Your Namastitar question might be more on topic in the general Ciat-Lonbarde thread: Mobenthy/Ciat-Lonbarde (synthmall) thread . There might be more people following that thread, too.
I bought one of Meng Qi’s Namastitar PCBs and my current plan is to install it in the soundbox of a three-octave (diatonic) wire-strung folk harp I bought long ago. (Off-topic aside: It’s triangle shaped, which means a linear increase in string length, which is non-optimal for a harp. It means that it has more steel strings and fewer brass strings than one would want). A contact mic attached beneath the top of the soundbox would go to the PCB’s inputs and a audio jack at one end of the soundbox would be wired to the outputs. I would be mounting the pots along the side of the soundbox instead of directly on the circuit board.
My question involves the 10K resistor ladder. I’ve never seen one of Peter’s original Namastitars but my understanding is the the frets were the equivalent of the contacts of a stylophone and the strings were the equivalent of the stylophone’s stylus. This is really elegant because the same action – fretting the string – affects both the acoustic and the electronic functions of the instrument.
Meng Qi’s version used a stylophone approach for the resistor ladder, but his PCB doesn’t include the stylophone portion so we don’t know what resistors he used to sum up to 10K. This is comparable to Peter’s Namstitar paper circuits which treat the resistor ladder as a potentiometer. I haven’t actually heard of anyone else completing this instrument besides Meng Qi, so I don’t know what they did for this.
With a harp, I don’t see a way of using the strings as a stylus, and a stylophone interface would be too awkward. At the moment, I’m considering using a 10K softpot in place of a resistor ladder. This could run alongside the bottom of the strings so that one hand can pluck while the other controls the ribbon control. I just don’t know how well this would work. The resistance of a softpot would increase linearly from 100 to 10K ohms – I won’t know if this provides playable control of the circuit until I wire it up and test it.