For the audio transformation aspect of Signals and Stillness, I wanted to achieve an effect similar to one that I’ve worked with in Adobe Audition, where an FFT filter can be used to isolate particular frequencies, resulting in an ethereal musical-chord-like output created from any audio source (e.g., the “C Major Triad” preset of Audition’s FFT filter). I found a great starting point for this effect in the “Forbidden Planet” sketch of the main Max examples collection.

Specific values can be set in the multislider object to isolate frequencies using a “select” message – for example, sending the message “select 100 0.9” filters the output to frequencies between 4280-4320, close to a very high C# note. To have greater control over specific frequency choices, I’ve increased the value of the pfft sample size from 1024 to 8192.

Here’s an example of the resulting sound using the video clips as an audio source and creating random triads based on notes in a C major scale:

In the final piece, this filtered audio is routed into delay and reverb effects that change in their intensity based on the number of stationary observers and the length of viewers’ stillness.