Tuesday 20 August 2019

Sloth DK

6HP Sloth DK


For those that have not seen the Sloth before - this module is a simple chaos circuit that puts out 3 slowly varying and never repeating CV signals. It is not random as the chaos occurs within a bounded region and generally moves in or between two strange attractors or wells.

It is really slow and can take from 8-20 hours to complete a chaotic orbit.
Generally the output signals range between +/-4V, tho mostly around +/-2V.
The middle output is simply a mix of the two main outs, passing through the pot to attenuate the signal if you wish (and it helps hold the PCB to the panel). It is a little hotter and more complex that the individual outs.

There are no inputs and no way to control it.

The large capacitors sticking through the panel never see more than +/-0.15V in normal use. Nevertheless you probably should not take the module out of the case and rest your tongue across their leads.

PCB = USD12
Panel = USD20
assembled = USD100 

Build guide on wiki





flamingo situation.......

1U Signum

In the simplest sense, this is a switching module. It is a little different though because it has 3 states rather than just on/off:

In this case, the module uses approx 1V, rather than 0V, as the switching point, so that it can be controlled by gates. It is simple to bring it back to 0V for those who think it should be.
Also the '0' state is really a result of the diode voltage drops rather than any circuit design trickery.

The signal on the bottom input is fed to the switch of the Switch jack (oh yes) so the incoming signal can switch itself without any help.
The three states actually mean there is a flat spot at the switching point, so the circuit can be used for audio but at slow rates there is a click, so it is far better suited for CV processing.

This circuit originally was used as the nonlinear element in the Primal Hyperchaos and two of them in the Hyperchaos Deluxe. I quite like it on its own, so the Signum Hyperchaos brought the signum section to the panel where it could be used as a stand-alone module. This version drops the chaos and just has the Signum.
The switching is done by diodes rather than a dedicated IC.

The panels are available in white/gold and black/gold in both Pulp Logic and Intellijel formats. Please specify which colour and which format you want when ordering.

Also the PCBs are the same for both panel formats and use a standard Eurorack power connector. There is no provision for the Pulp Logic 3 pin power connector.

PCB and panel set = USD10
Assembled = USD55

Build Guide on wiki









VCAs

This 8HP module contains 3 VCAs and a fuzz/distortion. The VCAs are similar to the ones used in the NLC Cluster; simple OTA based but work very well.

The fuzz/distortion is part of the bottom VCA and is a typical diode based affair, on the PCB the space for these are thru-hole so you can install Si or Ge diodes or LEDs. Turn the Fuzz pot to 0 if you just want VCA.

PCB = USD18
Panel = USD20
assembled = USD160

Build guide on NLC wiki





Beat Freq

The idea for this module came from a schematic that has been floating around the web for years - 'beat frequency indicator'
The idea is to feed the circuit two signals and depending upon which one had the higher frequency the ring of 4 LEDs would light up in a clockwise or anti-clockwise direction. The speed of rotation would indicate how close or disparate the frequencies are. If the signals have the same frequency then just one LED is lit.

The original circuit used 74xxx series ICs for the logic, so it was simple enough to find the CMOS equivalents (sort of), then add gates corresponding to the LEDs and use the spare outputs of one chip to feed pots to make sequences. Then for good measure a discrete XNOR circuit was added to give a pseudo ring-modulator output based on the 2 incoming signals.

In operation this module is quite unique; the CV signals return to 0 between each step, the length of each step can vary depending on the incoming signals. Gates come in spurts. The circular LED display jerks around, sometimes it completes several revolutions confidently and then stutters between two stages, sometimes it shimmers on one spot.

At both audio rates and clock rates, this module is quite unpredictable but always seems to be putting out useful signals.

PCB = USD18
Panel = USD20
assembled = USD160

Build guide on NLC wiki




This video is from the 1st version proto-type, tho little was changed in the production version -




Monday 12 August 2019

1U 6HP Difference Rectifier

Those that build a lot of NLC modules will know this is one of my favorite circuits. The diff-rect has appeared on the Neuron, 1050 mix/sequencer, triple Sloth, GENiE and 8 of them make up the Let's Splosh.
It is great for mixing audio and/or CV signals to get all kinds of unexpected and interesting results. This page from 2012 on my old Pinky site has some more details.

The panels are available in Pulp and Intellijel formats and in white/gold or black/gold, please specify when ordering.
  Please note, the PCBs only have eurorack 10 pin power connectors, not the Pulp Logic 3 pin type.

PCB & panel set = USD10
assembled = USD55


Build guide on wiki