So, it was Knobcon 2016 at the hotel lobby bar. Ken Flux Pierce and I are prepping for the live streaming BeatPPL Pop-Up Podcast which was scheduled to happen the next morning. We both had our macbook pros out, open and running. Well, Ken Flux Pierce seemed to be having some issues connecting to the internet. The extent of my help went something like… “I’m on!”

Then there was a guy at the end of the bar. He may have said something like, “Yo, I used to work for Apple. I can fix that shit!” Maybe not exactly, but that’s what it all boiled down to.

Interestingly enough, the guy fixed it. Ken was able to get onto the internet and we were able to test his laptop for podcasting and live streaming.

So, who was “the guy”? His name is Tenkai. After he’d given Ken’s laptop life, we all chopped it up over drinks for over an hour. Tenkai went on to tell us all about his new module, the Fluxus One. We even got a chance to check out the Zetaohm Fluxus One prototype the next day at Tenkai’s booth. The look alone blew us away but the planned functionality was even better. Not to mention, it was a working prototype. We knew this was one to watch.

Since then, Tenkai and the Zetaohm team has been hard at work making the Fluxus One one of the most anticipated modules in the eurorack world. Within 24 hours of Zetaohm Fluxus One Kick Starter campaign going live it was 50% funded. Within a week the Zetaohm Fluxus One Kick Starter campaign was fully funded.

The long and short of it? I think this is someone you should know. So, allow me to introduce you to Tenkai of Zetaohm.

TenkaiSarahFor those of us that don’t know, tell us a bit about Tenkai.

Hey Corry, I am an artist originally from Brooklyn, NY. I plonked around Philly for a bit, then somehow wound up in San Francisco, working for Apple Product Design as a Systems Engineer. I learned a lot about design philosophy from working with engineers there. When I was a kid I was obsessed with Propellerhead Reason. The patch cable view was amazing, and opened up a whole new world for me. When I went to college, I became very interested in guitar pedals. Building DIY clones of old pedals like the Tychobrahe Octavia (Hendrix’s main fuzz) was something I really enjoyed. I wonder what happened to those…

So, your company Zetaohm is a relatively new player in the modular game. How did Zetaohm, the modular company, come into existence?

While working at Apple, I got into the Modular synths. I got a Macbeth X-Seriies Micromac. It blew my mind. I discovered sonic realms that I had never reached before. I dove deep. Music, in my mind, is quite melodic. I needed a sequencer, so I began to work on what would be come Fluxus One. Zetaohm is the company that was formed around the concept of Fluxus One.

Is Zetaohm a family owned / run company? Who is on the team?

Yes, Zetaohm is currently comprised of Sarah (my wife) who helps with business administration, logistics and motivation Maro (my brother) who is currently helping with testing, feature planning and demos, and myself. I do all the engineering, programming, design work, prototyping and DFM.


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As a modular synthesist, what are a couple of your favorite modules to make music with at the moment (besides your own Fluxus One)?

Definitely the Macbeth Micromac. It is amazing. It has such a massive sound, and can be wrangled to do so many things. The Atlantis is my go to Acid sound (although I am looking for an M303 right now..). It is quite versatile for a single oscillator voice. I really love the sound of the Schippman CS-8 multimode filter, but I can’t find one these days!

Now, more about Fluxus One…

Your first module, the Fluxus One Voltage Sequencer, is a monster of a project and a very unique module in functionality and appearance. I’m happy to see it come along so well. What was the inspiration for this module?

The idea for the Fluxus One began probably about 5 years ago. I was making all my sequences for my modular in Ableton. Ableton has one of the most powerful sequencers out there, but it was limited in the sense that it still goes through MIDI to CV conversion. Even so, there were some key features that really made sequences more interesting. Things like randomization (with a range) before a quantizer, beat repeat functions, and of course, an arpeggiator. Feeding chords into ableton and getting out arps was a go-to function for me. I wanted to encapsulate that in hardware. I was able to accomplish some of these things with the Elektron Machinedrum back in the day, but that was still MIDI, and also very limited in its performance capabilities. The Machinedrum workflow heavily inspired the Fluxus One workflow.

The concept behind Fluxus One, as it has evolved, is a compositional device. A module which allows you to bring a musical idea that exists within your mind, program it into the module, and express it as voltage levels over time. The key part here being “voltage levels over time”. There are many ways this can be interpreted, and any implementation will have constraints that bind its capabilities. I chose to attempt and push those capabilities to the limit of the micro controller which I chose.

