More Fun Audio Analysis Techniques

Audio analysis used to drive LFO and movie rate sliders to create complex FX behaviors.

Using individual plugins to directly automate the control of different aspects of a live VJ performance or interactive installation can create some pretty awesome results, but one of the most powerful capabilities of VDMX is the ability to connect these plugins to each other to create more complex behaviors, interactions and visual effects.

For this set of tutorials we'll look at a few ways that the Audio Analysis plugin can be used alongside the LFO plugin and other standard interface controls as a demonstration of this technique.

Tip: Keep in mind that this same idea can be applied to other types of control plugins such as step sequencers, or with external controllers over MIDI, OSC, and DMX.


To begin we'll add an audio analysis plugin and load in some media files to work with. The first trick will be to use the provided data-sources to drive to rate slider in the movie controls so that it only plays forward when there is an audio input. Alternatively the time slider can be directly driven by the values to scrub through the movie.

Next the same technique will be applied to an LFO plugin such that it only progresses forward or scrubs through the timeline of a waveform. By making a more complex piecewise waveform made up of sine waves of different frequencies and amplitudes we can make visual FX that become more intense as the audio level increases. This is particularly useful for FX like bump distortion that wobble around a center point.

Lastly we'll use slider presets to set up keyboard shortcuts for toggling each of these automations on and off during a performance.


Tips and Notes:

Create piecewise waveforms for the LFO in the UI Inspector window.

Choose the “Peak Frequency Magnitude” or a specific filter range.

Slider Presets can be used to toggle automations on and off.