Recently got the Shnth, and love it so I’m branching out into other CL gear. Can anyone point me to a good walkthrough of assembling Meng Qi’s Namasitar? I think I found a BOM, but definitely need some instructions or walkthrough of putting one together. Thanks!

Jeez, what a great thread. Been thinking about diving into CL(etc.) instruments for a while. Bookmarking this for later research.

Still bummed that workshop at huds happened a couple of months before I arrived @Rodrigo!

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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.

I haven’t finished the build, but I did buy a cheap guitar which I modded (among other things) with the intention of building a Namasitar PCB into it.

I took the guitar to a luthier and had them route a channel right along the frets and then I soldered resistors to each fret to create the ladder.

I’ve not seen my PCB in a while, but from memory the PCB allowed you to use the onboard ‘stylophone’ or wire it up to an actual resistor ladder.

I don’t have any useful suggestions with regards how to implement it with a harp, but one of the most useful things about the fretboard ladder on a Namasitar is “fretting” multiple frets at once to create notes ‘in between’ the individual frets.

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Thanks, Rodrigo –

You can see that the PCB that Meng Qi designed for his stylophone Namastitar included the stylophone pads and places for all the resistors:

But the PCBs currently available assume that you are building the resistor ladder externally:

I can’t really read the values of the resistors he used:

How did you know what values to use for your resistor ladder?

I have a Namasitar, and took measurements years ago (and exchanged some emails with Meng Qi) about it. My original notes/sketches attached for the sake of completism.

It’s 10k resistors all the way down.

I have one of the oldschool Meng Qi PCBs too (which I bought to build into the modded guitar), which I remember being designed in a way that you could just bypass the in built stylophone bit.

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Thanks, Rodrigo –

Okay, that might change everything. On the PCB the spot to connect the resistor ladder is marked “10K ladder.”

I interpreted that as a resistor ladder equivalent to a 10K variable resistor, but instead it now sounds like a resistor ladder made from 10K resistors in series (in the stringed instrument version, complicated by having multiple “styluses”), with the fretted version having 15-16 resistors and the stylophone having 21. So if I want to use a ribbon control I’ll have to figure out how to scale up the resistance (use the softpot to control a digipot or something).

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So, I have a Shtar, and I am trying to send some binaural field recordings through the dual CV/audio inputs… But I’m having trouble getting it to work… top and BOT are supposed to be the inputs, and it seems like I need to put wind inside of them, and then mul it, But I am still not getting results other than a very faint hint of signal when I press the strings to the fretboard, which isn’t part of my initial patch, any ideas? Thanks!

I don’t have a shtar but if you post the code up or just a picture of it I would be happy to take a look

Ya know, it turns out to be some weird problem with the splitter I was using, apparently it wasn’t the L/R splitter but some other function…

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so those inputs can be used for audio and CV?

Well, according to bartlebooth, anyways, yeah…

I def got audio through em, but not the way I wanted (l-r binaural)… I ordered a new adaptor, should Either fix the problem or at least let me rule out that it wasn’t the fault of the adapter that it’s kind of not working still

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hey, could you show me a patch that would get stereo line level audio cleanly through a shnth? I could extrapolate from that maybe …

got a response:
“well, let me explain something, the adc inputs on thos top/bot auxes are
not gonna be past a telephony (shitty) audio rate. since they are muxed
with the knobs, primarily a gesture input, it is not really for processing
audio but instead, for taking cv inputs from eurorack for example. does
that make sense?”

-PB

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oh bummer
thanks for posting this info

one handed FISHING, Plank expression derives the bits from each fret, adds em into values, I believe… I think it’s like adding MWRS bits to get changing CV on PB, but still experimenting

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fyi i posted as many old patches as i could find (from everybody) plus the Fish and old Fish Software here :slight_smile: Now i don’t particularly like the new V2.0 Fish (shobobo.zip) as it has removed random duplicate option, but there are some example patches in there that really are great - which i copied to the patches folder and do work with Fish V1.2 which i use currently.


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very helpful, thank you jason!

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20 chars of Thanks!!!

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i didnt try Fish v2 yet, but as i understand you dont need random duplicate option because…

“Note that the previous version of Fish had randuplicate, and this has been eliminated because Tank and Boat will be bearing the burden of generating permutations of patches.”

the problem is that…

" They are not implemented yet, but Tank will be for listing things and Boat will be for scripting things in classical Lisp, thus the possibility for generative patches. "

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