How to Synthesize Vocal Sounds for Non-Beginners

Make your synth talk with subtractive synthesis and ring modulation.

Recently I discovered it’s easy to make surprisingly realistic vocal sounds, called phonemes, using any subtractive synthesizer and a ring modulator. When you think about it, doesn’t it make sense? A ring modulator creates two sideband frequencies that are the sum and difference of the carrier and modulator frequencies. Vocal sounds are created with multiple formant frequency peaks. In this application, the ring modulator sidebands are mimicking vocal formants.

The basic synth patch here is just a slightly resonant plucky sawtooth. Setting the mix low on the ring modulator allows this song to come through blended with the sideband/formants at just the right amplitude range.

This simple setup leaves a lot of room for exploration. As you can hear in the video, changing the envelope significantly affects “pronunciation,” and modulating the ring mod’s carrier frequency can be really fun.

I used the onboard sine wave LFO and the external sample-and-hold to modulate the carrier frequency, but you’ll find plenty of other mod sources. Try them. What happens if you modulate the carrier frequency with the synth’s filter envelope or use the synth’s audio output as the carrier? Let’s find out!

Postscript

I wasn’t trying to create vocal sounds when I stumbled on this phenomenon. I was just aimlessly patching to see what might happen and experienced a happy accident. I was listening intently, however. When I first heard something slightly vocal, I homed in on it.

The moral here is, “Listen closely even when you’re just goofing around.” You may find a lot to discover.

“These are your tools. They’ll teach you things. They’ll teach you things you don’t even know you want to know.” – Laurie Anderson