Last night I spent my evening hacking at Pumping Station: One, Chicago's premiere hacker/makerspace. It was my first time really getting down to work there after joining a few weeks ago. What I love about working there vs. at home is the community. A couple members, Steve and Patrick, who much more experienced in electronics than me were incredibly helpful, teaching along the way. I wouldn't have had this first success without their help.
So what am I making at PS:One? Well, in short it is a MIDI-controlled channel selector for my guitar amp. Anyone who's ever seen my guitar rig will usually comment on my pedal board first. For all the complexities you see at first glance, it's actually rather simple and elegant. A few years back, I bought a box that plugs into the amp that selects between its clean and distortion channels. Then I started it on fire. I've since replaced the fried diode inside it and it works again (also thanks to the guys at PS:One), but in the process realized just how simple it would be to build one of these boxes myself. My guitar amp has three quarter-inch mono phone plugs, one for each channel. When the tip of a cable is connected to its ground (i.e., shorting the cable with a SPST switch), the amp switches to the corresponding channel.
Thus, the goal for my project is simple: Build a box that will receive MIDI program change (PC) messages and select the desired channel on my guitar amp (clean, rhythm, or lead). For example, MIDI PC 11 would be the clean channel, 12 would be rhythm and 13 would be lead.