A friend of mine send me a pcb for a 3350 Chip filter. This filter was based on the digisound 80-16. I was the start for me getting into a search for 3350 filters. This chip is used in the Sytron Syrinx and I really like the sound of it from what I could find. There isn’t much info on this chip and old filters that use it. But I did find someone that took the datasheet schematic and used it in his synth. PolyKit made a 8 voiced synth called the polykit-6 (check out his YouTube and GitHub).
I used his schematic as a base for the Untamed (with permission). Basically Untamed is the schematic from the datasheet of the AS3350 chip, with controls and a eurorack panel. It has it’s quirks but also a unique sound. I called this Untamed cause of the little quirks and raw sound that make it unique. I don’t think it tracks 1v/octave but it sounds awesome.
I would like to thank Polykit for his generosity and putting his work online. I will put the schematics up for everybody to look at. To comment on for further improvements and maybe come to a new module that is a bit more Tamed. The files for the pcb’s to order your own will be released after 10 sales.
I uploaded most of the bill of materials to the website. These are also on GitHub but no need to download the full repository’s if you don’t want to. If you are looking for one of the modules bill of materials you can find them here after the read more
I didn’t have any sample and hold module in my rack. At first I didn’t think I needed one. But seeing a few video’s of what you could do with them I just wanted to have one. A sample and hold basically takes a voltage and when triggered it send the voltages to the output and keeps it at that level until next trigger,in theory. But being in a analog realm the capacitors used to keep the level at the output steady lose there voltage slowly and the voltage keeps dropping. This can be overcome making a digital sample and hold or just to use a quantizer and hope the next trigger will come before the next note is quantized. In practice the last option fits most purposes. So I decided to build a analog sample and hold.
I have been working on a filter design. The design is based on a new version of the cem3350 chip. The cem3350 was used in the Synton Syrinx, Rhodes Chroma and a few more synths. It hasn’t been used that much and the chip is somewhat of a niche filter. This chip is in production again by Alfa as the AS3350. That gives opportunities to design a filter based on this chip. The design isn’t complete yet but the pcb’s came in yesterday, so I was able to do some testing. Found out that the cutoff knob is reversed on prototype. I have been testing it together with the reverb I’ve posted about last week, to give you all a bit of a teaser of what’s to come.
The patch is Braids “VOWL” into the filter to the Reverb.
I was looking for more effect units in my rack. As I’m a big fan of DIY there aren’t that much choices. Lucky I found the kxmx bluemchen. A small module, open source and with a Daisy on the back. I did not know about Daisy and it took me on a journey. Oh I went into a rabbit hole last few weeks.
The website where you can find it advertise it as ” the go-to DSP solution for your next audio project.” I looks a bit like a Teensy or Arduino Nano. It took my interest. I soon found out it can do a lot more then your average Arduino. Daisy is made for working with audio it’s a digital signal processor (DSP). Meaning it can do a lot of things with audio signals. It can even be the source of a audio signal. They also sell T-shirt with the slogan “We make computers sing”. It took me awhile before all of Daisy landed in my head. But now I’m a big fan of this little micro processor.
I build a few of these. When I was working with a Windows machine I could just use one of them. On a Mac I can use all of them. They are for intergration of de DAW with my rack. But since I bought a ES-9 I hardly use them anymore.
Oh boy oh boy. This one is very special to me. I was in a bad period in my life when I started reading the Noise Generator Cookbook by Thomas Henry. Reading it gave me a lot of rest and I learned a lot from it. I didn’t know that much about noise, white, pink, red, blue and the noise in my head, it all started clearing up. In this book Thomas Henry writes about the Mega Percussion Synth (MPS). Back in those days a lot of schematics where based upon 15volt. I always wanted to have a MPS but never found the time and skill to transfer his design to eurorack (12 volts)
Then Haraldswerk released the MPS, and put the gerbers online for building one. Sadly it was still 15 volts and with banana jack. Not typical for eurorack. I wrote about this in the topic Haraldswerk posted on modwiggler. And I wasn’t the only one hoping for a 12 volt version with 3,5 jacks. That started a discussion and.. well
I found a way to remove all those post about the modules in my rack from the frontpage. I think I have most of them written now. I might need to update a few of them while playing with the modules more and more. I thought the frontpage got a bit messy with all those post so glad to found a way of removing them. Next up all the panel files I made and adding them to the website. After that maybe record some sound samples. Maintaining a website does take some time but I still enjoy doing it.
I just finished building the VCO and did a little bit of testing on it. I might update this post when I have used it a bit more. But first impressions it sounds really good. I like the FM and pulse input and have been playing with those CV inputs and lfo’s a bit and can imagine I would use this in some patches.
I have a love and hate relation with Erica Synths DIY modules. Some are quite nice to build but most of them are just terrible to build. I makes me wonder why Erica has left the DIY scene. I’m glad the put the designs on GitHub for the modules that they call legacy DIY. But I think the support desk was just overloaded cause these modules are just a pain in the butt to solder and are prone to make mistakes on. I had the VCO in my drawers for awhile and it was time to build it.