12dB/oct Vacuum Tube VCF (no semiconductors)
A wobbly demonstration of a filter I designed. I'm not aware of anything that might be like this (I tend to work in a vacuum... no pun intended) so please comment if you're working or know of something similar. It'll do 24db/oct, however that'd need an additional four tubes which I don't have at the moment.
The synthesizer I'm using is my DIY one I made in 2011. It's developed a fault where the oscillator CV won't go above a certain voltage, so there are a few dud notes in this demonstration.
I might make a Hackaday Projects page for this.
EDIT: https://hackaday.io/project/163761-va...