.
Lastly, let’s add one more parameter to our LFO. Click the OFF label just to the right of the WT POS, and you’ll see a dropdown menu of more ways to alter the wavetable, called the Warp mode.
Select Sync (Window Full), then click and drag LFO 1 to assign it to this knob. Adjust the range so that it plays opposite of the WT POS range, meaning when the wavetable position is going clockwise, Sync is going counter-clockwise, and set the range to 25.
Then move the knob itself (not the range) so that the end of the range is as far left as it can be, while still in the scope of the knob. Confusing? Take a look at this picture:
You should have a pad that sounds like shooting stars across the night sky (whatever that means). If you want to get spicy, try playing around with the warp options, and setting it to a different LFO with a new rate.
Making a simple riser **
Now that we’ve covered some basics, let’s get funky with it. Risers are very useful in electronic music to create tension before big moments, and transition between sections.
For this, we’re going to set Oscillator A up as a square wave, which you can do by choosing the Basic Shapes wavetable from the Analog section, and using WT POS to get it to the square wave.
We’ll increase the voices to 9, and set the detune to 0.05 this time. For the Warp parameter, set it to FM From B, and turn on Oscillator B.
Set Oscillator B’s wave shape to a sine wave (Basic Shapes has a sine wave too!), then set A’s FM start position to 15% as well.
Turn the level of Oscillator B all the way to zero, so it doesn’t make any sound, and it only controls the frequency modulation of Oscillator A.
Now let’s set up the LFOs. Click and drag the point on LFO 1 to be a ramp going up to the right, and set the mode to ENV. Change the rate to 2 bars, and this one should be all set.
For LFO 2, turn BPM and ANCH off, keep the mode in OFF, and put the rate somewhere around 2 Hz. We don’t need to mess with the shape of this one.
Finally, we will need an envelope, but we don’t want to use ENV 1 since by default that controls the global volume. All we need to do is set the Attack to about 4 seconds.
Time to assign! LFO 1 will control the course pitch of OSC A, which is up in the top right of oscillator A’s window, having 2 dashes as its default value.
It will also control the Detune amount, with the range being set as the remainder of the distance on the knob. Drag it on over to the FM From B as well, and give it 15% range.
Lastly, it will control the filter Cutoff, with the range being just enough that the filter is all the way open by the end of it, starting at about 500 Hz. Set the Resonance to about 50% too!
LFO 2 will control the Pan knob of OSC A, and the range should be the entire knob’s worth. That’s all!
In a bit of a twist, ENV 2 is going to be assigned to the rate of LFO 2, with a range of around 42. This means LFO 2 is going to increase in speed over the course of ENV 2’s attack time. You’ll hear the effect of this in the side-to-side panning of the riser, as it goes faster and faster.
Fun fact: this is the same idea behind the tremolo effect on Billie’s voice in Bad Guy by Billie Eilish.
And here’s the full picture!
This sound can be modified even further to suit your needs, and is fun to use with different wavetables, rates, mod parameters, and anything else you can think of!
Double FM growl bass **
The last sound touched on the concept of FM, but to summarize, one oscillator’s wave becomes the modulation source for another wave, in a relationship called frequency modulation.
The first wave is the modulator, and the second is the carrier. But what happens when you modulate a modulator? Let’s find out!
To set it up, turn on the Sub and both Oscillators A and B. Set the level of the Sub and Oscillator A to zero, and leave B’s where it is.
Then, use the same Basic Shapes sine wave table on both oscillators as well. Using the OCT/Octave function, click and drag the octave of the Sub to -1, OSC A to +4, and OSC B to +1. All told, it’ll look like this:
Now it’s time for the frequency modulation. Set the warp mode on OSC A to FM From Sub, and on OSC B to FM From A.
Now the Sub will be modulating Oscillator A, which is cool enough, but then that already-modulated signal is going to modulate oscillator B too!
Set the warp on OSC A to 40%, and on B to 44%, and see what happens. It may not sound impressive right now, but we’re going to keep going.
Put LFO 1 into a shape like the one below, set it to Trigger mode, and assign it to the filter Cutoff (make sure B is checked on the filter!) with 25 range, and set it to about 110 Hz.
Switch the filter type to High 12 and turn the resonance up to about 45%. Then, assign LFO 1 to OSC B’s FM warp, with a range of 6. Immediately more growly!
Now let’s dive into Serum’s FX section, which we haven’t even peeked at yet. Serum has a few simple, but really powerful effects, and a few are so prolific as to even have their own standalone versions that you can download for free to apply as plugins to other sounds!
We’re going to start by turning on the Compressor, and all we need to do it click the little box that says Multiband. Done!
Next up is the Distortion, which has tons of cool distortion types, but we’ll stick with the default Tube distortion for now. Crank it to about 90%, turn this mix down to 70%, and that one’s done too!
Last up, we have Hyper/Dimension, which is a very unique widener. Hyper does the same thing as unison voice detuning, but outside of an oscillator, while Dimension adds a single slap-back delay to create stereo width.
The default settings leave Dimension off, which is fine for now, since the results from Hyper are profound enough.
And now you’ve got a nasty, growling bass to fit in with any dubstep drop!
The hypergrowl ***
Ok, so we didn’t come up with this technique, but the legendary EDM artist Au5 has a tutorial on it on Youtube, which you can find here.
Rather than copy his words, we’re just going to provide a summary, and you can check out that video for the in-depth explanation.
The hypergrowl is based around a square wave, so cue up your Basic Shapes on Oscillator A, then change the wavetable position to a square wave.
Turn Unison voices up to 9, and the Detune to about 0.11 (Au5 uses slightly different settings, these are just our favorite). You’ve just made a supersquare; congrats!
To make the hypersquare, we’re basically going to super the supersquare. To do this, find the Serum main menu in the top right corner, and find the option Resample to OSC A.
Click it, and you should see the single waveform is now a full wavetable, which is a rendering of the supersquare you made just moments ago.
If you turned off unison voicing, you could scroll through each frame of the wavetable and it would sound like the original, multi-voiced supersquare.
Now, take LFO, set the rate to 2 bars, and change it to a downward ramp instead of the default triangle. Assign this LFO to the wavetable position, and then resample yet again.
What this does is it renders a multi-voice render of a multi-voice render as a wavetable. Then we do it again, and a few more times to get a really watery, cool hypersquare.
Once you’ve had enough, you can turn Unison voices off and bypass the wavetable position LFO, and continue playing around with filters, FX, and other plugins.
Try adding the sub for some of that juicy low-end goodness, or playing with some FM to give it a little extra flavor.
Don’t forget that you can further modify these sounds in your effects chain outride of Serum with other plugins!
OTT by Xfer is basically the same as the multiband mode on the Compressor in Serum’s FX rack, and it’s a free plugin you can download and add on the end to really bring out the high end of a sound.
Be warned, OTT stands for Over The Top, due to its extreme nature. Some compressors are subtle; this one is not! Try out a filter, a unique reverb, or even a vocoder in parallel!
Use these techniques to get yourself started, and then take your sound design to a whole new level!