Frequency filter idea


I’m wondering if it would be possible to have a frequency filter inside the ETC, such that it would only receive (for example) frequencies below 300hz, or frequencies between 500 and 1000hz, or only over 5000hz.

I think this would make the visuals a lot more sparse. A lot of the ‘modes’ look great with one instrument, but become quite hectic when you input a full track.

Anyone think this is possible?


That is a good idea, especially allowing only low frequencies. you could add a simple low pass filter into the python code for each mode (it would just preprocess the audio input buffer). unfortunately there isn’t an easy way to add it to all modes without hacking the underlying system.

Hello Dominic,

I use now a Alesis Filtre (from the ModFX series). It is a great improvment for the visuals

Neverthelss I’d be interested, whether a python based filter would work. Unfortunately my math is not very good. Must be something with integral over the audio… uuuh, please someone else jump in :wink:


does the etc image have scipy installed?
(dont have an etc image to hand)

otherwise, you could knock up a very simple moving average filter.

[‘cherrypy==5.1.0’, ‘packaging==15.3’, ‘pip==8.1.0’, ‘psutil==5.0.1’, ‘pyalsaaudio==0.8.2’, ‘pygame-sdl2==2.0.0’, ‘pygame==1.9.3’, ‘pyliblo==0.9.2’, ‘pyopengl-accelerate==3.1.0’, ‘pyopengl==3.1.0’, ‘pyserial==3.0.1’, ‘setuptools==18.5’]

unfortunately not by default