Formant filtering is a process that replicates the vowel sounds produced by the human voice. As a tremendous part of our speech, these vowel sounds are instantly recognizable and can sound quite eery and interesting when a sound other than the human voice produces them. Formants will sound neat with almost any source material, but are especially fun with growling basslines like those found in a lot of dubstep or drum and bass. The Fruity Love Philter boasts eight independent filters with an impressive array of modulation possibilities and can be put to use in series or in parallel. This makes it ideal for easily making morphing, evolving vowel sounds.
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Step 1
Select an empty mixer channel and put a Fruity Love Philter into the first FX slot. It will load with a phasing low pass filter with a pattern controlling the cutoff frequency, but we want to start from scratch. From the top left dropdown arrow, mouse over the Presets menu and select the Default preset, at the top of the list.
Step 2
Route something with a lot of harmonic content into the mixer channel. We’ll be setting up three relatively thin parallel bandpass filters, and the effect won’t be very audible with a pure tone like a sine or triangle wave. detuned saw waves from a 3xOsc will work very nice.
Step 3
The Fruity Love Philter will use any notes played on a MIDI keyboard while it’s selected to change its patterns, so make a new pattern and program a little melody or single note in. This way, we’ll be able to hear the effect while we’re tweaking it.
Step 4
Select the first filter and set the filter type to a bandpass filter by right clicking the box beneath the filter label and selecting Vanilla band pass. Set the cutoff frequency relatively low, somewhere near the fundamental frequency of the sound. In the end, we’ll be tweaking the cutoff of each filter to shape the sound, so don’t get too caught up getting it perfect.
Step 5
Since the first filter will likely be handling the fundamental, it should be a little wider than the rest of the filters. The resonance knob controls how wide the band will be, around 25% should be good.
Step 6
Select the second filter and enable it by clicking the On button on the left. Make it a bandpass filter and set the cutoff frequency a little higher than the first and the width narrower. If you move the cutoff frequency knob around a bit, you’ll begin to hear the vowel effect. When you’re done making “WooghhAuuughh” sounds, move on to the next filter.
Step 7
Again, set the third filter to a narrow bandpass type with a frequency higher than the second. The relationship between the three frequency determines what kind of vowel sound is made and you can find charts of formant frequencies for various vowels on the internet, but experimenting will yeild a nice sound almost every time.
Step 8
By now, it should sound like vowel, but a static vowel sound isn’t nearly as interesting as a morphing one. Go back to the first filter and click the Cut editor target box. Click the LFO box beneath and turn the LFO on by clicking the little circle next to the speed knob in the bottom right. Turn down the Env knob so that the LFO affects the cutoff frequency less and set the LFO’s speed to be pretty slow. Keep in mind that the LFO resets when the pattern mode loops, so you might need to make a longer pattern or put it in the playlist to hear the whole thing.Turn the cutoff frequency a little higher, if it needs it.
Step 9
An LFO on the second filter’s cutoff frequency might be fun, but a pattern would be even more interesting. In the second filter, enable the pattern controlling the cutoff in the same way as the LFO in the previous step, and zoom out with the mousewheel.
Step 10
To make editing the pattern a little easier, enable the Snap button in the bottom right. Right-click to add points to the pattern and make a nice ryhthmic pattern two bars long. Adjust the Env knob so the pattern doesn’t move the cutoff frequency around too much. Right click the last point at the end of the second bar and select Sustain loop end. Right click the first point and select Sustain loop start, this way the pattern will loop over and over.
Step 11
Click the menu button to the right of the Freeze button and click Copy state. We’ll be using the same pattern with the third filter, but edit it a bit to add some variation. Select the third filter and click Paste state from the same menu. Move some of the points around a bit and decrease the Env amount.
Step 12
Add a bit of warble to the third filter’s cutoff frequency by enabling it’s LFO and setting the speed pretty fast. The LFO amount can follow a pattern as well, right click to add points and vary the amount within two bars. Right click the end and beginning points and set the loop points up, just like with the pattern. If the LFO is too extreme, adjust the points within the LFO pattern, as the Env control is already keeping the cutoff pattern in check.
Step 13
Adjust each filter’s cutoff frequency, width and envelope amount until they sound good together. Add some distortion to really make it growl.
