Oscillator that its pitch changes based on the pitch of audio input

Hello all, I’m trying to find a way to create a patch where I send a bass guitar signal audio input from my sound card, it triggers an oscillator and the oscillator’s pitch follows my bass guitar’s pitch (or differently put the oscillator’s pitch changes every time my bass guitar’s pitch changes). Anybody has any ideas on how to get this work?

Thank you.

Nysthi and Entrian both have pitch-to-voltage modules.

For best results, I would run the input through a low-pass filter to stop it from glitching.


What frequency would you set the filter?

I used to start about 1K and adjust until I got what I wanted to hear. That was with a voice. You may want to go lower for a bass.

Maybe try it into the sync input of an oscillator (like Terrorform)? edit to be clear I mean the Bass signal itself into the sync input.

I could’t resist… the comparator threshold is adjusted to trigger the sample&hold for the pitch to voltage between notes. The note detection can also be adjusted with attack/release on the “Blindcurve” audio detector.

It takes a bit of adjustment to get it just right … great fun.

Pitcxh_F0llower.vcv (16.1 KB)

PS. I didn’t figure out how to mimic the amplitude of the source signal.

This is not something I’ve ever done but it was on my list of things to try and I always assumed that I would need an envelope follower for the amplitude.

edit: looking at your diagram it looks like you’re not talking to me but the envelope follower suggestion might still work.l

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Can you make an envelope follower with a rectifier and a lag unit?

This edit tries to follow the amplitude of the source. (and adds a bit of motion to the voice).

Pitcxh_F0llower_2.vcv (19.4 KB)

I would like to change it to trigger on peaks , and not just when the value exceeds a threshold. But i would need a time machine, i guess, to detect peaks in a live signal without delaying the trigger.

If it’s only 10 ms. Or something it can work fine.

I don’t know. If I didn’t use the Bogaudio Follower module I’d use a slew limiter with rise and fall controls.

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You would need to rectify first, or it would do nothing. But if there is already a flood module, sure.

This can make quite a racket given some pitched audio


Will have to try that PLL module! I use guitar with rack, and made a few guitar synth patches using Entrian Follower. I found that it doesn’t really track well enough to be much practical use. I bought a Boss guitar synth pedal instead, and run it through rack for effects. Dag2009’s suggestion of sticking the audio into VCO sync input is a great idea too, that makes some cool sounds without worrying about the tracking. I also made a cool synth bass patch using Warps (Meta Modulator) internal oscillator, but again it doesn’t track perfectly.