It took me a day to adjust the size, prime and paint the pre-laser-cut Otomixer main control panel. After assembling empty vials and plugging in the headphones, the device looked like this:
I took me several days to seal all the vials and pour the liquids into them. I used three food colourings (yellow, green and red), potassium permanganate (purple) and india ink (black). Vials are sealed with a termoplastic resin, which I got from my grandfather (it was used in Polish radio industry in the '70, but still does an excellent job).
Soon afterwards I started to assemble all necessary electronic components. Eventually, I manage to fit in 2 amplifiers (based no the stethoscope design that I build before) and an equaliser (5 band, instead of 6 band, which I used previously, but this is still the same circutry). It works all fine, and is pretty exciting when you can equalise the same voices you can normally hear around you (it's actually live equalisation). Unfortunately the differences in frequencies are not that distinct (even though I used capacitors ranging from several hunderds of pF to 10.000 times stronger ones of uF value)... This is something I might want to work on later on, improving my electronic circutry skills at the same time.
