Polyphonic NE555 instrument - 5: The big finish and demo

The demo starts at 4:15 - and this time no sqeaking! (but a little out of sync)

So the time has come to finish this project. The electronics I make this time doesn't take as long to assemble because it is common for all the keys so there is only two of most of it - one for each channel and the instrument is in stereo, instead of the 24 that I have made of everything so far.
I only had one mishap during this final build: It turned out that the indicator lamp in the mains switch was just an LED even though it said '230V AC' on the side of the switch, so when I switched it on it went SCHRRRRTCH, and then I had to find another switch, this time with a good old neon bulb inside.

The music is something I played on my Elka EP-8 organ and Yamaha SY-1 synthesizer. I added a little modulation with my BOSS ME-50 pedal.