One of the first decisions I made was to give Fluxus One a full 20v (±10v) analog output swing on gain stage after a 16 bit DAC, allowing you to access states in analog modules which may otherwise not be accessible, while giving you the resolution you need. I determined this was essential after analyzing one of the most popular modules: Make Noise Maths. This is arguably one of the most ubiquitous Eurorack modules, and I think the snowball effect has given it some of its popularity, but it really does give you some crazy sounds when you hook it up to an analog voice. I think it is because you can actually squeeze higher than rail to rail voltage out of that thing! I am not exactly sure how, but I was able to get a waveform that went all the way down to -14v on a ±12v rail. Connect that to the filter cutoff of an analog module designed for ±5v or ±10v and you are searing beyond the design specifications. Happy accidents are some of the best moments in modular synthesis, and breaching the ‘intended usage’ of module designers is a great way to get there.


Zetaohm’s Fluxus One

The second major decision I made was to have a switched, digitally controlled, analog glide circuit based on the glide of the Roland TB-303. It is a very simple circuit, just a capacitor to ground in series with a resistor, but instead of a regular resistor, I use a rheostat (digital potentiometer). By sending the rheostat different signals, I can control the resistance of the rheostat, and go one step further than a 303 glide, and actually control the amount of time it takes for the glide to complete. This gives you the ability to have just a little bit of softness on a note, all the way to a whole 3 or 4 seconds to a step to stabilize on its target voltage. Think Kraftwerk: Metropolis. Thats what I was thinking about. This circuit is also switched, so when glide is turned off, its is completely disconnected. Rheostats are great, but the zero scale resistance is about 70 ohms. In order to achieve variable glide in tandem with extremely sharp pitch changes when you don’t want any glide, you had to be able to completely disconnect the circuit. One really great thing about the glide circuit is that it allows Fluxus One to create a perfect sine wave LFO, despite being digitally generated.

Most times I’ve seen VCOs and Filters as a company’s first module. You have definitely chosen to attack with the big guns fresh out of the gate. What made you choose to tackle a sequencer as module first?

It is the module I wanted. I made the Fluxus One for myself, primarily. It is why I have made no compromises. My brain has an aptitude for analyzing and understanding networks. I can see how things connect to each other. For me, the sequencer was just figuring out how to get different components to talk to each other at the right speeds and levels. Once I got that out of the way, it was merely a question of refinement. I had a vision, and that vision has changed a little here and there as I learned more about what I needed to do to realize it, and what was possible, and what wasn’t, but the core of that vision was unchanged.

How long has the Zetaohm Fluxus One been in development?

The idea was germinating and began conceptualizing about 5 years ago. I began prototyping about 3 years ago, and I started working on this project full time about a year and a half ago. This project took more than a few thousand hours to complete.

What advice would you give to aspiring makers out there who may have ideas that they want to bring to market some day?

Do something for yourself. Do something that will make you happy, even if nobody likes it, because at first, nobody will. You have to suck for a long time before you are any good, so get real good at sucking, and then one day, you will look back at what you have done, and realize you suck less than you did when you started. Then do it all over again. Iterate as many times as you can, but make sure you are learning something in each iteration. See your failures as steps on a ladder, because they really are opportunities to bring you higher.

Congrats on reaching full funding on Kick Starter and for being a kick starter favorite. Whats the journey look like from here with the Fluxus One? Also, when do you think you’ll make it to market and fulfill the kick starter backing orders?

Thank you! Well right now I am working on the finishing touches before I send board files to WMD to do the first run. I am also working on software so I can have the minimum set of features that are necessary to ship. We plan to have them out the door by the end of June, but if everything goes smoothly, it should be sooner than that. I just got the buttons in from my manufacturer and they look AMAZING, and on the first try. I was a bit worried about that, but it all worked out. Reguardless, we are on track to meet our Kickstarter promise of delivery by July 2017.

For Fluxus One, though the journey is just beginning. I need this to be in the hands of other capable musicians who can put it through its paces, and who can see what works and what doesn’t work for them. Fluxus will be a part of many new musical journeys and I am sad that I won’t be there for most of them, but its also kind of magical that I will have played a small part in so many compositions.

And for the next act… What’s planned for a follow up? What can we expect next from Zetaohm?

Ahhhh, I have so many things I am working on, but after this massive enterprise I’d like to work on a smaller project next. Keep an eye out for a new kind of drum module. I want to take some of the lessons I have learned with Fluxus One and apply them in different scenarios. Superbooth17 was motivating and inspiring for many reasons, including some deep conversations I had with Ken Macbeth. He challenged me to come out with 4 new modules by next year, and I intend to meet his challenge. He gave me some great tips, including directions on where to look for the master sword…


Keep up with Tenkai, Zetaohm and the Fluxus One below

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