Simple 12 db low pass filter.
This filter use 2 BC547 NPN transistor and a stereo 100k pot
for the cutoff, instead of the pot. it's possible to use 2 photo resistor.
This filter is calibrated for 5v use but also 9\12 volt for simple application.
I've develop it with Peppo at LEP lab. in Milano.
I use it in this 6 bit noise generator, video.
Val Pastel made this filter audio test listen
A small revision for the 12 db filter, this schematics is calibrated for 12 volt use.
Here you can found an eurorack version made by Danny of TAT on Etsy
Here an High Pass version of the same filter.
