DIY : tsnm (Touch Sensing Note Memory) by Doboz


For this piece:

74HC595 2 IC1, IC2 SOIC-16 shift register
Mouser ref number: 595-SN74HC595DR

There are multiple parts that come up, with different options (# of circuits, logic type, # of input lines etc)
Any ideas?


I’ve commissioned a built one to @Gregory_Delabelle, awesome belgian builder that has served me well in the past.


I’m in the states, but I’ll keep this in mind!


whooaaaaa. this looks amazing. I saw something about it awhile back but this demo vid really shows it off! I need to ignore it for now and finish some other projects first, but definitely planning to build one and may eventually be able to build for others.

In the meantime, for folks in the USA (cc @stripes, @Jonathan_Riley), consider checking with Raph at Michigan Synth Works if there isn’t someone here to do it already. I don’t think he’s on lines, but he is ‘Altitude909’ over on MW. I haven’t bought from him, but he has been very helpful for all sorts of DIY stuff over the years on MW and the Mutable forum and I have only heard/seen good things about his builds!


Anyone used a Prizma, also from Doboz?


As far as I know they all will work. Normaly I go for the one that has no extra letters at the end. In this case the 74HC595DR:

But I would be happy if someone with more expertise can bring some light


i love the look of it and it seems to have much of the same functionality as my SQ-1 plus more but with 100% better syncability [which has been an issue for me lately]. i’m curious about its usability.


I’ve bought from Raph! He actually lives 20 minutes from me. Highly recommend him.


All sold ut, but you can get on the waiting list of course :wink:


Aaaah… and I just contacted “my” builder that is so excited to build a couple of these.


is there a mouser or digikey BOM somewhere?


I’m starting to look over the BOM – the following parts are out of stock on mouser, any ideas?

1u x1 (C14)
0603 ceramic capacitor, >16V
Mouser part #: 581-06035D105MAT2A

MMBT3904 x1 (Q1)
SOT-23 NPN bipolar transistor
Mouser part #: 512-MMBT3904



i recommend octopart for building a bom, as you can cross check stock across a ton of suppliers…


Ahh nice thank you very much, great site!

I still cant get that MMBT3904 — the places that ship to the US, have min orders of 1000+ and its out of stock everywhere else.

I have this feeling there must be a comparable part with a different name, I might contct doboz and ask about it. Hmmm


Like here is the T version on mouser:

The “Collector-Emitter Saturation Voltage” is not listed for this part, otherwise it seems the same… i dare not try it. Haha


2n3904 is the generic name for that one. Looks like it’s just a buffer for the trigger input, so almost any general-purpose NPN transistor will work (eg BC549).


Thanks @Galapagoose — Is there a specific one you would recommend?

I’m feeling pretty useless here …:roll_eyes: the shapes being different is probably of zero consequence, but makes me feel unsure. :sweat_smile:

I really want to do the build myself to see if I can, and I really appreciate the help everyone!


@Galapagoose/someone else can certainly correct me if I’m wrong, but I think this would work fine, is in stock, and is cheap.


That will work. There are a lot of 3904 transistors from different manufactors. Just be sure it is sot–23


MMBT3904 is the name for the smd version of the 2N3904 transistor which is through hole.


Thanks all. Much appreciated!