• New Site! New Knot!

    Hello from my new website! It's restyled for the 20s with some gradients and a new logo... Sorry if you checked the site between 1PM and 3PM EST on 05/13/22. I was having an issue with Jekyll that turned out to be caused by the fact that I was using keywords for my layouts "Page", "Post"and "Home". Dont use these words, they apparently break Jekyll...

    Check out this beautiful render depicting the new Double Knot v3 by Max ! There's more where that came from, too. Happy to say that the Double Knot circuit boards are now being assembled here in Maryland and the new aluminum cases are manufactured nearby in Pennsylvania. Pre-orders available in my web store while supplies last.

  • Happy New Year! long time blog silence

    I've added a mailing list sign-up form to the bottom of the home page. I'm going to try it out as a way to send updates besides Instagram. Subscribe if you like!

  • With Hidden Noise

    I learned about this Marcel Duchamp piece With Hidden Noise at art school. It's a ball of twine with some unknown objects inside, clamped on top and bottom with brass plates and four bolts. It's an art rattle with unknown objects inside... Mystery objects contained and some sound as a clue. Supposedly Duchamp never knew what the objects inside the ball of twine were. They were chosen by a patron. Also, I think it has a very nice form like a four legged animal, or a funny building on stilts... it has some life of its own.

    The chips and components themselves as small versions of this piece. Hidden noises encased. Epoxy potted invisible structures that give characteristic sounds to indicate their inner-workings.

    I made my own art rattles out of HDPE scraps and dead components. The components are in this case not used for their electronic potentials but for their material properties as the filling for the rattle. -Will

  • Memory Devices

    I've begun to interface more with microcontrollers technically, philosophically. Learning about them as hardware and writing assembly for PIC controllers from the Microchip brand. Some already, and more to come, I'm dipping toes into the ST brand too.

    The questions I keep asking myself are, What is it to work with microcontroller devices as material? What are they good for?

    • Small computer
    • Memory
    • Use of modern protocols, USB, SPI, I2S...
    • Defferent type of precision, unknown to analog circuits
    • Adaptible, Reprogrammable
    • Low energy?

    Silicon die images taken from PIC Microcontrollers Wikipedia, added stone and wood floor patterns in Gimp

    Because the approach has been from considering them as hardware first! I've started thinking of them as little "memory devices". All they do is act on memory. There are logic operations, arithmetic operations, peripherals and so on, but all of these functions are acting on, or drawing from memory. One clock at a time, taking something from one location, storing it in short term memory. Taking something from another location. Add the contents of these two register locations. Store the result back in the first memory location. The memory map! Long-term, short-term, program... all of the settings for each port, each pin, are part the memory map. Devices for sale are categorized in tiers of how much memory they have for different tasks. In the CMOS Cookbook Don has a section heading "What Is A Memory?" It is noted here that latches and flip-flops can be a kind of volatile memory. We can use latches in logic circuits for short term memory of one bit, byte, or a few bytes. We can use shift registers to make a river of bits that flows on the clock's time base.

    Analog hardware has the "program memory" in its very construction. Or I guess in analog memory hardware, a diode rom or something, core rope memory... Short-term memory can be realized in a flip-flop or as a charge stored on a capacitor. When everything is seen from the vantage point of memory hardware and memory manipulation, microcontrollers can open up the spatial and hardware brain. Imagining the invisible memory locations of the micro devices and trying to navigate them as someone might, rooms in a building.

    -Will
  • Knas World HQ

    I went to Karl's shop for a visit to see what he's been working on. If you're wondering how I got there from Charles Village, I went St Paul to 40 Like I'm going to H-mart but I turned on Pulaski. On the way back I took 40 -> Paca -> Howard.

    Karl showed me around his warehouse workspace and we talked about different projects and aspects of precision and efficiency. Mostly machine talk, although he showed me a prototype of a many-stringed electro-acoustic instrument he's been working on. In the pic below there is a molded plastic part made from recycled detergent bottles that factors into the electro-acoustic piece. In the top right there is a prototype board framed, and top left is a view looking west from the fire escape.

    The cnc router that he's built is very impressive, a large work area and built of extrusions, steel bars, motors, and a base of unistrut!! This machine does the work of cutting aluminum enclosures for his signature product "The Moisturizer" as well a bunch of other things... Furniture for his workspace, aluminum and steel parts for various machine endeavors. The green is cool.

    Another gantry type, the pick and place machine. This thing does the work of putting the small SMD parts on circuit boards to then be baked in the oven for soldering. Cameras look with computer vision to account for misalignments in the picking and the placing actions. Cool!

    The Moisturizers await some knobs. Karl has been making this device for nearly a decade, classic!

    Plastic recycling: We talked a good bit about remolding plastic parts. This is his plastic shredder machine (in the upper left hand corner) and his injection machine... All the steel parts for the shredder were cut on the router. Very impressive! I have some interest in these processes.

