pd27. High-pass filter in Pure Data

A high-pass filter can be implemented with the hip~ object.

There are two audio sources here, the noise object (white noise) and the pink object (pink noise).

The toggle switch controls which audio source is used. Initially we check the toggle so we hear filtered pink noise. Clicking on the bang, which activates writing as well, will turn off toggle and then turn it on 0.5 sec. later. This way 0.5 second is spend on each audio source.

The top of the graph shows the audio in Waveform view. The first 0.5 sec. are high-passed white noise, and the last 0.5 sec. are high-passed pink noise. From the spectrograph view, bottom, the more uniform distribution for pink noise portion can be seen.