QuadSID, finishing touches

Time for lé complétion féstivál, as the unit now sits on my desk happily playing Für Elise over MIDI! Not really the prime choice for this synth, but that’s the first .mid I came across ;) .. nonetheless, yay it finally works 100%!

Editing the software didn’t go as smoothly as planned, needed a few sessions to get it right. Whilst fiddling with the software, it also turned out that the filter/envelope buttons and encoders had problem functioning smoothly (messages vanished after the 10th chip in the DIN-chain) so I ended up re-doing parts of the cabling for these. As with the banksticks, all the other schematics/layouts were also lacking the 100nF bypass capacitors next to all digital IC power supply pins, so I added some SMD ones. Placing this capacitor next to each digital chip is a common practise to smooth out / suppress digital noise leaking to the common ground.

So to round up this project, here’s the remainder of the work-in-progress photos followed by a few shots of the complete synth:

Enclosure parts painted and ready for final assembly

100nF bypass/decoupling capacitors on one of the SID boards

A piece of plexi mounted using some hot glue, surely the display needs a window!

A view of the internals

And the completed unit \:D/

To list a few statistics for this synth, it took 37 building sessions and around 90 hours to complete all-in-all. Around 10 of these hours were used to fixing hardware and software errors. Maybe this gives you a bit of idea about the size of this project. You know, just in case you happen to consider building one yourself ;)