The most recent was adding CV IN's to a Shruthi-1. The thing with those is the CV IN traces go right to the Atmel Processor, which can only handle up to +5V. +5.01V and it's toast. Any negative voltages end with the same outcome. But, with the right protection, it should work. So, after discussing this with the Official MI Case Maker, a simple circuit was devised. Thankfully I have a spare Digital Control Board, so worse case scenario, I have an extra Atmel. I wired the jacks up, took a deep breath and sent it some voltages from the dotcom. The Shruthi stayed the course! Not a flicker or a twinge! I was quicky setting up different destinations in the Mod Matrix and using the dotcom oscillator as an LFO and getting some great results. Couldn't have been happier. Especially since I had ordered a custom case with 4 CV IN holes.
At any rate, now that it has been fully tested, I can now add this to the list of additional mods available for the Shruthi.
More pics here