MIDI to Gakken SX-150 Interface

Thomas_Henry · Last edited by Thomas_Henry on Sat Jun 25, 2016 11:28 pm; edited 1 time in total

Hello All,

I (finally!) had my project appear in Nuts & Volts Magazine. That's been over a year awaiting...Anyway, should you happen to own the neat little Gakken SX-150 Mark II synth, you might enjoy this. It adds MIDI to it. The tuning is remarkably good for such a simple affair (over four octaves).

Anyone, including non-subscribers, can preview the article. Just click on the blue mouse icon. Subscribers can read the entire thing. Also, the PCB and source code files are available there in a zip file for everyone.

http://www.nutsvolts.com/magazine/article/April2016_MIDI-Analog-Synthesizer

On another topic altogether, and at the risk of massive immodesty, may I also mention that I've posted some highlights of my forty years in rock music on a blog? Should you be at all interested in how someone can survive being a hack in the world of rock and roll, take a look. The link takes you to the rock biz stuff:

http://spurtsofink.blogspot.com//2014/11/journey-end.html

Thomas Henry

sneakthief · Joined: Jul 24, 2006 Posts: 569 Location: Berlin

Thanks Thomas for the fabulous road stories! It's especially titillating to read as a touring musician.

earo · Joined: Apr 19, 2011 Posts: 13 Location: haifa

Hi Thomas - thank you for posting this! I'm surprised that the Gakken synth didn't get more attention on this board.. there are loads of mods on the net that make for an interesting little synth..

Do you think this will work with the original Gakken SX-150 as well? (I realize I'll have to deal with the EG/VCA differently).

Thomas_Henry · Posted: Sat Jun 25, 2016 11:32 pm Post subject:

Hi Earo,

I'm not familiar with the Mark I, so can't offer much advice. I recommend you monitor the stylus probe with a multimeter and see what the voltage range is. If it's +2.5V to +5V at the extremes, then my interface should work (at least for the CV stuff--I have no idea how the envelope generator is handled).

Thomas Henry

earo · Joined: Apr 19, 2011 Posts: 13 Location: haifa

I will do that! Thank you for your reply.

Allow me also to thank you for being such an amazing teacher and contributor to the SDIY community. It is your work that really got me going in SDIY and for that I'm forever thankful!