Just an idea, but was thinking how fun it would be to have a ribbon controller that sat above the keys. Could run it into the expression pedal input, and assign it with the mod matrix. Could stick it down with that magnetic sheet stuff.
Just in the daydreaming stage, but for a diy thing I would want to use one of these 500mm membrane potentiometers:
https://www.sparkfun.com/products/8681I think you could wire it up quick and dirty, without other electronics, like an expression pedal, but it wouldn’t be able to hold its position when you took your finger off. Could still be fun though! And easy. To hold it you would need a whole circuit, either an analog sample and hold thing, or a digital programmed thing like Arduino, which might be better, if the softpot had a tendency to drift as you take your finger off it.
They have pressure sensors that could go under the pot, that could do a separate thing through expression pedal #2 input, like volume, or filter, etc. if you were doing pitch cv with the softpot:
https://www.sparkfun.com/products/9674Here’s a nice Arduino project, that almost fits the bill, but it seems to be a midi controller, rather than CV, and I don’t think we would be happy with regular 0-127 resolution on something like this, though 14 bit midi could be very nice and not use up the expression pedal
http://www.coagula.org/albedo/how-to-build-a-midi-ribbon-controller-with-arduino/If you did do it as midi rather than cv, you could come in as macro knob 3 and/or 4, on midi cc# 4 and 3, respectively. In the midi control center for the MxB you can turn on 14 bit midi receive, and get smooth, fine movements.
Ideas?