Collaborative Guest Post: Naomi Mitchell of Omiindustriies and Kris talk shift registers and the new Omiindustriies DDSR
This is part of a series of guest-post tutorials where friends of Noise Engineering show off various tips for NE modules, modular use in general, or how they integrate modular into their workflow.
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For this installment of the NE blog, we’re pleased to introduce Naomi Mitchell from omiindustriies. Naomi came by NE Headquarters (also known as our living room) and we chatted a bit and she showed off the new module, which is a shift register.
Kris: Hi Naomi! Welcome back to NE. First, please tell us a bit about yourself and your company.
Naomi Mitchell: I am a Los Angeles-based artist, musician, and eurorack synthesizer builder. My company is called omiindustriies, not omni industries as many people have mistakenly called it. I also perform under the name omiindustriies. We’re releasing our first module, the Dual Digital Shift Register, a shift-register based pseudo-random voltage and gate generator, soon.
KK: Cool! How did you get into modular?
NM: I got into modular through my interest in circuit bending and lo-fi DIY noise boxes. From there I started seeing a bit of eurorack gear but I really got bitten by the modular bug when I saw Surachai's demo of the Make Noise Phonogene. As soon as I saw it, I was just like "I need that." It was actually the first module I ever bought and for a while all I had in my rack was that and a Make Noise Wogglebug which is a really fun combination. Endless hours of sample manipulation. After a while I realized that there were things that I wanted in my rack that didn't exist in the modular marketplace and so I started thinking about all the things I wanted in my system. That’s when I started designing the DDSR.
I love the modular community. There's not really competition between manufacturers in the same way there is in a lot of other fields. Everyone is working together for a common goal. Also for the most part the modular synth community has been really accepting. As a transgender woman, I was nervous about rejection in the community but everyone has been really nice and supportive.
KK: What’s next for omiindustriies?
NM: We have several modules in development, including a sequencer that uses gate signals to generate patterns called the Gay Did Seq, an unnamed as of yet attenuverter and cv mixer, the Omiidrum a granular drum and complex random module, and the Quad Logic, a four-channel logic module. Also, our friend Echo is going to be helping code some of our upcoming modules is also going to be porting over our modules to VCV rack.
KK: Awesome! Let’s take a closer look at the first module from Omiindustriies, the Dual Digital Shift Register, how it works, and how it works with other modules. First, the basics on how a feedback shift register works.
Anatomy of a feedback shift register
A typical shift register has two inputs: a clock input and a data input which expect binary (on/off) signals, i.e., gates or square waves. When the clock goes high, the shift register looks at the data input; if it is also high it puts a high signal into the first stage of the shift register. If it is low, the first stage is low. On the next clock pulse, the shift register moves the value from the first stage down to the second (and so on), and then populates the now-empty first stage with a high or low value based on these rules. When a bit reaches the final stage, it is fed back into the data input and is xor'd (at least in the most common application, and for our purposes today) with the incoming data signal: if either one of the inputs are high, the stored data signal is high. If both of the inputs are high, the stored signal is low.
The Dual Digital Shift Register is a cmos-based shift register designed to generate chaotic cvs and gates. It also incorporates a comparator circuit, so you don’t have to use a gate signal---you can use any signal over 0.5 volts. The outputs are determined by the relationship between the clock and data inputs: closely related inputs, like a clock generator with even divisors, will make a loop pattern. More irregular inputs, like odd divisors, sources other than master clocks, or two unrelated sources, will create more chaotic patterns. Each stage has a gate out (for 4 gate outs per side) with LEDs that indicate whether each stage is high or low. CV generation is done with two 4-bit shift registers and a digital-to-analog converter (DAC) to create pseudo-random voltages. The DAC uses the inverse of the stored bits to create the cv output, so all bits at 0 outputs the highest voltage, and all bits at 1 means the lowest voltage.The DDSR outputs a bipolar out from -5 volts to +5 volts.
Using the DDSR
The DDSR is fun with CVable clock dividers -- I modulate the clocks with the DDSR itself. Examples include the Make Noise Tempi, 4MS rotating clock divider, or the Noise Engineering Horologic Solum. Patch the cv output of the DDSR into a cv in on the signal for the clock or data oscillator to make a feedback loop. Use an attenuator to dial in the amount of feedback introduced in the patch.
Here’s a big patch using the DDSR that Naomi threw together using the NE demo case and a skiff she brought along.
A few key elements of the patch include the Noise Engineering Horologic Solum as a master clock for the Numeric and Zularic Repetitors. Those feed the Confundo Funkitus. These feed one clock for the DDSR. Horologic Solum also sends a clock to the Make Noise Tempi, which provides a clock for the other side of the DDSR.
The Make Noise Phonogene is playing a prerecorded sample, but is being modulated by the DDSR. CV from both sections of the DDSR are being used to modulate gene size and organize and slide is modulated by a gate.
There are three BIAs in the patch, and DDSR CV outs are also going to decay on one and attack on the other. She is also sending gate outs to modulate various parameters, including BIA and Manis Iteritas parameters, and Numeric and Zularic Repetitor parameters to change the patterns.
For more information on omiindustriies, check out
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