    Thanks for having me Karl. Always great to check in with other synthesizer builders and see what's going on!

    -Will
  • Year End
    Burdock Pickles

    Recently made a big batch of burdock pickles with Lucas, I took pics for this recipe photoset.

    1: Peel all the burdocks and cut them up into "matchsticks"

    2: Boil with slices of ginger for about 15 minutes

    3: Remove the boiled burdock with large spoon with holes

    This liquid left from boiling the ginger and burdock is tasty tea, I put a little bit of sugar in it.

    4: Soy sauce, rice vinegar, rice wine, honey, dried chillys, sliced garlic, and sesame seeds.. all to taste.

    I'd say pretty well cover the burdock roots and favor the rice vinegar, maybe add a bit of water. I think in this bowl the mix was something like two tablespoon soy sauce, 1/2 cup rice vinegar, 1/4 cup rice wine, 4 chillies, 1 tablespoon honey, 1/4 cup water...

    Keep them in the fridge and they stay good for about a week



    CNC update/ e-waste finds

    Let me brag about my good fortune. There was a box of "scrap aluminum" at the makers pace where I work sometimes, Mike C said it was all up for grabs. It was left behind by the high school robotics team that had been working in the space. I rooted around in the box to find a bunch of custom machined aluminum parts and motors and things. I was expecting to see some bent up extrusions and burnt up hobby motors. Instead, industrial automation motors and precision machined parts stamped with revision numbers and all tumbled or sandblasted... The parts were strange, and no doubt very expensive. Probably, they had been donated to the team by a company that couldn't waste time re-purposing these motors and recycling the custom parts. I went through the box, plucking parts to keep. Still not sure what I will do with some of the parts yet, but one of the parts that I found, I have put to use. I found a new Z axis for my small CNC at home. It happened to fit the same size motor that is already on the machine and be about the right amount of travel. In updating the axis I didn't want to put the trim router back on the machine as it seemed too large for this new slim and smart z axis. I changed the spindle to an ebay-belt-drive type. Still waiting on the DC motor drive module so I can be interfacing the spindle with the router's computer.


  • More on simple envelopers

    I haven't seen Mike in a while, I wonder if he is still in Baltimore. He plays one of Karl's big synthesizers called The Polygamist and as far as I know that is his instrument. We had a conversation about envelopes one time when I bumped into him at Ace hardware. He was calling the circuits that generate envelopes -- envelopers. I really like the term, I guess it's Envelope generator contracted... enveloper. Or its about envelop? like enveloping. Either way, or both ways, I think it is good.

    I've got some more stuff here about simple envelopers, a re-look at the one in the double knot and the one from the previous post I wrote about simple envelopers. Not a whole lot essentially different about this design but the watercolor below includes an AND gate at the input which (while it was in the Double Knot) was not included in the schematic from the previous post.

    This AND gate setup works best for some system like the double knot where there is a clock and a stream of on bits ( like from a shift register) that you want to chop up with the clock... getting individual pulses. If the AND gate is not desired, your system is not about clock and confluence. Consider this alteration below where in one switch position, both inputs are connected to same signal so as to always trip the envelope on the rising edge. The other switch position then would be a gated looping function where when the input is held high the enveloper loops.

    Not much else to it really, just a darling little pair of transistors making the voltage spike instead of a comparator, so freeing up second op-amp to loop the thing. Same current sink as before, this is a staple. This circ in the looping mode is very much the opposite of the common integrator and short rampwave oscillator. This works in the fill, drain-over-time, detect-level-with-comparator-which-then-fills kind of way.

    Alteration

    You can set the red comparator to loop the envelope at any voltage above the output swing of the amp (with a 9v supply and a TL072 this is something like 1-8V) or a variable voltage... ;^)


    Another thing to do may be to amp the output with a non-inverting topology. I found that with the 9V supply I was getting a 0-5V envelope. I wanted to maximize the output so I put a 223 resistor feeding back to the - input and a 103 pulling to the mid reference of 4.5V...

    I think that's all I have for now.

  • Construction Techniques : Bulding circuits with linoleum cutter and magnet wire

