Controlling external software synths with MIDI



Is it possible to control external synth’s from sonic pi? I know you can send midi notes, but I am wondering if it’s possible to control a synths ADSR or any other knob/slider from Sonic Pi?

I’d be trying this out in ableton using the omnisphere 2 vst synth.

Thanks for the help!


Connecting to VST Host
Is it possible to control via Sonic Pi an instrument in Ableton?

Hi there,

which external synth(s) are you trying to control, and what API(s) do they support (i.e. OSC/MIDI)?


I’m trying to control Omnisphere 2 and it supports midi

Thanks, Sam!!


Which OS are you running?


I’m using apple, osx yosemite on a macbook pro.
And am using Ableton for my daw


Ok, then you just need to enable the built-in virtual loopback midi port to let you send midi from Sonic Pi to another app :slight_smile:




A quick google turned up this which may help:


I got things set up and it’s all working! Midi CC messages and all.

An infinite amount of thanks to you, Sam!


Fab stuff - I love the video :slight_smile:

Btw- top tip - if you find yourself combining in_thread and loop chances are you’ll be better off just using a live_loop instead!


I’ve been playing with the super donate-ware synth HELM with Sonic Pi 3 on my Mac. Here is a video showing two parameters (volume and bpm) of the synth being controlled. Any of the other knobs and sliders can be controlled in a similar manner. Links to the code shown in the text below the video.

More Sonic PI and HELM synth

Thanks, Robin! You have had the answers to all my questions