Hi! Here is a little something-something that i've been thinking of. I thought about making a breath controller for my upcoming midibox, and looked at Matteo Bosi's design at the MIDIbox Extensions page. I love his concept8), but it uses a pressure sensor that costs about 40 Euro in Sweden. And that was a little too much for a poor student like myself. However, i thought about making a breath controller that uses a light sensor instead, like this one: http://www.elfa.se/elfa/produkter/en/2016264.htm The concept looks like this: The idea is that a valve (made of i.e. some thin, flexible, non-transparent plastic or metal film) shuts between two chambers (one with a LED and one with the sensor) and then bends open when air presses it, thereby letting the LED illuminate the sensor, in relation to how much air is blown into the device. The main advantage of this device is that the cost of the optical sensor is a fraction of the price of a pressure sensor. As i understand, the sensor also has it's own amplifying circutry. I havent built this or anything like it. I do not have much electronic knowledge, so i don't know about how the circuit diagram should look like (or if this solution is even possible at all???) What do you guys think? /J