Natron may not be the best candidate for that, as there is no audio playback.
There is this plugin : https://github.com/olear/audiocurve that allow you to take a sound and make a curve from it, so you can map it to whatever effect you want.
But without proper audio playback you have to export the project to see what the result looks like with sound.
Blender as at least audio support, you can also take a sound and make an animation curve from it in the same fashion.
It can be very efficient if you animate shapes rather than 2D effects like for instance blur. Because if you apply the animation to 3D objects you'll see the result in realtime. For 2D /compositing effects Natron is better because it as realtime playback, where blender compositor is not well designed for that, but without sound.
Adobe After Effect is very well suited for that kind of tasks, with blender and natron there are indeed workarounds , and you can get very nice results, but it need patience