How to detect an LFO (low frequency oscillation) signal into the ETC?

ETC
1

Hello!

Suppose the audio signal into ETC contains an LFO (low frequency oscillation) signal with frequency f and amplitude A. How can I compute both f and A?

Best regards,
rodde

2

You can’t. The audio input is AC coupled, so the LFO signal is filtered out. I assume the lowest recognized frequencies are around 30Hz, below that the signals will become the more flattened the lower their frequency is.

Using the amplitude is possible if you use the LFO to control a VCA. Send a constant audio signal through this VCA and then send the output of the VCA into the audio in of the ETC

If you want to control the ETC with an LFO from a modular system or similar, then you have to convert the voltage into MIDI-CCs that correspond to the buttons.

Additionally you could extend the count of recognized MIDI-CCs by editing the in the ETC_Mother/midi.py
Change
“cc_last = [0] * 5” to “cc_last = [0] * 16”
and |
“for i in range(0,5) :” to “for i in range(0,16) :”

Now the ETC listens to controllers from 21 to 37.