It’s hard to make an audio mixer with any less technology than FingerRing (YouTube video, embedded below). We’re pretty sure that [Sergey Kasich] isn’t going to get a patent on this one. But what he does get is our admiration for pushing a simple idea far enough that it’s obviously useful.
The basic idea is transmitting signals using the human body as a conductor. What [Sergey] does is lay out multiple sound sources and sinks on the table, and then play them like a mixer made musical instrument. Pressing harder reduces the resistance, and makes the sound louder. Connecting to two sources mixes them (in you). Watch the video — he gets a lot of mileage out of this one trick.
We can think of a number of improvements to this system. A bunch of nails in a board acting as the contact points would be a lot easier to play than 1/4″ cables taped down to a desk. You could make it a permanent instrument. If you were designing the system from scratch, you’d want high-input-impedance amplifiers on the receiving end. Add a notch filter to kill the mains hum, or an instrumentation amp and another electrode on your ankle. Pretty soon, you’re an EKG and a mixing desk.
The biggest limitation he has is that the body is just one big conductor. Can anyone think of how to get multiple channels through flesh and bone without making the whole setup over-complicated? Now excuse us as we tape instrument cables all over our desk. We’re inspired.