Hey there !
Recently created such a topic on Elektronauts, explaining how happy I was to have assembled a Shruthi-1 and a PreenFM2, after a
few guitar pedals…
Both synths were about 200€ the kit, easy to assemble and much fun to play with !
Plus it’s so cool to play on something you built yourself, when it works without any pb (which is the case for the 2 kits I’ve soldered)
I’ve just seen
@mixrasta talking about a small DIY device for using a simple MIDI keyboard on the OP-1… This would be very interesting !!
I don’t think there is such a thing as a DIY thread on this forum, I haven’t found it at least.
So, here is a place to share all your creations, plans, etc… DIY !!
Cool idea LD. When I get two minutes to myself I’ll be soldering together a midi sprout device.
You can connect it to plants and convert their “bio data” to midi! I’m looking forward to jamming with vegetation haha!
Hey I love DIY audio! I’ve made a few accessories to complement all my tiny instruments, so maybe they are of interest to people here.
First is a dual headphone amp in an Altoids tin. One stereo in, two independent drivers and volume controls. I built this one so I could play at my friend’s house without bugging her roommates 
One flaw is that you can’t actually close the lid, cause the 9V battery is too bulky. I have an improved design based on AA batteries, but I haven’t gotten around to making the PCBs yet.
Next is a tiny mixer, 2 full stereo channels, also in an Altoids tin. There are two output jacks so you can connect one to a speaker and the other to a recorder, for example. This one actually closes properly so it’s super portable.
Last is a portable mic preamp, which I made specifically for connecting a pro mic to the OP-1. This one doesn’t have an enclosure cause the XLR jack is too big for an Altoids tin. Dynamic only, no phantom power.
Nothing too exciting, but they all come in handy.
@macfergus! cool! do you have schematics or something? did you buy kits? where from?
Yeah, I’d be interested in that preamp to stick in a tin, bit with a jack input.
Top subject ! <3
What’s is your advice for my first DIY kit ?
You can use a raspberry pi to route midi signals. I use several throughout all my music related gear.
As a first DIY kit, I would say maybe try one of Techniguitare pedals, such as the Analog Delay (mono) or even a dirt pedal such as a Screamer or a Fuzz pedal.
If you don’t take the box (= you just want to develop your soldering skills) you should get a kit for 45€ with transport fees, iirc.
Techniguitare is a French forum so you should find some documentation pretty easily.
Shruthi-1 was very easy to solder, on
TubeOhm you can find the complete kit for 166€ (transport fees included)
Add a case and you go for +32€ so almost 200€ in total.
Just came across this video of Ambika, Shruthi bigger sister : I looove the sound of it, one day I’ll assemble this poly synth !!
@speckdrum @daninski I posted the schematic / board layout / part list for the mic preamp here: http://www.ofrecordings.com/2016/09/06/portable-battery-powered-mic-preamp/ if you want to take a shot at building your own. I just put the instructions together really quickly so please feel free to ask questions if I missed something.
I’ll upload the designs for the headphone amp and mixer soon if people are interested, just haven’t had time to write them up yet.
All Mutable mini DIY synths have been discontinued 
@<a href=“https://www.operator-1.com/index.php?p=/profile/691/quarantequatre” class=“Username” style=“margin: 0px; padding: 0px; border: 0px; outline: 0px; font-weight: bold; font-size: 15px; font-family: “lucida grande”, “Lucida Sans Unicode”, tahoma, sans-serif; vertical-align: baseline; text-decoration: none; color: rgb(1, 115, 198); line-height: 22.1px; background-color: rgb(252, 252, 255);”>quarantequatre<span style=“color: rgb(37, 38, 30); font-family: “lucida grande”, “Lucida Sans Unicode”, tahoma, sans-serif; font-size: 13px; line-height: 22.1px; background-color: rgb(252, 252, 255);”> Mutable Instruments DIY synths are now distributed by TubeOhm, so they are not totally dead yet
I fancy doing the Twisted Electrons Cheshire Kit with my little girl when she’s a bit older. Looks cool.
http://twisted-electrons.com/cheshire/
@mixrasta nice work, what kind of wood did you use ? Did you make this from the mutable instruments plans ? (http://mutable-instruments.net/forum/discussion/7514/diy-usb-host-midi-din-converter-usbpal-released-/p1)
Have you find why the sync didn’t work ? 
@steveoath what a nice idea !
It’s just cheap thin birch wood glued together and some Graffiti on top of it ; )
I have no idea why the sync is not working. Maybe one component is missing and was not ever meant to be implemented…
No, someone posted a link to someone’s pdf on Fb, this guy made it to control other gear with his novation circuit @quarantequatre
Shouldn’t sync be as simple as a click? I understand the original sync was a semiquaver pulse, maybe shorter, used as a pulse CV in one of the very expensive 16-tape channels which made part of Donna Summer’s I Feel Love… ain’t it?
@<a href=“https://www.operator-1.com/index.php?p=/profile/1820/steveoath” class=“Username” style=“margin: 0px; padding: 0px; border: 0px; outline: 0px; font-weight: bold; font-size: 15px; font-family: “lucida grande”, “Lucida Sans Unicode”, tahoma, sans-serif; vertical-align: baseline; text-decoration: none; color: rgb(1, 115, 198); line-height: 22.1px; background-color: rgb(252, 252, 255);”>steveoath<span style=“color: rgb(37, 38, 30); font-family: “lucida grande”, “Lucida Sans Unicode”, tahoma, sans-serif; font-size: 13px; line-height: 22.1px; background-color: rgb(252, 252, 255);”> this is awesome ! Can’t wait to build this with my son !!!
@lyingdalai I think it will be great fun with kp mini or reverb/delay pedals. Good fun Intro for the little ones.
It's just cheap thin birch wood glued together and some Graffiti on top of it ; )
I have no idea why the sync is not working. Maybe one component is missing and was not ever meant to be implemented..
No, someone posted a link to someone's pdf on Fb, this guy made it to control other gear with his novation circuit @quarantequatre
Thank you for the solution.@mixrasta
Here's a case for you with a 3d printer.
http://www.thingiverse.com/thing:1760483