    -- a prototype technique idea here -- Like everyone I mostly use a breadboard, but recently in the mood to be soldering and really building an object with some life beyond the temporary. I will just note here The artworks, cartoons, and engineering of Jim Williams as an overall inspiration, but especially for these construction techniques. So I use an art printing block cutter to cut board traces sometimes. The kind with plastic handle and replaceable blades for linoleum. Using this technique I'm cutting with much more ease than cutting with a utility knife. I use the deep sturdy v cutting blade to remove a good width of copper so to be sure I wont easily bridge the planes. I mostly use FR1 (paper and phenolic resin with copper on one side) from the internet rather than FR4 fiberglass for the sake of keeping the blades sharper longer, its easier to cut, and its also less toxic. Also I sometimes end up making panel for and out of the proto circuit by just drilling and mounting pots with the nut and then soldering to the legs. A single plane with all of the components and dials and plugs floating on and through it as the panel and circuit plane. Bananas can be the 5mm brass grommets which fit the 4mm banana plugs well! overall I have been enjoying this as an easy proto/quick fab technique. allows a non linear work-flow like -- cut some traces then solder some components then cut some more and try something else... its more freeing to me than breadboard also I can tell better what is and isnt connected! it can be hard to track down bad breadboard slots. I use mostly magnet wire to jump, of a gauge like 30 -- easy to tin with just the soldering iron and it just goes on there solder it up. There is an enamel coating which covers the wire and it is easily removed by just tinning the end of the wire. It also makes it easier to remove the coating in the middle of the wire without stripping it or cutting it. This way of using magnet wire comes from Elm Chan. These pictures should be instructive. I like the way this technique allows me to wander and think as I work. More thoughts and developments to come soon, hopefully some on the HDPE recycling/injection molder idea.

  • Plastic Thoughts

    I have been working with thermoplastic smithing in parallel with producing double knots... As I cut the cases for the synthesizers from sheets of HDPE I am thinking about working with this material and what it means. The more I think about it, cutting the stuff is like pushing a ssslllooowwwlllyyy moving liquid (especially in the heat of summer) endlessly mutable for sure. Having studied sculpture in school some professors learned us to "read materials" as signs in themselves, the medium IS the message. Infinite mutability of material form and soundsynthesis. Anyway, I got the idea that I would save some chips from the sheet cutting process to be recycled later into other forms, not sure yet what forms but I started saving. I then got married to the idea of an injection molder to experiment with the authority of one of the most prevalent manufacturing techniques and to see if I could know what it's all about... I did a lot of research online and found some different ideas about manual press injection molders, melting temps for the stuff, and safety info about working plastics. I surfed mcmaster to get my aluminum tube and plunger material and went to eBay for 1.5" band heaters, got a closed loop heating controller from amazon and so built a heated aluminum tube syringe. Pictured below after having tested the heating controller and plunged some small logs from the syringe with a temporary copper loop to retain the two pieces. I needed some way to administer force to the plunger so I gripped from harbor freight in exchange for legal tender a 1ton arbor press and tapped a hole in the end of the rack gear for to the plunger to thread. While I was in the harbor freight I also bought a plastic dead-blow hammer. Two-by-Fours (one-and-a-half-by-threes) with glue and carriage bolts will make a stand for the press. A scrappy machine is taking form for testing the idea of reconfiguring plastic waste material from cutting high density polyethylene. Essentially the CNC machine, as its cutting the plastic, has the double duty of being a plastic shredder! The investigation of this complementary additive process to the initial subtractive process may turn to be a quagmire but I will have to find out ! I am too curious about this process which churns endless plastic tchotchkes and lawn chairs.


    Will

  • PMF & CNC

    I held a table at Publications and Multiples Fair VIII in Baltimore April 1st & 2nd. What a time! The PMF is a thoroughly galvanizing event put on by Open Space Baltimore which brings artists of all kinds from all across the USA to sling their wares, to shop, and to trade in the PMF arena. This is a very special event which reminds me of the uniqueness of Baltimore's arts and music realm as well as announces the season of spring. Pictured below is a view from my table. I was next to Jimmy and Stuart. At my table I had for sale the Double Knot synth as well as a special kit I made for the PMF event, bearing the same initials, The Petit Mini Filter. The PMF is made up of a input preamp stage, a transistor ladder lowpass filter, a wavefolder after the filter, and a simple relaxation oscillator. The kits were a success, I dont have any more. For download and printing here is the build doc and some schematics. Edit: Now in April 2020 this doc has been superseded. Here is the updated version of the design please build this! if you need the original doc for any reason please contact me by email. Below is a pic of my display... I brought the scope to help attract the image and screen inclined. And some snacks because PMF is quite a marathon. I engraved some PCBs for the PMF kits on my CNC machine and after cutting the boards for the Fair and feeling the jolt of spring, I made some upgrades to my machine. I added two T-slot extrusions that will hopefully make the machine more rigid and provide a long term flexible hold-down system... I bought the tslot tables from Misumi, item number HFSQN4-15250 (if you google this number you'll see some other cnc diyers have pointed out this part as well...) and some 8mm nuts which slide in the t-slots. I got 1/4in by 2in by 24in pieces of aluminum from mcmaster to make adapter plates which will screw into the front and back steel angles of the cnc frame and couple to the 6mm tslots on the bottom of the extrusion. I put the nut and bolt on there like this then slid the t-slot extrusion onto the rear nuts and bolts... Then I did this on the other side where I held the nut in the tslot with an allen key and screwed in the phillips with one finger... happy spring